JPH0539610A - Method for disposing of ash of incinerated dust and soil improving material - Google Patents

Abstract

PURPOSE:To effectively utilize ashes of incinerated dust. CONSTITUTION:Metals are first separately removed from ashes of incinerated dust and gross objects are sieved from the ashes after drying. The sieved residues (gross objects) are crushed into grain-like bodies in size not dangerous for handling by a crusher for example and mixed with ashes passed through the sieve to provide regulated grain-like ashes. By adding a hydraulic substance such as cement, lime, etc., to the regulated ashes is provided a soil improving material which is effectively utilized for light banking material, poor soil improving material, material for improving dredged earth and sludge, earth acidity adjusting material, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating refuse incinerated ash and a soil improvement material for effectively utilizing the refuse incinerated ash.

[0002]

2. Description of the Related Art Conventionally, it is generally practiced that refuse generated from a kitchen in a home is incinerated in an incinerator and the incinerated ash is landfilled.

However, with the increase of garbage in recent years,
It is becoming difficult to secure landfill sites for refuse incineration ash. In this case, in order to effectively use the space of the landfill disposal site, it is considered that the waste incineration ash is melted into glass to reduce the volume and then landfilled, but this is not the fundamental solution to the landfill disposal site shortage. There wasn't.

[0004]

Therefore, in recent years, studies have been conducted to make effective use of refuse incineration ash. As one example, it has been attempted to mix cement and asphalt emulsion with a material obtained by removing large unburned materials from refuse incineration ash and to use it as a roadbed material.

However, when the waste incineration ash is used as a roadbed material in this way, since the waste incineration ash contains debris such as metal, glass, and pottery, it is troublesome to handle the waste incineration ash. There was also a risk of injury.

[0006] As described above, the waste incineration ash has not been effectively used in the past, and some of the methods of utilizing the refuse incineration ash have been attempted in terms of handleability and safety. The problem still remained.

The present invention has been made in view of the above circumstances, and an object thereof is a method for treating refuse incinerated ash which enables effective use of the refuse incinerated ash in a state where it is easy to handle and highly safe. To provide. Another object of the present invention is to provide a soil improvement material that can be produced by effectively utilizing waste incineration ash, is easy to handle, and is highly safe.

[0008]

Means for Solving the Problems A method for treating refuse incinerated ash according to the present invention is to remove coarse metals contained in the refuse incinerated ash after separating and removing metals from the refuse incinerated ash discharged from a refuse incinerator. It is characterized in that a crushed material is crushed to produce a granular ash, and a hydraulic substance is added to the conditioned ash to produce a soil improvement material.

Further, the soil improving material of the present invention is characterized in that a hydraulic substance is added to the adjusted ash in which the refuse incineration ash from which the metals have been separated and removed is made into a granular form.

[0010]

[Function] Generally, garbage contains glass, pottery, aluminum foil and the like, and garbage from the kitchen etc. also contains fish bones and shells. Therefore, the refuse incineration ash contains hydraulic components such as SiO2, Al2 O3, and CaO, and these hydraulic components are activated by the high temperature during refuse incineration. In addition, the refuse incineration ash has light weight and water absorption due to large voids, and is also basic.

The present inventor paid attention to the properties of the refuse incineration ash, such as hydraulic property, lightness, water absorption, basicity, etc., and as a result of various studies, the incineration ash was effective as a soil improvement material. They have found that they can be used and completed the present invention.

That is, the refuse incineration ash contains hydraulic components as shown in the following table, although it varies depending on the season, region, etc.

[0013]

[Table 1] Although not shown in Table 1, chlorine gas and SOx
Slaked lime may be added at the time of incineration of waste to treat exhaust gas such as CaCl2 and CaSO.
4 will also be generated.

As described above, the refuse incineration ash containing hydraulic components is crushed into coarse particles of the coarse material contained therein to make the whole into granular particles, and the adjusted ash has improved hydraulic properties and stability. Therefore, by adding a hydraulic material such as cement or lime as a reinforcing material, it can be utilized for soil improvement.

In this case, according to the present invention, the metals are separated and removed, and the coarse substances such as pottery and glass contained in the refuse incineration ash are crushed and mixed, so that they are easy to handle and safe. It will be highly responsive.

As the principle of soil improvement, as in the case of soil improvement with lime, ion exchange with calcium ions,
Pozzolanic reaction is enhanced. Of these, the pozzolanic reaction is
As shown below, the Ca component and the activated Al2 O3 or SiO2 are the reaction to form a hydrated crystal in the presence of water.

[0017]

[Chemical 1] As a result, the plasticity index of the soil is reduced, the soil has properties close to those of sand, and drainage can be improved.

In addition to this reaction system, CaSO4.nH2
When it contains O and Al2 O3 which is easily activated, or when it contains anhydrous CSA (Calcium-Sulfo-Alminate), it can be further stabilized by the formation of ettringite. When slags having latent hydraulicity are mixed with refuse incineration ash, if PH is in the range of 12.5 or more, the particles exhibit hydraulicity due to surface stimulation of particles.

In addition to the soil improvement utilizing the hydraulic property, the soil improving material containing calcium is
It can also be used for adjusting the acidity of acidic soil, and by including coarse particles such as porcelain and glass that are crushed, it is possible to improve the particle size of clay, and further,
Due to the large porosity of ash, it can be used for water absorption and water retention adjustment.

[0020]

EXAMPLES Examples of the present invention will be described below. First, a method for treating refuse incinerated ash according to this embodiment will be described. The refuse is incinerated in, for example, a continuous incinerator and turned into refuse incineration ash, which is discharged by, for example, a conveyor. When the refuse incineration ash is discharged, it is processed in the following process.

(1) Separation and Removal of Metals First, the step of separating and removing metals from the refuse incineration ash is carried out. This separation and removal is performed, for example, by magnetic separation, whereby unburned metals such as iron are removed from the refuse incineration ash.

(2) Drying Next, a step of drying the refuse incineration ash from which metals have been removed is executed. In this process, water in the refuse incineration ash is removed, and unburned materials such as glass, ceramics and stones are also dried.

(3) Sieving of coarse material After the drying step, the step of sieving the refuse incineration ash is carried out. In this process, sieving is performed with a size that is not dangerous to handle, for example, a mesh size of 2.5 mm, and waste incineration ash is divided into powdery granular ash and coarse residues such as glass, ceramics and stones. Is separated into Fragments of unburned materials such as glass, ceramics and stones are also contained in the passing ash, but this size is not dangerous for normal handling.

(4) Crushing of Screen Residue Among the particles separated in the sieving process, the process of crushing the residue (coarse material) into powder particles of a size that is not dangerous to handle by a crusher is carried out. To be done.

(5) Mixing When the crushing process of the coarse material is completed, a process of mixing the crushed material in the form of powder with the passing ash obtained in the sieving process is executed. Through these steps of sieving, crushing, and mixing, the original refuse incineration ash is made into a powdery state in which the whole is in a state where there is no danger in handling, and thus dry adjusted ash is produced.

(6) Addition of hydraulic substance By adding a hydraulic substance such as cement or lime to the adjusted ash obtained by the above process, the soil improvement material according to this embodiment is produced. is there.

In this case, the garbage contains glass, pottery, aluminum foil and the like, and the garbage from the kitchen also contains fish bones and shells. Therefore, in the adjusted ash,
It contains hydraulic components such as SiO2, Al2 O3, and CaO, and these hydraulic components are activated by the high temperature during refuse incineration. In addition, the refuse incineration ash has light weight and water absorption due to large voids, and is also basic.

Therefore, the adjusted ash can be effectively used for improving the soil quality by improving hydraulic properties and stability or by adding, for example, a hydraulic substance as a reinforcing material.

In this case, the strength and the like of the soil improving material can be controlled by the addition amount of the hydraulic substance, and the kind and the addition amount of the hydraulic substance are suitable for the purpose of use as the soil improving material, as exemplified later. It should be appropriate. Mechanisms for soil improvement include ion exchange with calcium ions and Al2O3 or S activated with Ca component.
The pozzolanic reaction of iO2 to form hydrated crystals in the presence of moisture is well known.

Next, some examples of use of the soil improvement material produced as described above will be described. First, it can be used as a lightweight fill material. In this case, 3% by mass of ordinary Portland cement, for example, as a hydraulic material is added to the adjusted ash, and 20% of water is mixed and compacted to obtain a uniaxial compressive strength of 1.5 Kgf / cm 2 or more on the 7th day. The dry density is 1.0 to 1.3 t / m3
A lightweight fill can be constructed. In addition, it can be used as a material for improving soft soil by mixing it with water.

And, it can be used as a material for improving dredged soil and sludge. In this case, the adjusted ash, for example, 5
By laying thickly 15% ordinary Portland cement or a mixture of limes on the dredged soil or sludge, it is possible to absorb the water in the dredged soil or sludge, and to handle the dredged soil or sludge. Can be easy.

When mixed with dredged soil or sludge, the soil conditioner absorbs water from the dredged soil or sludge and hardens due to the hydraulic property, so that the dredged soil or sludge can be improved. Will also be available. Here, in the hydrated crystal by the pozzolan reaction,
PCBs and harmful heavy metals contained in dredged soil and sludge (H
The advantage that g, Cd, Pb, As, Cr (VI), etc. can be confined can also be obtained. An effect as a sand drain can also be obtained by inserting the soil improvement material in a column shape into the dredging soft ground.

Furthermore, a mixture of adjusted ash and lime added to it can be used for adjusting the acidity of horticultural soil, and by containing coarse particles such as porcelain and glass crushed, It can be used to improve the particle size of clay. In addition, various uses such as low quality mortar, drainage material for playgrounds, water absorption as a composting aid for liquefied manure, etc. are possible.

As described above, according to the present embodiment, the refuse incineration ash is crushed into coarse ash after removing metals, and adjusted ash is produced. A hydraulic substance is added to the adjusted ash to improve the soil improvement material. As a result, about 80% or more of the refuse incineration ash can be effectively reused as a resource.
Moreover, the process of treatment is simple, such as removal of metals, sieving, and crushing of coarse particles, so that the cost can be reduced.

The produced soil improvement material is easy to handle and highly safe, unlike the conventionally used materials for roadbed materials, and is hydraulic, lightweight, water absorbing, basic, etc. It can be used for various purposes as an inexpensive material in the fields of civil engineering, horticulture, etc.

As a result, it is possible to effectively utilize the refuse incineration ash, which has not been made in the past, and it is possible to greatly contribute to the solution of the problem of the shortage of landfill disposal sites due to the increase of the garbage in recent years.

The present invention is not limited to the above-described embodiments, but can be implemented with various modifications without departing from the scope of the invention.

[0038]

As is apparent from the above description, according to the method for treating refuse incinerated ash of the present invention, attention is paid to properties such as hydraulic property, light weight, water absorption, and basicity of the refuse incinerated ash. In addition, since the adjusted ash is generated from the refuse incineration ash and further the soil improvement material is generated, the refuse incineration ash can be effectively used at a low cost in an easy-to-handle and highly safe state. It has excellent practical effects.

Further, according to the soil improvement material of the present invention, waste incineration ash can be effectively produced at low cost, is easy to handle and has high safety, and can be used for various purposes. That is, it has an extremely excellent practical effect.

Claims (2)

[Claims] 1. After separating and removing metals from the refuse incinerator ash discharged from the refuse incinerator, coarse particles contained in the refuse incinerator ash are crushed to produce a conditioned ash as a whole. Then, a method for treating refuse incinerated ash is characterized in that a hydraulic substance is added to the adjusted ash to produce a soil improvement material. 2. A soil improvement material obtained by adding a hydraulic substance to adjusted ash, which is made into a granular form of refuse incineration ash from which metals have been separated and removed.