JP2003235343A - Method for producing porous granular body having raw material inorganic waste - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing with a technique with small environmental loading a porous granular body having the quality of a gardening material, a construction material, a soil improvement material, or the like. <P>SOLUTION: This method for producing the porous granular body comprises using as the raw material inorganic waste such as molding sand dust, crushed stone sludge, construction sludge, water supply sludge and coal ash, adding a lime raw material and water thereto, producing a kneaded product of a funicular I and II state to a capillary state by medium speed kneading, and forming the product by vibration if necessary and subjecting the product to a hydrothermal treatment, and further to a crushing treatment and a classification treatment if necessary. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a powdery or muddy waste material containing a large amount of silica (SiO ₂ ) such as foundry sand dust, crushed stone sludge, construction sludge, tap water sludge, coal ash, etc. which have not been effectively utilized. As a raw material, the lime source material and water are added, and the kneaded material in the funicular I, II state to the capillary state produced by medium-speed kneading is subjected to vibration molding, if necessary, and hydrothermal treatment is performed, and further The present invention relates to a method for producing a porous granular material that can be used as a horticultural material, a soil improving material, a civil engineering material, etc. by performing a crushing treatment and a classification treatment according to the above.

[0002]

2. Description of the Related Art For example, in Japanese Unexamined Patent Publication (Kokai) No. 6-93260, blast furnace slag, potassium compound, etc. are added to inorganic waste (waste foundry sand), and after granulation, firing is performed at 850 to 1300 ° C. Describes a technique for producing a soil conditioner having a fertilizer effect. In this technique, since the firing process is performed at a high temperature, a large amount of energy is used and the environmental load is large. As for the quality of the granular material, the pH of the eluate is near neutral, but the water absorption rate and cation exchange capacity are small. Furthermore, the color of the granules depends on the composition of the inorganic waste, gray, brown,
There are various colors such as black.

Further, in Japanese Patent Laid-Open Nos. 2001-121196 and 2001-122647, a calcium compound is added to inorganic waste (mud sludge), and
Aggregate that can be used for concrete fine aggregate, roadbed material, horticultural material, etc. by granulating by high speed stirring of 00-800 rpm (Flude number is 2.5 or more) and then hydrothermal treatment at 130-300 ° C. A method of manufacturing is described.
This method is agitation granulation at a high speed, and produces a dense substantially spherical body with a small amount of water. Therefore, the progress of the hydrothermal reaction becomes insufficient, the water absorption rate is as small as 25% or less, the strength of the aggregate is low, and the unreacted CaO remains, so that the eluate has a high pH. Further, the color of the granular material varies depending on the composition of the inorganic waste and the like, such as gray, brown, and black.

Further, in JP-A-55-124599, a calcium component is added to inorganic waste (sludge),
After molding (pressurization, rolling, extrusion, etc.), 1 to 20 kg / cm ²
It describes a method for producing an aggregate that can be used for landfilling, etc. by performing hydrothermal treatment at (100 to 211 ° C.). In this technology, molding is a method of obtaining a cylindrical object and a spherical object by pressing, rolling, high-pressure extrusion, etc.
The state of the kneaded material is considered to be the funicular I state, and the molding is performed by a method different from the vibration molding in which no pressure is applied. Therefore, as an aggregate characteristic, the particle size is large,
The particle size width is small, the water absorption rate is small, the strength of the aggregate is low, and the pH of the eluate becomes high due to the residual unreacted CaO. Furthermore, the color of the aggregate varies depending on the composition of the inorganic waste and the like, such as gray, brown, and black. From the above,
With the conventional technology, it is difficult to manufacture a porous granular material having a color according to the application by a technology having a low environmental load.

[0005]

As described above, in the technology for producing a safe and highly useful porous granular material using inorganic waste as a raw material, the treatment temperature does not become too high, and the amount of energy is small. It is desired to develop a technology with a low environmental load capable of producing granular materials. Further, in the above-mentioned granular material manufactured by the conventional technique, there are problems in water absorption rate, cation exchange capacity, and eluate pH, which are properties required when used as a gardening material, and satisfy the quality as a gardening material. It is desired to develop a technique capable of producing a granular body, that is, a granular body having a high water absorption rate, a high cation exchange capacity, and a low eluent pH.

Further, the above-mentioned granular material produced by the conventional technique has problems in particle size distribution, compaction characteristics and strength, which are characteristics required when used as soil wood, and satisfies the quality as soil wood. It is desired to develop a technique capable of producing granules, that is, granules having a wide particle size distribution, excellent compaction characteristics, and high strength. Further, as described above, in the prior art, the color of the granular material was varied depending on the waste composition and the like, but a porous granular material having a color according to the application is not affected by the composition and color of the waste material. Development of manufacturing technology is desired. Furthermore, in terms of safety, it is necessary that the eluate satisfy the soil environmental standards.

The present invention has been made in view of the above points, and an object of the present invention is to provide a lime source material for inorganic waste such as foundry sand dust, crushed stone sludge, construction sludge, tap water sludge and coal ash. And water were added, and the Froude number was 0.1-2.
A kneaded product of 0, preferably 0.5 to 1.5, in a medium speed kneading, in a funicular I, II state to a capillary state is subjected to vibration molding, if necessary, and then subjected to hydrothermal treatment, and further, if necessary. An object of the present invention is to provide a method for producing a porous granular material having a water absorption rate of 30% or more, which can be used as a horticultural material, a soil improving material, a civil engineering material, etc. by performing a crushing treatment and a classification treatment.

[0008]

In order to achieve the above object, a method for producing a porous granular material using an inorganic waste as a raw material according to the present invention comprises 100 parts by weight of the inorganic waste and a lime source material. 2.5 to 25 parts by weight and, if necessary, water 0.01 to 3
Add 0 parts by weight and add to a kneader to obtain a Froude number of 0.1.
To 2.0, preferably 0.5 to 1.5, and kneading at a medium speed to obtain a substantially spherical granulated kneaded product in a funicular I state having a water content of 20% or more. 3 to 1
After classifying at 0 mm, crushing 3 to 10 mm or more after crushing, returning to the kneading machine or input material, and curing at 3 to 10 mm or less at room temperature to 95 ° C for 0.2 to 36 hours , 130 to 220 ° C. for 1 to 24 hours (see FIG. 1). In the above method, the granules obtained by the hydrothermal treatment may be classified to 0.1 to 1 mm, and those having a size of 0.1 to 1 mm or less may be returned to the kneader or the charging raw material (see FIG. 2).

The method of the present invention is also applied to the inorganic waste 10
To 25 parts by weight, 2.5 to 25 parts by weight of the lime source material and, if necessary, 0.01 to 60 parts by weight of water are added and charged into a kneader, and the Froude number is 0.1 to 2.0, preferably 0.5 ~
The mixture is kneaded at a medium speed to give a kneaded product having a water content of 30% or more in a funicular II state or a capillary state, and the kneaded product is aged at room temperature to 95 ° C for 0.2 to 36 hours. Then, a hydrothermal treatment is performed at 130 to 220 ° C. for 1 to 24 hours, and then a crushing treatment is performed (see FIG. 3).

In the method of the present invention, 2.5 to 25 parts by weight of the lime source material and 0.01 to 60 parts by weight of water are added to 100 parts by weight of the inorganic waste as a raw material and kneaded. It is charged into a machine and kneaded at a medium speed so that the Froude number is from 0.1 to 2.0, preferably from 0.5 to 1.5. After kneading and vibration-molding the kneading product, the mixture is kept at room temperature to 9
Curing at 5 ℃ for 0.2 ~ 36 hours, then 130 ~
The hydrothermal treatment is performed at 220 ° C. for 1 to 24 hours, and then the crushing treatment is performed (see FIG. 4).

In these cases, as pretreatment, 0.5 to 20 parts by weight of an oxidizing agent such as nitrate and 0.01 to 60 parts by weight of water are added to 100 parts by weight of inorganic waste and kneaded. The obtained kneaded product is 0.2 to 1 at room temperature to 220 ° C.
After the heat treatment or the hydrothermal treatment for 5 hours, one of the above treatments can be performed by adding a lime source material and water if necessary to the obtained treated product (see FIG. 5). To 100 parts by weight of inorganic waste, 2.5 to 25 parts by weight of lime source material, 0.5 to 20 parts by weight of an oxidizing agent such as nitrate, and 0.01 to 60 parts by weight of water are added if necessary. And put into a kneader, and the Froude number is 0.1 to 2.0, preferably 0.5 to
The mixture is kneaded at a medium speed to give a kneaded product having a water content of 30% or more in a funicular II state or a capillary state, and the kneaded product is subjected to the above-mentioned curing, hydrothermal treatment, crushing treatment, or vibration. Molding, curing, hydrothermal treatment, and crushing treatment can also be performed (see FIG. 6).

Further, in these methods, any of the above treatments may be carried out after first crushing the inorganic waste (see FIG. 7). In addition, in these methods, first, the inorganic waste is classified by 0.05 to 0.3 mm to remove coarse particles, the fine particles are subjected to any of the above treatments, and the coarse particles are subjected to a hydrothermal treatment. You may make it mix with the processed material (refer FIG. 8). In addition, in these methods, the granular material after hydrothermal treatment and crushing is added in an amount of 0.05 to 0.
The particles may be classified by 3 mm to remove the particles, and then the particles may be returned to the charging material or the kneader (see FIG. 9).

The present invention is a method for producing a porous granular material as described above, and specifically, by taking the following means, a granular material having excellent characteristics with a technology having a small environmental load. Can be manufactured. (1) Technology with low environmental load The higher the processing temperature, the more energy is required, and in order to reduce the environmental load, lowering the processing temperature is effective.
Therefore, hydrothermal treatment is performed at a temperature of 130 to 220 ° C. 1
If the temperature is lower than 30 ° C, the reaction rate is slow, unreacted lime remains, the strength is low, and the pH of the granular material eluate is high. If it exceeds 220 ° C, the pressure becomes high and the cost of the apparatus becomes high.

(2) The addition amount of the lime source material is adjusted in the range of 2.5 to 25 parts by weight according to the SiO ₂ content and the water content of the high-strength inorganic waste.
By gradually adding water so as to be in the funicular I and II state to the capillary state, and kneading at a medium speed, the lime source material and water are uniformly dispersed, and porous granules having high strength by hydrothermal treatment. The body is obtained. If the amount of the lime source material added is less than 2.5 parts by weight, high strength will not be exhibited, and if it is more than 25 parts by weight, the cost will increase and a large amount of unreacted lime will remain, resulting in poor quality of granules. Become. Further, by aging the kneaded product at room temperature to 95 ° C. for 0.2 to 36 hours, the hydration reaction proceeds and the surface water disappears, so particles do not stick to each other in the subsequent hydrothermal treatment, and high strength is obtained. Express. The treatment at a temperature higher than 95 ° C. for a time longer than 36 hours becomes high in cost, and the treatment for less than 0.2 hours causes insufficient curing and lowers the strength.

(3) Characteristics as a gardening material a) High water absorption The plastic limit of inorganic wastes is as wide as 20 to 70%. For inorganic wastes having a plasticity limit of about 30% or more, medium speed kneading can easily produce granules having a water absorption rate of 30% or more. Inorganic waste with a plasticity limit of less than about 30% is classified by 0.05 to 0.3 mm to remove coarse particles or crushed to reduce particles of 0.1 mm or more. Alternatively, the plastic limit of the inorganic waste can be set to about 30% by adding fine particles of porous granular material to the raw material. In order to rapidly and uniformly proceed the hydrothermal treatment to form a porous granular material, the kneaded product is treated with Funicular I and II by medium speed kneading.
It is important to set the state to the capillary state. Here, the medium speed kneading is kneading under the condition that the Froude number is 0.1 to 2.0, preferably 0.5 to 1.5.
The Froude number is a dimensionless number represented by N ² R / g (N: rotational speed, R: stirring blade diameter, g: gravitational acceleration),
The present invention corresponds to the kneading speed. In low-speed kneading, it takes a long time to homogenize the kneaded product, and in high-speed kneading, the amount of water decreases and the mixture is densified. Since it is a kneaded product, it becomes difficult to control the operating conditions of the kneader. In the pendular state where the kneaded product does not enter the funicular I state,
The hydration reaction does not proceed sufficiently, the strength is low, and the cation exchange capacity is small. Further, in a kneaded product state that is higher than the capillary state, that is, in a slurry, the kneaded product flows, and handling becomes difficult, and stable operation of the device becomes difficult. In addition,
According to JIS, the funicular II state and the capillary state are
A 1205 refers to the state of plasticity limit and liquidity limit measured by the soil liquidity limit / plasticity limit test method.

B) Appropriate particle size (securing high water permeability) In order to prevent coarse particles of 3 to 10 mm or more from forming in the granular material, the kneaded product is classified by 3 to 10 mm and the coarse particles are crushed. Returning to the kneading step (or raw material step), the particles of 3 to 10 mm or less may be hydrothermally treated. On the other hand, fine particles of 0.1 to 1 mm or less may be removed by classification after hydrothermal treatment. Furthermore, 0.05-0.3mm generated by crushing after hydrothermal treatment
The following fine particles may be classified and removed after the crushing treatment. By returning the fine particles to the kneading step (or the raw material step), the entire amount of waste can be made into particles.

C) High cation exchange capacity The product of hydrothermal treatment is a tobermorite material. Since the tobermorite-based substance has a cation exchange ability, it is important to increase this amount. By adding 2.5 to 25% by weight of a lime-based material to the inorganic waste, it is possible to generate a tobermorite-based substance and secure a high cation exchange capacity. When the amount of lime-based material increases,
As the cost increases, unreacted lime-based material remains and the pH of the eluate increases. As the lime-based material, quick lime, slaked lime, cement, powder slag, waste concrete fine powder and the like are suitable. In particular, quick lime is superior in cost, granular performance, and stable operability of the device. d) Ensuring long-term water permeability Since high strength is maintained for a long time, large water permeability is ensured for a long time.

(4) Characteristics as soil wood (compacting characteristics, modified CBR characteristics) Crusher Run C-40 (maximum diameter 4
0 mm), C-20 (maximum diameter 20 mm), F-2.5 (maximum diameter 5 mm) and the like. When used in combination with a classifier, the particle size of crushed stone can be adjusted. In addition, when the particle shape is irregular rather than substantially spherical, the particles are more entangled with each other, the compaction characteristics are better, and the modified CBR
Becomes higher. Therefore, depending on the maximum diameter, the particle size distribution, and the particle shape, the irregularly shaped particles obtained by the crushing treatment can be compacted to a modified CBR of 30 to 130% with compaction equivalent to that of the natural material.
It can be applied as various types of earth and wood. Further, since it has a high water absorption rate and a large water permeability, it can be applied to a playground where drainage is required.

(5) Color of Granules The color of the granules varies depending on the color of the inorganic waste (varies depending on the composition etc.), and exhibits a color of black to brown to gray.
Depending on the application, color is an important evaluation item. The iron compound contained in the inorganic waste is used to adjust the color of the granular material. That is, if the iron compound has a large particle size, the color becomes darker by crushing. Further, black to brown can be obtained by selecting an oxidizing agent such as iron nitrate, magnesium nitrate or aluminum nitrate and oxidizing the iron compound by heat treatment or hydrothermal treatment at room temperature to 220 ° C. Since the color varies depending on the type and amount of the oxidizing agent added and the heat treatment temperature, adjust them with the target color. In addition,
If the amount of the oxidizing agent added is too small, the color does not change, and if it is too large, the cost increases and the quality of the granular material deteriorates.

(6) Safety Since the tobermorite-based substance due to hydrothermal reaction fixes harmful substances, the eluate of the porous granular material (according to the Environmental Agency Notification No. 46 method) under proper processing conditions is a soil environmental standard. To be satisfied. In addition, porous granular materials include exhaust gas adsorbents, water treatment materials,
It can also be used as a building material additive.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described. However, the present invention is not limited to the following embodiments, and can be appropriately modified and implemented. . FIG. 1 shows steps of a method for producing a porous granular material using inorganic waste as a raw material according to the first embodiment of the present invention. Addition of lime-based materials such as quick lime, slaked lime, cement, powder slag, and waste concrete fine powder to inorganic waste such as foundry sand dust, crushed stone sludge, construction sludge, tap water sludge, and coal ash, and water if necessary. And a kneading at a medium speed so that the Froude number is 0.1 to 2.0, preferably 0.5 to 1.5, and a substantially spherical granulation in a funicular I state having a water content of 20% or more. The product (kneaded product).
The kneaded product is classified by a sieve or the like with a size of 3 to 10 mm, and then 3-1.
After crushing 0 mm or more, it is returned to the kneading step (or raw material step), and 3 to 10 mm or less is cured at room temperature to 95 ° C for 0.2 to 36 hours, and then at 130 to 220 ° C for 1 hour. Hydrothermal treatment is performed for -24 hours to obtain a porous granular material.

FIG. 2 shows steps of a method for producing a porous granular material using inorganic waste as a raw material according to the second embodiment of the present invention. A water content of 20 is added to the inorganic waste by adding lime-based material and water if necessary, and kneading at medium speed.
% Or more to obtain a substantially spherical granulated product (kneaded product) in the funicular I state. The kneaded product is classified into 3 to 10 mm, and 3 to 10
After crushing those having a diameter of 3 mm or more, they are returned to the kneading step (or raw material step), and those having a diameter of 3 to 10 mm or less are cured and then subjected to hydrothermal treatment. Granules obtained by hydrothermal treatment 0.1 to 1 mm
Then, the particles having a diameter of 0.1 to 1 mm or less are returned to the kneading step (or the raw material step) to obtain a porous granular material from which fine powder is removed.
Other configurations, operations and the like are similar to those of the first embodiment.

FIG. 3 shows steps of a method for producing a porous granular material using inorganic waste as a raw material according to the third embodiment of the present invention. Water content of 30% is added to inorganic waste by adding lime material and water as needed and kneading at medium speed.
% Or more of a funicular II state-capillary state kneaded product (lump), and the kneaded product at room temperature to 95 ° C. of 0.2 to
Curing for 36 hours, then 1 ~ 130 ~ 220 ℃
After hydrothermal treatment for 24 hours, crushing treatment is performed to obtain amorphous porous particles. Other configurations, operations and the like are similar to those of the first embodiment.

FIG. 4 shows steps of a method for producing a porous granular material using inorganic waste as a raw material according to the fourth embodiment of the present invention. Water content of 30% is added to inorganic waste by adding lime material and water as needed and kneading at medium speed.
% Or more of a funicular II state to a capillary state kneaded material (lump), the kneaded material is molded without applying pressure by vibration, then cured, and then subjected to hydrothermal treatment and crushing treatment. To obtain an amorphous porous granular material. In the vibration molding, the kneaded product is put into a mold, and vibration is applied from below to perform molding. Other configurations, operations and the like are similar to those of the first and third embodiments.

FIG. 5 shows an example of steps of a method for producing a porous granular material using inorganic waste as a raw material according to the fifth embodiment of the present invention. To the inorganic waste, an oxidizing agent such as iron nitrate, magnesium nitrate, and aluminum nitrate and, if necessary, water are added, and kneading is performed to obtain a kneaded product. Heat treatment or hydrothermal treatment for ˜15 hours. To the processed product that has been subjected to such an oxidation treatment,
The lime-based material and water as necessary are added, and the treatments according to the first to fourth embodiments are performed. Although FIG. 5 illustrates, as an example, the steps of kneading, curing, hydrothermal treatment, and crushing after the oxidation treatment, it is possible to perform the treatments shown in FIGS. 1 to 4 after the oxidation treatment. it can.

FIG. 6 shows an example of steps of a method for producing a porous granular material using inorganic waste as a raw material according to the sixth embodiment of the present invention. A lime material and an oxidizer and, if necessary, water are added to the inorganic waste, and the mixture is mixed at a medium speed to obtain a kneaded product (lump) in a funicular II state to a capillary state with a water content of 30% or more. To do. The kneaded product is cured, then hydrothermally treated, and then crushed to obtain an amorphous porous granular material. In the present embodiment, the oxidation treatment is not separately performed as a pretreatment, but the oxidation treatment is also performed in a kneading step, a curing step, etc. by adding an oxidizing agent together with a lime material or the like. Note that FIG. 6 shows, as an example, a configuration in which an oxidizing agent is added together with the lime-based material in the process of the third embodiment (FIG. 3), but lime is used in the process of the fourth embodiment (FIG. 4). The composition may be such that an oxidizing agent is added together with the system material. In that case, the kneaded product is subjected to vibration molding, followed by curing, hydrothermal treatment and crushing. Other configurations, operations and the like are similar to those of the first, third, fourth and fifth embodiments.

FIG. 7 shows an example of steps of a method for producing a porous granular material using inorganic waste as a raw material according to the seventh embodiment of the present invention. In the present embodiment, after the inorganic waste is crushed to eliminate coarse particles, the first to sixth embodiments are performed.
The processing is performed in a form. In addition, in FIG.
After the crushing process, as an example, kneading, curing, hydrothermal treatment,
Each process of crushing is illustrated, but after the crushing process,
The processing as shown in FIG. 6 can be performed.

FIG. 8 shows an example of steps of a method for producing a porous granular material using inorganic waste as a raw material according to the eighth embodiment of the present invention. In the present embodiment, after the inorganic waste is classified by 0.05 to 0.3 mm to remove coarse particles,
The processing as in the first to sixth embodiments is performed on the fine particles. The coarse particles are mixed with the processed product after the hydrothermal treatment. In FIG. 8, after removing coarse particles by classification,
As an example, the steps of kneading, curing, hydrothermal treatment, and crushing are illustrated, but the treatments shown in FIGS. 1 to 6 can be performed after classification.

FIG. 9 shows an example of steps of a method for producing a porous granular material using inorganic waste as a raw material according to the ninth embodiment of the present invention. In the present embodiment, the crushed material (granular material) after hydrothermal treatment and crushing is classified to 0.05 to 0.3 mm to remove fine particles, and the fine particles are returned to the raw material step (or kneading step). To obtain a porous granular material. In FIG. 9, as an example, kneading, curing,
Although the classification is performed after the hydrothermal treatment and crushing steps, the treatments shown in FIGS. 3 to 8 can be performed before the classification.

[0030]

EXAMPLES Example 1 Foundry sand dust A (SiO ₂ : 65 wt%, plasticity limit: 32)
%), 5.5 parts by weight of quicklime, relative to 100 parts by weight of a raw material obtained by adding a kneaded material classified and crushed to a size of 5 mm to be described later,
Add 30 parts by weight of water, knead at a medium speed of Froude number 1.1, classify the resulting kneaded product by sieving at 5 mm, crush 5 mm or more, and then return to the kneading machine for 5 mm. The following kneaded product is aged at room temperature for 1 hour and then at 190 ° C for 1 hour.
Hydrothermal treatment was performed for 0 hours to produce substantially spherical particles (black) having a size of 5 mm or less. The water absorption rate of this granular material is 35%, the cation exchange capacity is 16 meq / 100g, and the crush strength is 2.5 kg.
(2 mm particles) and the pH of the eluate was 9.3.

Example 2 The granules obtained in Example 1 were classified to 0.1 mm to give 0.1
The total amount of not more than mm is added to the foundry sand dust A, and the dust 10
5.5 parts by weight of quicklime and 31 parts by weight of water were added to 0 parts by weight, and the mixture was kneaded at a medium speed of Froude number of 1.2, and then the obtained kneaded product was aged at room temperature for 0.5 hours. , Then 18
Granulated solid (grey) after hydrothermal treatment at 0 ° C for 10 hours
Was manufactured. The granular material had a water absorption of 36%, a cation exchange capacity of 15 meq / 100 g, a crushing strength of 2.3 kg, and an eluent pH of 9.2.

Example 3 Foundry sand dust B (SiO ₂ : 61 wt%, plasticity limit: 35)
%) 6.5 parts by weight of quick lime and 3 parts of water with respect to 100 parts by weight
After adding 4 parts by weight and kneading at a medium speed of Froude number of 0.8, the resulting kneaded product was aged at room temperature for 2 hours, and then,
Hydrothermal treatment was performed at 195 ° C. for 10 hours to produce a solidified body. This solidified body was crushed by an impact crusher to obtain a granular body (gray) of 10 mm or less. The water absorption rate of this granular material is 37%,
Cation exchange capacity is 23meq / 100g, crushing strength is 2.
It was 0 kg (2 mm particles), and the pH of the eluate was 9.6.

Example 4 Coal ash (SiO ₂ : 55 wt%, plasticity limit: 33%) 10
To 0 part by weight, 10 parts by weight of slaked lime and 35 parts by weight of water were added, and the mixture was kneaded at a medium speed of Froude number of 0.8, and then vibration-molded into a block shape. After curing for a period of time, hydrothermal treatment was performed at 180 ° C. for 10 hours to produce a solidified body. This solidified body was crushed by an impact crusher to give a granular body (gray) of 40 mm or less. The crushing strength of this granular material was 20 kg (10 mm particles) and the modified CBR was 75%, which satisfied the lower layer roadbed material standard of 20%.

Example 5 20 parts by weight of quick lime was added to 100 parts by weight of construction sludge (water content: 50% by weight, SiO ₂ : 53% by weight (in solid content), plasticity limit: 48%) to obtain a Froude number of 0.8. After kneading at a medium speed, the obtained kneaded product was aged at 60 ° C. for 1 hour, and then hydrothermally treated at 190 ° C. for 10 hours to produce a solidified product. This solidified body is crushed with an impact type crusher to 10 mm
The following granules (gray) were used. The water absorption of this granular material is 3
The cation exchange capacity was 8%, the cation exchange capacity was 14 meq / 100 g, the crush strength was 2.0 kg (2 mm particles), and the pH of the eluate was 9.4.

Example 6 2 parts by weight of magnesium nitrate and 25 parts by weight of water were added to 100 parts by weight of casting sand dust B, and the mixture was kneaded and then heat-treated at 95 ° C. for 3 hours. The same treatment as in Example 2 was performed using 100 parts by weight of this treated product. The obtained granules were dark brown in color, had a water absorption rate of 38%, a cation exchange capacity of 25 meq / 100 g, and a crush strength of 2.0 kg (2 mm
Particles) and the pH of the eluate was 9.3.

Comparative Example 1 6.5 parts by weight of quick lime and 24 parts by weight of water were added to 100 parts by weight of casting sand dust B, and the mixture was kneaded at a high speed with a Froude number of 3.5. It was aged at room temperature for 2 hours and then hydrothermally treated at 190 ° C. for 10 hours to produce a granular body (gray). The water absorption rate of this granular material is 26.
%, The cation exchange capacity was 8 meq / 100 g, the crush strength was 0.5 kg (2 mm particles), and the pH of the eluate was 10.4.

Comparative Example 2 10 parts by weight of slaked lime and 32 parts by weight of water were added to 100 parts by weight of casting sand dust B, and kneading was carried out at a high speed with a Froude number of 3.5, followed by extrusion molding at a pressure of 300 kg / cm ^2. Was formed into a cylindrical shape having a diameter of 20 mm and a length of 30 to 60 mm, which was aged at room temperature for 2 hours and then hydrothermally treated at 200 ° C. for 10 hours to produce a solidified body (gray). The modified CBR of this solidified body is 15%, which is 2
0% was not satisfied.

[0038]

Since the present invention is configured as described above, it has the following effects. (1) Since the inorganic waste is formed into a porous granular material by hydrothermal treatment, it is possible to recycle the inorganic waste by a processing technique with a small environmental load. (2) A horticultural material, earth and timber, a soil improving material, etc. by using a lime source material as an additive material to an inorganic waste and forming a kneaded material in a funicular I, II state to a capillary state by medium speed kneading. A porous granular material having a quality suitable for the above can be produced. (3) Returning 3 to 10 mm or more of the kneaded material to the kneading step (or raw material step), kneading 0.1 to 1 mm or less fine powder after hydrothermal treatment or 0.05 to 0.3 mm or less fine powder after crushing By returning to the process (or raw material process), the grain size of the product can be secured and the entire amount of waste can be made into the product. (4) The color of the granular material can be adjusted by using the oxidizing agent. (5) By adjusting the amount of lime source material, the powder amount of 0.05 to 0.3 mm or less (or 0.1 to 1 mm or less), and the amount of water, water content such as mud waste and powder waste, plasticity Wastes having different limits can be kneaded in the funicular I, II state to the capillary state, and the quality of the granular body or the solidified body can be secured.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing steps of a method for producing a porous granular material using inorganic waste as a raw material according to the first embodiment of the present invention.

FIG. 2 is a schematic explanatory view showing steps of a method for producing a porous granular material using inorganic waste as a raw material according to the second embodiment of the present invention.

FIG. 3 is a schematic explanatory view showing steps of a method for producing a porous granular material using inorganic waste as a raw material according to the third embodiment of the present invention.

FIG. 4 is a schematic explanatory view showing steps of a method for producing a porous granular material using inorganic waste as a raw material according to the fourth embodiment of the present invention.

FIG. 5 is a schematic explanatory view showing an example of steps of a method for producing a porous granular material using inorganic waste as a raw material according to the fifth embodiment of the present invention.

FIG. 6 is a schematic explanatory view showing an example of steps of a method for producing a porous granular material using inorganic waste as a raw material according to the sixth embodiment of the present invention.

FIG. 7 is a schematic explanatory view showing an example of steps of a method for producing a porous granular material using inorganic waste as a raw material according to the seventh embodiment of the present invention.

FIG. 8 is a schematic explanatory view showing an example of steps of a method for producing a porous granular material using inorganic waste as a raw material according to the eighth embodiment of the present invention.

FIG. 9 is a schematic explanatory view showing an example of steps of a method for producing a porous granular material using inorganic waste as a raw material according to the ninth embodiment of the present invention.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B09B 3/00 C02F 11/00 101Z 4G012 C02F 11/00 101 C04B 28/18 ZAB 4H026 C04B 28/18 ZAB 40 / 02 4H061 40/02 C05D 3/00 C05D 3/00 3/04 3/04 C05F 7/00 C05F 7/00 C09K 17/02 H C09K 17/02 17/06 H 17/06 101: 00 // C09K 101: 00 B09B 3/00 304G Z F term (reference) 2B022 BA01 BA05 BB01 4D004 AA02 AA16 AA36 BA02 BA10 CA04 CA08 CA14 CA15 CA34 CC11 CC13 DA03 DA06 DA09 DA10 DA20 4D021 AB02 EA10 CC09 BK01 BB01 BB01 BB01 DA04 DA05 DA66 DA70 4G004 AA02 4G012 MB04 PA25 PA26 PA28 PA30 PB07 PC01 PC11 PE04 PE07 RA03 RA05 RB03 4H026 AA03 AA04 AA05 AA18 AB04 4H 061 AA02 CC02 CC03 CC08 CC14 CC51 DD20 EE41 FF08 FF21 GG13 GG42 GG70 LL02 LL05 LL15 LL24

Claims (11)

[Claims] 1. To 100 parts by weight of an inorganic waste as a raw material, 2.5 to 25 parts by weight of a lime source material and 0.01 to 30 parts by weight of water as necessary are added and charged into a kneading machine to obtain a fluid. Kneading is carried out at a medium speed so that the number becomes 0.1 to 2.0 to obtain a substantially spherical granulated kneaded product in the funicular I state having a water content of 20% or more, and the kneaded product is 3 to 10 mm. After classifying, 3 to 10 mm or more is crushed, and then returned to the kneader or the input material, and 3 to 10 mm or less at room temperature to
After curing at 95 ° C for 0.2 to 36 hours, 130 to 2
A method for producing a porous granular material using an inorganic waste as a raw material, which comprises hydrothermal treatment at 20 ° C. for 1 to 24 hours to obtain a granular material. 2. The granular material obtained by hydrothermal treatment is 0.1 to 1
3. Classifying in mm, returning 0.1 to 1 mm or less to a kneader or charging material to obtain granules of 0.1 to 1 mm or more.
A method for producing a porous granular material using the described inorganic waste as a raw material. 3. To 100 parts by weight of the inorganic waste as a raw material, 2.5 to 25 parts by weight of the lime source material and 0.01 to 60 parts by weight of water as necessary are added and charged into a kneading machine to obtain a fluid. The mixture is kneaded at a medium speed so that the number becomes 0.1 to 2.0 to obtain a kneaded product in a funicular II state or a capillary state having a water content of 30% or more, and the kneaded product is from room temperature to 95 ° C. at 0.
Curing for 2-36 hours and then hydrothermal treatment at 130-220 ° C. for 1-24 hours, followed by crushing treatment to obtain granules, porous material made from inorganic waste Granular body manufacturing method. 4. To 100 parts by weight of the inorganic waste as a raw material, 2.5 to 25 parts by weight of the lime source material and 0.01 to 60 parts by weight of water as necessary are added, and the mixture is put into a kneading machine, and then the fluid is added. The mixture is kneaded at a medium speed so that the number becomes 0.1 to 2.0 to give a kneaded product in a funicular II state or a capillary state having a water content of 30% or more, and the kneaded product is subjected to vibration molding, and then at room temperature to 95%. Curing for 0.2 to 36 hours at ℃, then 1
A method for producing a porous granular material using an inorganic waste as a raw material, which comprises performing a hydrothermal treatment at 30 to 220 ° C. for 1 to 24 hours and then performing a crushing treatment to obtain a granular material. 5. As a pretreatment, 100 parts by weight of the inorganic waste is added with 0.5 to 20 parts by weight of an oxidizer and 0.01 to 60 parts by weight of water if necessary, and the mixture is kneaded. The lime source material and water as needed are added to the obtained processed material after heat-treating or hydrothermally treating the material for 0.2 to 15 hours at room temperature to 220 ° C., and then the method according to claim 1. A method for producing a porous granular material using an inorganic waste as a raw material, characterized by performing a treatment. 6. 100 parts by weight of inorganic waste as a raw material, 2.5 to 25 parts by weight of a lime source material, and 0.5 to 2 parts of an oxidizer.
0 part by weight, and 0.01 to 60 parts by weight of water as necessary are added to the kneader and kneaded at a medium speed so that the Froude number is 0.1 to 2.0, and the water content is 30. % Or more of the kneaded material in the funicular II state or the capillary state,
Curing, hydrothermal treatment, crushing treatment according to claim 3, or vibration molding, curing, hydrothermal treatment according to claim 4 to the kneaded product,
A method for producing a porous granular material using an inorganic waste as a raw material, characterized by crushing a granular material. 7. The method according to claim 1 after crushing the inorganic waste.
7. The method for producing a porous granular material using an inorganic waste as a raw material, which comprises performing the treatment according to any one of 6 above. 8. Inorganic waste is classified at 0.05 to 0.3 mm to remove coarse particles, and fine particles as claimed in claim 1 to 7.
The method for producing a porous granular material using an inorganic waste as a raw material, characterized in that the coarse particle is mixed with a treated product after hydrothermal treatment. 9. The granular material after hydrothermal treatment and crushing is 0.0
Fine particles are removed by classification with 5 to 0.3 mm, and the fine particles are returned to a charging raw material or a kneader to perform the treatment according to any one of claims 3 to 8 as a raw material. And a method for producing a porous granular material. 10. The inorganic waste according to claim 1, wherein the inorganic waste is at least one of foundry sand dust, crushed stone sludge, construction sludge, tap water sludge and coal ash. And a method for producing a porous granular material. 11. Quick lime, slaked lime, as a lime source material,
The method for producing a porous granular body using an inorganic waste as a raw material according to claim 1, wherein at least one of cement, slag powder and waste concrete fine powder is used.