JP2009148713A - Granule, sintered body, and methods for producing them - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique which is simple in granulation and high in waste utility (recycling efficiency) when a waste such as incineration ash, sludge, or construction soil is granulated by adding water for recycling. <P>SOLUTION: Granules contain one or more kinds of materials selected from a group consisting of incineration ash, sludge and construction soil, and a lignin compound. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a granulated body and a sintered body. In particular, the present invention relates to a granulated body and a sintered body made from waste such as incinerated ash, sludge, or construction generated soil.

  In recent years, the amount of incinerated ash, sludge and construction generated soil has increased. And it is becoming difficult to dispose of it easily. Therefore, recycling of the waste is being tried in various directions. However, since the quality of waste is not stable, it is very difficult to recycle it.

  Now, as reuse (recycling) of incineration ash and construction waste soil, it is proposed to use it as a civil engineering material such as concrete aggregate or roadbed material in addition to cement raw materials. For example, recycling to aggregate is performed by granulating powder waste and performing steps such as cement solidification and firing. And the said granulation may be granulated just by adding water as it is. However, when the particle size is large or the particle size distribution is narrow, granulation is often difficult. Moreover, fly ash cannot be granulated as it is because the particles are spherical in the coal ash generated from pulverized coal combustion at a coal-fired power plant.

  Waste such as papermaking sludge is generated from the papermaking process and used paper recycling process, and organic substances such as fine fibers that are not recovered in the papermaking process, and inorganic substances such as kaolin, talc, and calcium carbonate that are used as pigments and dyes Consists of And papermaking sludge is often incinerated for weight reduction. As for the papermaking sludge (papermaking sludge incineration ash) thus incinerated, what is currently reused industrially is only used as a cement raw material. And most of the remaining amount is landfilled. In addition, industrial use as an aggregate is hardly made.

In addition, from the viewpoint of reducing CO ₂ emissions, biomass power generation using carbon-neutral biogenic raw materials such as paper sludge and wood chips is increasing. And since the quality of incinerated ash discharged by biomass power generation is not stable, recycling is more difficult.

  By the way, in order to recycle the waste, the powder of these wastes is granulated. For this granulation, a roll press, a pan pelletizer, or the like is used. At this time, the properties of the raw material (powder) greatly affect the granulation property. And granulation is often very difficult. In particular, when granulating continuously with a pan pelletizer, it may not be possible to granulate at all depending on the raw material. Even if it can be granulated, the particle size becomes large and there is a problem that it cannot be controlled.

Conventionally, several granulation techniques have been proposed.
For example, there is no need to adjust the particle size of coal ash, and coal ash with a relatively large maximum particle size can be used. In order to obtain an easy-to-operate artificial lightweight aggregate, sewage sludge incinerated ash is mixed with coal ash so that the proportion of coal ash is 10% to 80% by weight, and the raw material is fired. A method of manufacturing an artificial lightweight aggregate characterized by the above has been proposed (Japanese Patent Laid-Open No. 11-35356).

  In addition, ash is cemented for the purpose of solidifying the ash and having a sufficient strength that can be effectively used as a construction material such as pavement, and that does not cause the problem of elution of heavy metals at a low cost. And a method of solidifying and molding the resulting mixture, wherein the ash is pulverized, and cement, water and a calcium compound are added to and mixed with the ash or pulverized ash. A characteristic ash solidification molding method has been proposed (Japanese Patent Laid-Open No. 2002-18411).

In addition, in order to utilize the characteristics or functionality of paper sludge ash, finely pulverized paper sludge ash with low moisture absorption for the purpose of establishing a waste recycling system mainly composed of paper sludge ash. A papermaking sludge ash-containing granulated product obtained by granulating a pulverized product with only water injection has been proposed (Japanese Patent Laid-Open No. 2005-103464).
JP-A-11-35356 JP 2002-18411 A JP 2005-103464 A

  By the way, as mentioned above, although various granulation techniques have been proposed, granulation is still difficult in many cases.

  Therefore, the problem to be solved by the present invention is that in order to recycle waste such as incineration ash, sludge, or construction generated soil, granulation with the addition of water is easy and To provide technology with high waste utilization (recycling efficiency).

  While studies for solving the above-mentioned problems are being intensively promoted by the present inventor, when a lignin-based compound (including lignin) is used, granulation becomes easy, and it is worn out even in the firing step. As a result, it has been found that the shape of the aggregate caused by the deterioration of the aggregate can be suppressed.

The present invention has been made based on the above findings.
That is, the above problem is
One or more materials selected from the group of incinerated ash, sludge and construction generated soil;
The problem is solved by a granulated body comprising a lignin compound.

In particular, one or more materials selected from the group of incinerated ash, sludge and construction generated soil,
Containing a lignin compound,
The lignin compound is solved at a ratio of 0.1 to 10 parts by mass with respect to 100 parts by mass of the material.

In addition, the above problem is
Solved by a method for producing a granulated product, characterized by adding an aqueous solution of a lignin compound to one or more materials selected from the group of incinerated ash, sludge and construction generated soil, followed by granulation. The

In particular, the lignin compound is in a ratio of 0.1 to 10 parts by mass with respect to 100 parts by mass of one or more kinds of materials selected from the group of incinerated ash, sludge and construction generated soil. On the other hand, it is solved by a method for producing a granulated product, characterized in that an aqueous solution of the lignin compound is added and granulated thereafter.

In addition, the above problem is
This is solved by a sintered body characterized in that the granulated body is fired.

In addition, the above problem is
It solves by the manufacturing method of the sintered compact characterized by baking said granulated body at 650-1300 degreeC.

  Since granulation was performed using a lignin compound together with one or more kinds of waste selected from the group of incinerated ash, sludge and construction generated soil, granulation was very easy. Further, even when the granulated body is baked to improve the strength, it is difficult to cause shape deterioration such as wear in the baking process. Also, the strength became large.

  The present invention is a granulated body (granulated product). This granulated body contains one or more materials (waste) selected from the group of incinerated ash, sludge, and construction generated soil. In particular, a kind selected from the group of incineration ash such as paper sludge incineration ash having a coarse particle size that is difficult to granulate alone, sludge such as purified water sludge generated from water and sewage, and construction generated soil such as construction sludge Contains two or more materials (waste). And a lignin type compound is included. The amount of the lignin-based compound is preferably 0.1 to 10 parts by mass (particularly 0.2 parts by mass or more, and further 0.3 parts by mass or more) with respect to 100 parts by mass of the material (waste). (Parts by mass or less).

  Moreover, this invention is a manufacturing method of a granulated body (granulated material). This manufacturing method is a method of granulating a mixture containing the material (waste material) and the lignin compound. Preferably, the lignin-based compound is added to the material in the form of a solution, not in a solid form, and granulated. In addition, it is the method of adding and granulating water at the time of the addition of lignin type compound aqueous solution before or after that as needed.

  Moreover, this invention is a sintered compact. This sintered body is obtained by firing the granulated body (granulated product).

  Moreover, this invention is a manufacturing method of a sintered compact. This sintered body fires the granulated body (granulated material). The temperature at the time of firing is 650 to 1300 ° C. (particularly 800 ° C. or more and 1200 ° C. or less).

This will be described in more detail.
First, the above-described raw material (the above-mentioned waste powder) and a lignin compound are prepared. And the lignin type compound aqueous solution is added to this raw material, and the granulated material of a diameter of several mm-dozen mm is created. This granulated product is sintered at a temperature of 650 ° C. or higher to obtain an artificial aggregate or the like.

  For the granulation, for example, a roll press, a pan pelletizer, an Eirich mixer or the like is used. That is, a lignin-based compound aqueous solution is added to the raw material, and granulation is performed using the granulator. When granulation is performed using a pan pelletizer, the granulated product has a spherical shape, and a granulated product of an arbitrary size can be obtained by controlling the granulation. Therefore, granulation using a pan pelletizer is preferred.

  Incineration ash, sludge, and construction waste soil are used as the raw material for granulated materials. Only one of these may be selected and used, or two or more may be selected and used. However, it is usually preferred that one type is selected and used.

  Examples of the incineration ash include pulverized coal combustion ash, fluidized bed combustion coal ash, coke ash, waste incineration ash, sewage sludge incineration ash, paper sludge incineration ash, and waste plastic incineration ash from coal-fired power plants. The papermaking sludge incineration ash is ash obtained by incinerating sludge generated in the papermaking process or recycling of used paper. And as a main component, inorganic components, such as Ca and Al, are included. In addition, incineration ash generated from biomass power generation using biomass fuel such as firewood, charcoal, waste material, and food pomace is also included. Incinerated ash of organic raw materials, such as papermaking sludge incinerated ash, is a preferred raw material because it has fine pores (pores) inside and has high water absorption (porous) characteristics. That is, since the granulated and fired product of the organic raw material incinerated ash becomes a highly water-absorbing aggregate, it is preferable to use the incinerated ash of the organic raw material as the granulated material.

  Examples of the sludge include purified water sludge and sewage sludge. Preferably, purified water sludge is used.

  Examples of construction generated soil include construction residual soil, contaminated soil, and dredged soil. Among these, it is preferable that the content of silt / clay having a particle diameter of 75 μm or less is 70% or more. The reason is that if the amount of sand is too much, it becomes difficult to control the particle size when granulating.

  The above-mentioned various incineration ash, sludge and construction generated soil are pulverized and used as a raw material for the granulated body as necessary.

A raw material having high water retention (powder: powder) usually has good granulation properties.
However, when a raw material in which the amount of the 88 μm residue exceeds 30% is used, the granulation property is extremely deteriorated. The reason for this is thought to be that the lack of small particles that complement each other, resulting in poor adhesion strength between the particles and difficulty in granulation. However, when the lignin-based compound aqueous solution is added to such a raw material and granulation is performed, the granulation property is improved.

  In addition, when a clay mineral was used in combination, it became even better. In particular, when a clay mineral having a swelling power of 10 ml / 2 g or more was used in combination, it became even better. In addition, the preferable compounding quantity of this kind of clay mineral was 3-30 mass parts (especially 5-20 mass parts) with respect to 100 mass parts of the said waste materials. In addition, it is conceivable to further use cement.

  In order to further improve the mechanical strength of the granulated product, firing is performed. For firing, a tunnel kiln, a roller house kiln, a fluidized bed, or a rotary kiln can be used. In addition, it is preferable to use a rotary kiln from the viewpoint of ease of manufacture. And if it bakes at the temperature of 650-1200 degreeC with such a baking kiln, a strong sintered body (aggregate) can be obtained.

Hereinafter, the present invention will be described with specific examples.
[Example]
Table-1
Sample Waste material Lignin Bentonite No. 1 Papermaking sludge incineration ash 0 parts by mass 0 parts by mass No2 Papermaking sludge incineration ash 0.2 parts by mass No3 Papermaking sludge incineration ash 0.5 parts by mass 0 parts by mass No4 Papermaking sludge incineration ash 0 parts by mass 0 parts by mass No5 Papermaking sludge incinerated ash 1.0 part by mass 5 parts by mass No6 Silt dry powder product 0 parts by mass 0 parts by mass No7 Silt dry powder product 0.5 parts by mass 0 parts by mass No8 dry water sludge dry powder product 0 Mass part 0 part by mass No. 9 purified water sludge dry powder product 0.5 part by mass 0 part by mass * The papermaking sludge incineration ash is d50% = 47.2 μm
* Silt (construction mud) dry powder product is 82% silt and clay
* Clean water sludge dry powder product is 75% silt and clay content
* Bentonite is mainly composed of montmorillonite and has a swelling power of 13ml / 2g.
The waste material dry powder (or a mixture with bentonite) as a main material was put into a 800 mm diameter pan pelletizer. Then, the lignin aqueous solution and, in some cases, water was sprayed with a watering device, and the mixture was rotated and granulated. In addition, if necessary, the material was continuously operated and granulated while adding raw materials.

  At this time, since it investigated about granulation property, the result is shown in Table-2.

  After granulation, it was baked at temperatures of 600 ° C., 700 ° C., 1000 ° C., and 1200 ° C. in an electric furnace. And since the crushing strength of this baked product was investigated, the result is shown in Table-2.

Table-2
Sample Granulation Crushing strength (N)
600 700 1000 1200
No1 Can't granulate----
No2 Granulated but difficult to control particle size 7 15 15 25
No3 Good granulation, particle size controllable 10 19 23 120
No4 Good granulation, particle size controllable 12 25 28 141
No. 5 Very good granulation, controllable particle size 25 35 51 252
No6 Granulation slightly difficult, particle size control not possible----
No. 7 Good granulation, particle size controllable 13 16 32 171
No8 Granulated but difficult to control particle size 9 12 18 109
No9 Good granulation, particle size controllable 22 28 40 305

According to this, it turns out that what becomes this invention has good granulation property and the intensity | strength of the sintered compact which baked the granulated material is large.

Patent Applicant Taiheiyo Material Co., Ltd.
Representative Katsumi Udaka

Claims (5)

One or more materials selected from the group of incinerated ash, sludge and construction generated soil;
A granulated product comprising a lignin compound. One or more materials selected from the group of incinerated ash, sludge and construction generated soil;
Containing a lignin compound,
The granulated product, wherein the lignin compound is in a proportion of 0.1 to 10 parts by mass with respect to 100 parts by mass of the material. A method for producing a granulated product comprising adding an aqueous solution of a lignin compound to one or more materials selected from the group of incinerated ash, sludge and construction generated soil, followed by granulation. A sintered body obtained by firing the granulated body according to claim 1 or 2. A method for producing a sintered body, comprising calcining the granulated body of claim 1 or 2 at 650 to 1300 ° C.