JP2002348573A - Greening and soil-stabilizing material having unsolubilizing property of heavy metals and engineering method for blowing seed to thick-layer substrate, method for stabilizing soil and method for treating polluted soil by each using the same material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a greening and soil-stabilizing material capable of rapidly aggregating and solidifying slurry add fertile soil and free from fear eluting heavy metals which are environmental pollution substances and provide an engineering method for blowing seeds to thick-layer substrate, an engineering method for stabilizing soil and a method for treating polluted soil by each using the material. SOLUTION: This greening and soil-stabilizing material having unsolubilizing property of heavy metals is obtained by mixing 100 pts.wt. ash component with 10-50 pts.wt. first additive composed of 1-20 wt.% aluminium sulfate, 1-20 wt.% calcium sulfate, 1-20 wt.% silica powder and 10-80 wt.% cement component and 0.2-10 pts.wt. second additive composed of 10-60 wt.% aluminium sulfate, 5-70 wt.% sodium thiosulfate and 5-50 wt.% iron powder.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a greening / soil stabilizing material having a performance of insolubilizing heavy metals, and a method of spraying a thick base material seed, a soil stabilizing method, and a contaminated soil using the same. Regarding the treatment method, more specifically, when used in the thick layer base seed spraying method, it exerts extremely excellent greening ability on sprayed surfaces such as slopes, and when applied to muddy soil, the muddy Soil can be solidified in a short time, and when used for contaminated soil, it is possible to suppress elution of environmental pollutants (heavy metals) in the soil and detoxify it. About the material.

[0002]

2. Description of the Related Art In order to protect slopes such as cliffs and to green the slopes, recently, a thick-layer base material seed spraying method has been widely applied. This thick-layer base seed spraying method is applied to soil, seeds, curing agents, fertilizers, soil conditioners, accelerators,
A mixture obtained by mixing a soil consolidating agent (glue) at a predetermined ratio is suspended in water to form slurry soil, and the obtained slurry soil is blown onto a slope provided with a lath net, for example. In addition, this method covers the slope with a sprayed surface having a desired thickness.

In the slurry soil sprayed on the slope, the above-mentioned sizing agent contained therein hardens with time, and in the process, the soil particles of the soil are adhered to each other to form soil particles. Agglomeration proceeds. Then, in the curing process of the glue and the agglomeration process of the soil particles, cracks are generated on the sprayed surface, and the added vegetation material germinates and grows from these cracks. However, the conventional slurry soil has a slow curing speed because the sizing agent for agglomerating the soil particles is mainly composed of a resin polymer, and therefore, the slurry soil sprayed on the slope is completely solidified. The time required to settle on the slope in a stable state becomes longer, and usually a curing time of about 2 to 3 days is required.

[0004] Therefore, if, for example, rain falls before the sprayed slurry soil solidifies after construction, the entire sprayed surface will run off. If that happens,
Since rebuilding is required at a later date, the overall construction cost increases significantly. Also, in the conventional slurry soil, since the sizing agent is mainly made of a resin polymer, when the sizing agent is completely cured, the surface of the aggregated soil is in a dry state, and has poor water retention and air permeability. As a whole, there is a problem that the germination state of the vegetation material is mottled and its germination rate is reduced. In particular, as the thickness of the sprayed surface increases, the amount of sizing agent to be mixed with the soil increases, so that the surface dryness described above further progresses, and the vegetation material becomes difficult to germinate.

[0005] In addition, it is difficult to form a thick sprayed surface in a single hour in the conventionally used slurry soil because the curing speed of the sizing agent is low. Depending on the region, only a spray surface with a thickness of about 1 cm can be formed in one day. Therefore, for example, thickness 3cm or 5cm
It takes a long construction time of about 3 to 5 days to form such a sprayed surface, and a longer construction time is required depending on the presence or absence of rain during this time.

[0006] In order to solve such a problem, a greening / soil stabilizing material mainly containing an ash component such as fly ash or incineration ash of papermaking sludge and containing no resin polymer, and a thick layer base material using the same. A seed spraying method and a soil stabilization method have been developed (see Patent No. 2935408). According to this prior art, after spraying, 1-3
After a lapse of time, agglomeration occurs and does not run off even with normal rainfall. A single spraying operation can form a spraying surface with a thickness of about 8 cm, and the formed spraying surface Is porous, rich in air permeability and water retention, it can germinate vegetation seeds at a high germination rate from the whole sprayed surface, it can be a soil that does not cause frost heave deterioration, and it can be muddy When used in combination with soil, the muddy soil can be solidified and stabilized in a single hour.

[0007] As a recent trend, regulations on environmental pollution such as soil pollution and water pollution have become very strict. For example, regarding soil contamination, the Environment Agency Notification No. 46, August 23, 1991 (hereinafter referred to as environmental standard)
Lists the types of contaminants, specifies their elution allowances, and informs them that they will strive to achieve and maintain the standards as soon as possible for soils that do not meet the environmental standards.

[0008] In view of the above, it is required to satisfy the above-mentioned environmental standards even in a place where a thick base material seed spraying method or a soil stabilization method is constructed using a greening / soil stabilizing material. Will be done. From this viewpoint, when examining the inorganic material of the aforementioned Japanese Patent No. 2935408, it is considered that the ash component, which is the main component, generally contains various pollutants (mainly heavy metals). After the construction, the contaminants may elute by, for example, rainwater, and cause environmental pollution at the construction site.

Therefore, the greening / soil stabilizing material used in the above-mentioned construction method, in addition to the above-described performance of rapid agglomeration and solidification, suppresses elution of environmental pollutants from the construction site. Therefore, it is also required to prevent environmental pollution as an important requirement. In addition, various heavy metals are also detected in the site of the factory or the sludge sediment. Then, in order to prepare and reuse the land, it is necessary to improve the soil so that heavy metals in the contaminated soil are not soluted and eluted.

[0010]

SUMMARY OF THE INVENTION The present invention relates to a revegetation and soil stabilization material developed to meet the above-mentioned demands, and to use the material for spraying a thick-layer base material seed or a soil stabilization method. When it is performed, it is firmly fixed to the ground surface, and a construction surface having excellent air permeability and water retention can be formed in a short time, and at the same time, when used for treatment of contaminated soil, for example, copper contained in the soil is To provide revegetation and soil stabilization materials with insolubility of heavy metals, which can insolubilize heavy metals represented by chromium, lead, hexavalent chromium, etc. and detoxify the contaminated soil And It is another object of the present invention to provide a method for spraying a thick base material seed, a method for stabilizing soil, a method for treating contaminated soil, and a method for detoxifying ash and cement components using the material.

[0011]

In order to achieve the above-mentioned object, in the present invention, 10 to 50 parts by mass of a first additive containing at least calcium sulfate and a cement component, and 100 parts by mass of an ash component; And 0.2 to 10 parts by mass of a second additive containing aluminum sulfate, sodium thiosulfate, and a reducing material containing iron as a main component. The present invention provides a greening / soil stabilizing material having properties (hereinafter, referred to as the material of the present invention).

Preferably, for 100 parts by mass of the ash component,
Aluminum sulfate 1-20% by mass, calcium sulfate 1
1st additive 10-50 which consists of 20 mass%, silica powder 1-20 mass%, and cement component 10-80 mass%
0.2 to 10 parts by mass of a second additive consisting of 10 to 60% by mass of aluminum sulfate, 5 to 70% by mass of sodium thiosulfate, and 5 to 50% by mass of a reducing material containing iron as a main component The present invention provides a greening / soil stabilizing material having insolubilizing properties of heavy metals, which is obtained by mixing

In the above-mentioned material of the present invention, iron powder can be used as the reducing material. In the present invention, the soil, the material of the present invention, vegetative seeds or plant rhizomes, and water to prepare a slurry-like soil,
Thick base material seed spraying method characterized by spraying the guest soil on the ground surface, muddy soil, soil stabilization method characterized by mixing and stirring the material of the present invention, contaminated soil, Mixing and stirring the material of the present invention to insolubilize heavy metals in the contaminated soil, a method for treating contaminated soil, furthermore, an ash component and at least the second additive described above. Mixing and stirring, a method of treating an ash component characterized by insolubilizing heavy metals in the ash component, a cement component, and mixing and stirring at least the second additive described above, There is provided a method for treating a cement component, which comprises insolubilizing heavy metals in the cement component.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The material of the present invention is prepared by mixing an ash component and first and second additives described below. When the material of the present invention is dispersed in water to form a slurry,
The slurry exhibits thixotropic properties. That is, when the slurry is agitated and stressed in the tank, good fluidity is exhibited, but, for example, when sprayed on a slope, fluidity is lost at the moment of contact with the slope, and It has the property of adhering to the slope. The addition of the second additive described below provides a function of suppressing elution of environmental pollutants such as heavy metals.

First, as ash components, SiO ₂ , Al ₂ O
₃ , a powder of a hydraulic substance containing a CaO as a main component and having hydration activity and reacting with water to convert to a hydrate is used. Specifically, for example,
Examples include fly ash, paper sludge incineration ash, and blast furnace slag. Among them, fly ash specified in JIS A6201 is suitable as fly ash because it is easily available and can reduce material costs. Incineration ash of paper sludge is chlorine-based bleaching in the paper making process. The incineration ash of the papermaking sludge obtained without using an agent contains an MgO component.
Is preferable because the leaves and foliage of the vegetation that germinates and grows from the spraying surface become green.

The ash component disperses colloidally in water at the time of preparing the slurry, and at the same time, causes a hydration reaction with coexisting water. At least a surface portion of the ash component such as ettringite or calcium silicate hydrate is formed. It rapidly converts to mineral hydrate and hardens. If the soil coexists in this slurry, the hydrated compound of the above-mentioned minerals is generated in a state in which the soil particles themselves are scattered, so that, eventually, a large number of soil particles and the hydrated compound Are formed into porous aggregates having a composite structure. Then, in the process of forming the above-mentioned porous aggregates, the moisture in the soil is rapidly absorbed by the porous aggregates, and the hardening of the ash component itself progresses.

Therefore, unlike the conventional aggregated state in which the soil particles are adhered to each other with the sizing agent, the formed aggregates are porous and absorb the moisture in the soil there. As a result, the air permeability and water retention are good, and the elasticity is high. Next, the first additive contains at least a cement component and calcium sulfate as essential components. Further, it preferably contains aluminum sulfate and silica powder.

When the prepared slurry soil is sprayed on, for example, a slope, the cement component is incorporated in order to agglomerate the slurry soil in a short time and to secure the strength of the sprayed surface. The cement component is not particularly limited, and for example, Portland cement and early-strength cement used as a construction material for emergency construction are suitable. The ratio of the cement component is preferably set to 10 to 80% by mass based on the total amount of the first additive. If this ratio is less than 10% by mass, the above-mentioned effects are not sufficiently exerted. Conversely, if the ratio is more than 80% by mass, the setting of the slurry after the application excessively proceeds, resulting in a very hard construction surface, This is because, for example, when a vegetation material is added, the germination and growth of the vegetation material are hindered.

Calcium sulfate dissolves and dissociates in water when a slurry is prepared, causes aggregation of ash components, and reacts with ash components to form ettringite and silicate, similarly to aluminum sulfate described later. Produces calcium hydrate. It is preferable that the ratio of the calcium sulfate is set to 1 to 20% by mass based on the total amount of the first additive. When this ratio is less than 1% by mass, the above-mentioned effects are not sufficiently exerted. On the contrary, when the ratio is more than 20% by mass, the calcium sulfate itself is a gypsum component, so that the prepared slurry starts to be plastered. This is because it becomes hard and it becomes difficult to perform spraying construction.

Next, aluminum sulfate disperses the material of the present invention in water to form a slurry, which dissolves in water to function as an electrolyte, and forms ettringite with the ash component dispersed in colloidal form. Produces and promotes its aggregation. When soil coexists, polycondensation ions of aluminum are formed as a polymer in the process of forming aluminum hydroxide through hydrolysis, and this condenses while spreading the soil particles.

The proportion of the aluminum sulfate is preferably set to 1 to 20% by mass based on the total amount of the first additive. When this ratio is less than 1% by mass, the effect of coagulating ash components and the effect of forming ettringite are reduced, so that rapid stabilization of the soil and absorption of moisture in the soil cannot be achieved, and conversely, 20% by mass. Even if the amount is increased, the compounding effect only reaches saturation and the cost increases.

This aluminum sulfate is also an essential component of the second additive described later, and is supplied from the second additive when the first additive and the second additive are mixed with the ash component. , May not be included in the first additive. When the material of the present invention is aggregated and solidified, the silica powder is dispersed in the aggregates and contributes to maintaining strength. The silica powder used is not particularly limited, for example,
Fumed silica, natural shirasu, and the like can be given as preferable examples. In particular, since fumed silica is amorphous, it is useful because it can be combined with an ash component and a cement component described later to increase the strength of aggregates while vigorously crystallizing simultaneously with the preparation of the slurry.

The ratio of the silica powder is preferably set to 1 to 20% by mass based on the total amount of the first additive. If this ratio is less than 1% by mass, the above-mentioned strength improving effect is not sufficiently exerted. Conversely, if it is more than 20% by mass, the compounding effect reaches saturation and the cost increases. . The first additive is mixed in an amount of 10 to 50 parts by mass with respect to 100 parts by mass of the ash component.

If the mixing ratio of the first additive is less than 10 parts by mass, rapid aggregation and solidification of the prepared slurry does not proceed. If it is more than 50 parts by mass, the cement component relatively increases. Therefore, the construction surface and construction soil become excessively hard. In any case, it is unsatisfactory as a greening spray material or a stabilizing material for muddy soil, in which the vegetation material does not run off from the rainwater, does not cause frost heave deterioration, and germinates and grows evenly from the sprayed surface.

Next, the second additive will be described. This second additive contains, as essential components, a reducing material mainly composed of aluminum sulfate, sodium thiosulfate, and iron. Aluminum sulfate in the second additive also
The same effect as aluminum sulfate as the first additive is exerted, but considering that the second additive realizes the insolubilization of heavy metals, the above-mentioned polycondensation of aluminum is considered. In the process of condensing while incorporating soil particles with the formation of ionic macromolecules, heavy metals are also incorporated and condensed at the same time, so this heavy metal is not taken up and insolubilized. It is thought.

The proportion of this aluminum sulfate is preferably set to 10 to 60% by mass based on the total amount of the second additive. If this proportion is less than 10% by mass, the effect of insolubilizing the heavy metals described above decreases, and if it exceeds 60% by mass, the effect reaches saturation and the cost increases. Next, sodium thiosulfate exhibits a dechlorination effect, for example, PCB, dichloromethane, carbon tetrachloride, 1,2-dichloroethane, 1,1-dichloroethylene, cis-1,2-dichloroethylene, 1,1,1-trichloroethane. Of chlorine-containing pollutants such as 1,1,1,2-trichloroethane, trichloroethylene, tetrachloroethylene, 1,3-dichloropropene (detoxification)
Contribute to. In addition, sodium thiosulfate is decomposed into components of Na, S, and O _{2 in} the coexistence of water, and these components are combined with heavy metals alone or in combination with each other. The heavy metals are insolubilized (detoxified) by forming a strong sulfide or the like.

If the amount of the sodium thiosulfate in the second additive is too small, the above-mentioned effects are not sufficiently exerted. On the other hand, if the amount is too large, the relative amounts of the above-mentioned aluminum sulfate and the below-mentioned reducing material are reduced. The amount is reduced so that the manifestation of their effects is diminished. For this reason, the blending amount of sodium thiosulfate is set to 5 to 70% by mass based on the total amount of the second additive.

The reducing material containing iron as a main component reduces heavy metals and, at the same time, combines with heavy metals by the catalytic action of sodium thiosulfate to insolubilize them. In particular, when the heavy metal is a hexavalent chromium component, it converts it into a stable and harmless compound such as chromium oxide. As such a reducing material, for example, iron powder is preferable in that it is inexpensive, easily available, and has a large reducing effect.

As such iron powder, for example, RDL-
300 (trade name, manufactured by Powdertech Co., Ltd.) and the like. If the amount of the reducing material containing iron as a main component is too small, the above-mentioned effects are not sufficiently exhibited,
Conversely, if it is too large, the relative amounts of the other essential components decrease, and the manifestation of the effects of these components is reduced, so that the compounding amount is 5 to 50 mass% based on the total amount of the second additive. Set to%.

The second additive is composed essentially of the above-mentioned three components, but depending on the type and amount of heavy metals,
The following materials may be further blended. For example, PC
For the insolubilization of B, cadmium, and dioxin, it is preferable to mix zeolite and pineapple enzymes. For fluorine, boron, etc., it is preferable to mix activated carbon, silica gel, quicklime, and zeolite. it can.

The second additive is mixed in an amount of 0.2 to 10 parts by mass with respect to 100 parts by mass of the ash component. If the mixing amount of the second additive is less than 0.2 parts by mass, the insolubilization of heavy metals cannot be sufficiently realized, and if the mixing amount is more than 10 parts by mass, the relative amount of the first additive will be increased. This is because rapid aggregation and solidification of the slurry do not proceed.

As such a second additive, for example, Alpha Green (trade name, manufactured by Alpha Green)
Is preferred. It is preferable to further mix a ceramic powder with this material. This ceramic powder,
Although the ceramic powder itself is not involved in the hydration reaction or the formation of porous aggregates, since these ceramic powders are aggregates of porous particles, they are dispersed in the formed aggregates to form the aggregates. To increase the water permeability and water retention of the seeds, and also enhance the seed vigor. Furthermore, it plays a role in ensuring the long-term effectiveness of the fertilizer added to the soil and creating an extremely favorable environment for growing vegetation. In addition, since the above-mentioned effects are exhibited even with a very small amount of compounding, it contributes to cost reduction of products.

The ceramic powder is not particularly limited, but for example, FB material (trade name) manufactured by Filton International Co., Ltd. is suitable. The mixing amount of the ceramic powder is set to 10 parts by mass or less based on 100 parts by mass of the ash component. If the amount is more than 10 parts by mass, rapid aggregation and solidification of the slurry after application is difficult to occur, the strength of the aggregate itself starts to decrease, and the cost is increased.

The above-mentioned material of the present invention is used as follows. First, it is used for the thick layer substrate seed spraying method. That is, water, soil, seeds, a nutrient, a fertilizer, a soil conditioner, a promoter, and the like are charged into a tank having a predetermined volume, and the mixture is stirred, and the material of the present invention is further charged therein. At this time, the amount of injected water and the amount of soil are appropriately adjusted so as to have a viscosity suitable for spraying construction. Then, the whole is sufficiently agitated to obtain spray slurry.

The obtained slurry soil is sprayed on a predetermined ground surface, for example, a slope, and adhered to the surface, thereby completing the construction. At the same time as spraying, the soil loses fluidity and adheres firmly to the ground surface,
In addition, the agglomeration of the soil rapidly progresses and the whole solidifies with elasticity. Further, since the elution of the pollutants (heavy metals) contained in the ash component, the cement component, and the like is suppressed by the action of the second additive, environmental pollution after construction is prevented.

Next, it is used for a method of stabilizing muddy soil. The target muddy soil and a predetermined amount of the material of the present invention may be mixed, stirred, and compacted. Due to the hydration reaction of the material, the water in the muddy soil is quickly absorbed and
Solidification progresses to increase the strength. As a result, the muddy soil is stabilized in a short time.

For the treatment of the contaminated soil, the contaminated soil and a predetermined amount of the material of the present invention may be mixed and stirred. At this time, it is preferable to uniformly mix and stir so as to minimize mixing unevenness so as to effectively exert the insolubilizing effect of the heavy metals included in the material of the present invention. The second additive of the material of the present invention itself can be used as an agent for realizing insolubilization of heavy metals.

For example, by mixing and stirring the ash component and the second additive, heavy metals in the ash component can be insolubilized, and by mixing and stirring with the cement component, Heavy metals can be insolubilized.

[0039]

[Embodiment 1] Production of the greening / soil stabilizing material of the present invention (1) Preparation of first additive 2% by mass of aluminum sulfate (manufactured by Sumitomo Chemical Co., Ltd.) and 2 mass% of calcium sulfate (manufactured by Noritake Co., Ltd.) %, 2% by mass of fumed silica (manufactured by Union Co.) and 13% by mass of fast-strength cement (manufactured by Tokuyama Co., Ltd.) to prepare a first additive.

(2) Second additive: 28.6% by mass of aluminum sulfate, 42.8% by mass of sodium thiosulfate, and 28.6% by mass of iron powder (RDL-300, manufactured by Powdertech Co., Ltd.) The second additive A was prepared by mixing. (3) Analysis of fly ash Fly ash was selected as an ash component, and the fly ash was subjected to a dissolution test prescribed by the Environment Agency Notification No. 46, and the obtained test solution was analyzed as shown in Tables 1 to 3. The contaminants were quantified by the method. The results are shown in Tables 1 to 3.

(4) Production of greening / soil stabilizing material and analysis of pollutants 37.9 parts by mass of the first additive and 2.5 parts by mass of the second additive A were mixed with 100 parts by mass of the fly ash described above. Thus, a greening / soil stabilizing material of the present invention was produced. For comparison, the first additive 4 was added to 100 parts by mass of fly ash.
0.4 parts by weight of the mixed material, that is, the second additive A
Was manufactured without mixing.

The obtained material was subjected to the same dissolution test as in (3) to prepare a test solution, and the amount of contaminants was determined. The results are shown in Tables 1 to 3.

[0043]

[Table 1]

[0044]

[Table 2]

[0045]

[Table 3]

As apparent from Tables 1 to 3, despite the use of fly ash in which various environmental pollutants elute above the environmental standard value, any of the contaminants eluted from the material of the present invention are Are below environmental standards. And in the case of the material of the comparative example which does not contain the second additive A, some pollutants exceed the environmental standard value.
For these reasons, the effect of blending the second additive A is obvious.

(5) Implementation of the Thick Layer Substrate Seed Spraying Method Into the tank, water, soil, seeds, a curing agent, and a fertilizer are charged and stirred, and the materials of Example 1 and the comparative example are further charged. Thereafter, the mixture was stirred to prepare two types of slurry soil. The slurry soil was sprayed on a slope having an inclination of about 30 ° and an area of about 80 m ² . The construction work was carried out in the middle of light rain on the way, but the good clinging to the slope due to the agglomeration effect and the immediate effect were exhibited, and neither of the two types of soil was washed away Work has been completed.

After the completion of the construction work, there was considerable rainfall from midnight, but on the next day, the sprayed surface was observed. For comparison, construction using conventional slurry soil was also performed, but on the sprayed surface, the soil was washed away and the lath net was completely exposed. Observation of the sprayed surface four weeks after the construction showed that the sprouted seeds were evenly germinated from the sprayed surface and that the soil was in the same state as at the time of spraying. However, conventionally, the sprayed surface of the soil was germination from cracks, and the germination state was mottled.

When the sprayed surface was observed after a lapse of one winter, the grown leaves were dense and there was no loss of soil.
The condition was the same as when spraying. Thus, good results can be obtained as a thick base material seed spraying method using either the material of the example or the material of the comparative example.
However, the use of the example materials is useful in terms of environmental conservation because elution of environmental pollutants from fly ash is suppressed.

Example 2 Cadmium eluted from a certain field soil was determined by applying a dissolution test according to No. 47 of 1976 and a flame atomic absorption method specified in JIS K010255.2. Cadmium analysis value was 3.6 mg / kg. Then this field soil 1
To 100 parts by weight, 10 parts by weight of the material used in Example 1 was mixed, and the mixture was subjected to the above-mentioned test to analyze the leached cadmium. The result was 0.01 mg / kg.

As is apparent from the above, the material of the present invention effectively prevents the elution of cadmium. Example 3 Ordinary Portland Cement, Early Portland Cement, and Blast Furnace Cement Notification of the Environment Agency No. 46: Hei 10
Based on Announcement 21, JIS K0102 65.2.3
The elution amount of hexavalent chromium was quantified by applying the electric heating atomic absorption method specified in (1).

Then, for 100 parts by mass of each cement,
2 parts by mass of the second additive A was mixed and stirred, and the obtained mixture was subjected to the above test to analyze the elution amount of hexavalent chromium. Table 4 shows the results.

[0053]

[Table 4]

As is clear from Table 4, the second additive A insolubles hexavalent chromium in the cement to effectively prevent its elution. Example 4 With respect to coal ash (fly ash) as a by-product of a thermal power plant, the elution amount of heavy metals was measured based on Environment Agency Notification No. 46: Hei 10 Announcement 21.

Next, with respect to 100 parts by mass of the coal ash,
Six parts by mass of the second additive A was blended, mixed and stirred, and the above mixture was subjected to the above test to analyze the elution amount of heavy metals. Table 5 shows the results.

[0056]

[Table 5]

[0057]

As is apparent from the above description, the greening / soil stabilizing material of the present invention does not run off by ordinary rainfall after about one hour has elapsed after spraying. In addition, if the inclined surface is a normal inclined surface of about 35 °, it is possible to spray the thick-layer base material seed without using a lath net or a net. Furthermore, since frost heave deterioration does not occur, greening can be sprayed in a cold region.

In addition, muddy soil can be solidified and stabilized in a short time. Furthermore,
Since the material of the present invention has the insolubilizing property of heavy metals, when mixed with contaminated soil and used, the pollutants (heavy metals) contained in the soil are insolubilized to prevent elution thereof. Therefore, its industrial value is extremely great for preventing the spread of pollution and protecting the environment.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) C09K 17/06 E02D 17/20 102F 17/08 C09K 101: 00 17/10 B09B 3/00 304K E02D 17/20 102 ZAB // C09K 101: 00 F term (reference) 2B022 AB02 BA01 BA04 BA07 BA14 BB10 DA19 2D044 DA33 4D004 AA41 AB03 AB06 CA15 CA37 CC09 CC11 CC13 DA03 DA10 4H026 AA01 AA02 AA15 AB02 AB03

Claims (12)

[Claims] A first additive containing at least calcium sulfate and a cement component based on 100 parts by mass of an ash component.
50 parts by mass, and a second material containing aluminum sulfate, sodium thiosulfate, and a reducing material mainly containing iron.
A revegetation / soil stabilization material having heavy metal insolubilizing properties, which is obtained by mixing 0.2 to 10 parts by mass of an additive. 2. 100 parts by mass of the ash component, 1 to 20% by mass of aluminum sulfate, 1 to 20% by mass of calcium sulfate, 1 to 20% by mass of silica powder, and 1 part of cement component
10 to 50 parts by mass of a first additive consisting of 0 to 80% by mass,
And a second additive of 10 to 60% by mass of aluminum sulfate, 5 to 70% by mass of sodium thiosulfate, and 5 to 50% by mass of a reducing material containing iron as a main component.
The greening / soil stabilizing material having insolubility of heavy metals according to claim 1, which is obtained by mixing 10 parts by mass. 3. The method according to claim 2, wherein 10 parts by mass or less of the ceramic powder is mixed with 100 parts by mass of the ash component.
Greening and soil stabilizing material with insolubility of heavy metals. 4. The method according to claim 1, wherein the reducing material is iron powder.
3. A greening / soil stabilizing material having insolubility of any of the heavy metals according to item 3. 5. The iron powder is RDL-300 (trade name,
5. The greening / soil stabilizing material having insolubility of heavy metals according to claim 4, which is manufactured by Powder Tech Co., Ltd.). 6. The greening / soil stabilizing material according to claim 2, wherein the silica powder is fumed silica. 7. The greening / soil stabilizing material having insolubilizing properties of heavy metals according to claim 1, wherein the ash component is fly ash or incineration ash of papermaking sludge. 8. A slurry-like soil is prepared by mixing soil, the material according to any one of claims 1 to 7, vegetation seeds or plant rhizomes, and water, and spraying the soil onto the ground surface. A thick layer base material seed spraying method characterized by the above-mentioned. 9. A method for stabilizing a soil, comprising mixing and stirring muddy soil and the material according to claim 1. 10. A method for treating contaminated soil, comprising mixing and stirring the contaminated soil and the material according to claim 1 to insolubilize heavy metals in the contaminated soil. . 11. An ash component wherein the ash component and at least the second additive according to claim 1 or 2 are mixed and stirred to insolubilize heavy metals in the ash component. Processing method. 12. A cement component and at least 1
Or mixing and stirring with the second additive according to 2,
A method for treating a cement component, comprising insolubilizing heavy metals in the cement component.