JPH0481493A - Soil improving agent - Google Patents

Abstract

PURPOSE:To obtain a soil improving agent, capable of readily providing soil excellent in water draining properties at a low cost simply by adding thereof in a small amount to the soil and useful for tennis courts, playgrounds, golf links, etc., by blending a paramagnetic substance with an aluminum-based compound. CONSTITUTION:The objective improving agent is obtained by blending preferably 1-20wt.% paramagnetic substance [e.g. ferrite (MO.Fe2O3) (M is bivalent metal and Fe, Mn or Zn) or iron oxyhydroxide (gamma-FeOOH), etc.] with preferably 80-99wt.% aluminum-based compound [e.g. boehmite-based alumina (gamma-Al2O3), etc.] and preferably calcium phosphate-based compound {e.g. apatite [Ca10(PO4)6(OH.F)2], etc.}.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a soil conditioner that is added to soils that require good drainage, such as tennis courts, athletic fields, and golf courses.

[Prior Art] When constructing various outdoor sites such as tennis courts, athletic fields, and golf courses, it is always required to have good drainage.

Traditionally, the method of improving drainage has been to dig up the site, lay a gravel layer on the bottom layer, and create a surface layer with less clay (
The main method used was to lay down soil with a lot of fine sand and tamp it down.

Further, JP-A-63-54936 discloses an active material in which a divalent and trivalent iron salt is dispersed and supported on an alumina hydrate.

[Problems to be Solved by the Invention] However, the above-mentioned method has the problem that it requires extremely detailed and laborious civil engineering work, which takes an enormous amount of money and time.

Furthermore, the active material disclosed in JP-A-63-54936 is intended for deodorization, antibacterial and biological activation, and there is no suggestion that it can be used as a soil conditioner. .

The purpose of the present invention is to create an outdoor site with good drainage by eliminating the need for the extremely large-scale civil engineering work that was previously required, and by simply adding a small amount to ordinary soil. An object of the present invention is to provide a soil conditioner that can obtain soil with good drainage at a low cost.

[Means for Solving the Problems] As a result of intensive studies to solve the above problems, the inventors have arrived at the present invention.

That is, the gist of the first aspect of the present invention is a soil conditioner containing a paramagnetic substance and an aluminum compound.

Moreover, the gist of the second invention is a soil conditioner comprising a paramagnetic substance, an aluminum compound, and a calcium phosphate compound.

Next, the present invention will be explained in detail.

First, the soil conditioner of the first invention will be explained.

The paramagnetic substance used in the present invention includes ferrite [MO-Fe203] (M is a divalent metal, Fe,
Indicates Mn and Zn. ), iron oxyhydroxide (e.g. near-Fe
OOH, δ-Fe00H), maghemite (γ-Fe
20. :+), and the particle size is preferably 100 μm or less. Paramagnetic substances are positively charged [for example, ferrite is +0. 66 (in Xe)] and shows a coagulating effect on clay. It also exhibits a so-called magnetic effect, which increases the flow of water due to magnetism.

In addition, as the aluminum-based compound, boehmite alumina (γ-AI.03) is mainly mentioned, and the length is 1
It is desirable that the particles are fibrous ultrafine particles of 0 μm or less,
The boehmite alumina alone forms an alumina hydrate sol. Like the paramagnetic substance, this aluminum-based compound is positively charged and exhibits a high coagulation effect on clay. It also has the function of dispersing and supporting paramagnetic substances to prevent agglomeration.

The blending ratio of the two components in the first invention is preferably 1 to 20% by weight of the paramagnetic material and 80 to 99% by weight of the aluminum compound. If the proportion of the paramagnetic substance is less than 1% by weight, the effect of improving the drainage properties of the soil of the present invention may not be sufficiently exhibited, and if it exceeds 20% by weight, the above-mentioned drainage properties may not be exhibited. Not only that, but
This is both undesirable as it increases the cost.

The soil conditioner of the first invention is prepared, for example, as follows. A mixed powder obtained by drying a coprecipitated sol of a paramagnetic substance and an aluminum compound, which are blended in advance in the above ratio, is prepared, and an inorganic binder (for example, phosphoric acid,
Approximately 2 parts by weight of a dilute aqueous solution (1 to 2%) of aluminum phosphate, acidic magnesium phosphate, etc.) is added to 100 parts by weight of the mixed powder to form a raw material. This has a moisture content of 3%
Pressure molding into an appropriate shape (pressure 30-100kg/
After cTl), it is heated in a heating furnace at 300° C. or less for about 1 hour to obtain a hardened product, which is then crushed (40 to 400 meshes) to obtain a powder.

Next, regarding the soil conditioner of the second invention, mainly the differences from the first invention will be explained.

In addition to the above-mentioned paramagnetic substance and aluminum compound, the components used in the present invention include a calcium phosphate compound. This calcium phosphate compound includes phosphate apatite [Ca1O
(P 04)6(OH-F )2], tricalcium phosphate [Ca3(PO2)2] calcium hydrogen phosphate (
CaHPO+) and the like. These calcium phosphate compounds slightly dissolve 20 to 200 ppm/hour of Ca2+ per gram and, like the two components above, have a coagulant effect on clay, but are further activated by the magnetic action of paramagnetic substances to coagulate water. Shows cationic action with increased attraction of molecules.

In the present invention, the calcium phosphate compound itself is slightly soluble in Ca2+, and the compound produced by reaction with other components in an aqueous solution hardens in the drying process, that is, 3
Heating at relatively low temperatures, up to 00°C, further increases the bond strength, making it possible to bond without impairing the functionality of each component, thus eliminating the need to add separate binders during preparation. .

In the second invention, the blending ratio of each component is 50 to 100 parts by weight of the calcium phosphate compound to 100 parts by weight of the two components (paramagnetic substance + aluminum compound) having the blending ratio described above in the first invention. It is desirable to do so. If the blending ratio of the calcium phosphate compound is out of the above range, the effect of the present invention for improving soil drainage may not be fully exhibited, which is not preferable.

The soil conditioner of the second invention is prepared, for example, as follows. A slurry of calcium phosphate compound (20
Fine powder of calcium phosphate compound of 0 mesh or less 5
~20% by weight, the remainder consisting of an aqueous phosphoric acid solution with a concentration of 2% or less) is added and blended to form a raw material. This is obtained by pressure-molding it by the same method as described above, heating it, and then crushing it to form a powder.

In addition, a method of obtaining a mixed sol by co-precipitation of a basic aluminum salt (aluminum chloride, aluminum sulfate, aluminum nitrate, etc.) and an iron salt solution and mixing it with a calcium phosphate compound may also be adopted.

The soil to which the soil conditioner of the present invention is applied is not particularly limited and may be any type of soil, but soils with high dry density, hardness, and conventionally considered to have poor drainage are preferred. This allows the effects of the present invention to be more fully exhibited.

In addition, methods for adding the soil conditioner of the present invention to soil include a method of mixing the soil conditioner and the soil, a method of spraying the soil conditioner to the soil, etc., but the latter method only involves spraying. This method can be said to be a more preferable method because the drainage effect of the present invention can be sufficiently exhibited and labor can be further saved.

Furthermore, the addition ratio of the soil conditioner of the present invention to the soil is as follows:
Although not particularly limited, it is preferably about 0.5 to 1 part by weight per 100 parts by weight of soil. 06
If the amount is less than 5 parts by weight, the drainage effect of the present invention may not be fully exhibited, and even if it is added in an amount exceeding 1 part by weight, the drainage effect will reach its limit, resulting in a cost increase. It becomes a waste of money.

[Function] In the first invention, the amount of water flowing through the soil to which the soil conditioner has been added increases due to the magnetism of the paramagnetic substance. Further, the paramagnetic substance and the aluminum compound are positively charged, and exhibit a coagulating effect on the aggregate of clay particle eternal spheres in the soil that has formed a thick water film. In other words, it neutralizes the negative charge of the negatively charged clay particles, significantly reduces the attraction of water molecules due to hydrogen bonds with the clay particles, and improves the fluidity of water. Furthermore, the aluminum-based compound imparts an alkaline substance to the paramagnetic substance to prevent deterioration, and disperses and supports the paramagnetic substance to prevent agglomeration.

Furthermore, in the second invention, in addition to the effects of the two components described above, the addition of a calcium phosphate compound further increases the coagulation effect. Furthermore, the compound produced in the aqueous solution reaction exhibits a curing effect during the drying process, increasing the bond strength with the other two components.

[Examples] Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Two types of soil were prepared:

Soil for raw material ■ (Kiso sand for Metsuchi): Approximately 15% clay,
79% sand (particle size, 47% less than 0.5μm, 0.5μm
m or more and less than 1.0 μm 45.5%, 1.0 μm or more7.
5%), moisture approximately 6% Soil for raw material ■: Clay content approximately 18%, sand content 76% (particle size 0
．． Less than 5 μm 46%, 0.5 μm or more and less than 1.0 μm 4
8.3%, 1.0 μm or more 5.7%), water content approximately 6% The following two types of soil conditioners were prepared.

Sample A (2 components), maghemite (7-Fe2o3) 1
0%, boehmite (γ-A1203) 89%, binder (
(Aluminum phosphate) 1% (Processing method) The above composition was heated to 30-5% at a moisture content of 2.5%.
The pieces were pressurized at a pressure of 0 kg/ct, cut into 1 cm square pieces, fired at 3008C for 1 hour, and then crushed.
It was made into a powder of less than mesh size.

Sample B (3 components): ferrite (Fe30<)s%,
Boehmite 45%, tricalcium phosphate [Ca3(PO
*)] 5o% (Processing method) Tricalcium phosphate (200 mesh or less)
A slurry is prepared in advance using a phosphoric acid solution (concentration 2%) containing 20% solid content.

After adding the slurry to the ferrite and boehmite powder and mixing thoroughly so that it has the above composition in terms of solid matter, dry it.
It was dried, fired, and crushed in the same manner as Sample A at a moisture content of 2.5% to obtain a powder of 80 mesh or less.

Sample soil: 1 part by weight of the sample A or Bo was mixed with 100 parts by weight of the raw material soil I or 1 to obtain treated soil, and for comparison, the soil without sample addition was used as untreated soil. .

Next, using a device conforming to JIS A-1218, a water permeation sampler (100cc) was installed at the bottom of the mold.
After filling the sample soil, it was tamped 25 times with a stamp to create four types of samples with different dry densities (indicating the degree of tamping).

After each sample was saturated with water for 24 hours, the hydraulic conductivity was measured by the constant water level method.

The results obtained are shown in Tables 1 to 3.

However, the hydraulic conductivity K"UT" L "Q/U+s・h・
A-t (A: sample cross-sectional area 19.6 cnr, L: sample length 5.0 mark, h: water level difference 7.0 cm, t: measurement time (
time), Q: water permeability (cc), viscosity coefficient of water at UT/T°C) In addition, the unit of dry density in Tables 1 to 3 is g/C-, and the unit of permeability coefficient is mm/ This is the value converted into time.

As is clear from Table 1, Table 2, Table 3, and Table 1, it can be seen that the soil containing the soil conditioner of the present invention has improved drainage performance in both soils I and II. Comparison of Examples 1 to 4 and Comparative Examples 1 to 4, Comparison of Examples 4 to 8 and Comparative Examples 1 to 4, Comparison of Examples 9 to 12 and Comparative Examples 5 to 8, Example 13
-16 and Comparative Examples 15-8).

In addition, it exhibits an excellent effect on soils with a high dry density, that is, hard soils that conventionally had poor drainage, with a dry density of 1.
It can be seen that when the hardness is 4 or more, the drainage performance is improved by about twice or more (Comparison of Examples 3 and 4 and Comparative Examples 3 and 4, Examples 7 and 8 and Comparative Example 3, 4, Comparison of Example 4.12 and Comparative Examples 7 and 8, Comparison of Example 15.16 and Comparative Examples 7 and 8).

Furthermore, the soil containing sample B (three components) was better than that of sample A.
It can be seen that compared to the soil containing (two components), the drainage properties are improved in both cases (Comparison of Examples 1 to 4 and Examples 5 to 8, Examples 9 to 12 and Examples 13 to 16).

In addition, in the soil conditioner of the present invention, each component is strongly bonded to each other and is slightly soluble, so drainage properties are maintained over a long period of time, and each component is harmless to humans and animals.
It has the advantage of not polluting the environment.

[Effects of the Invention] The soil conditioner of the first aspect of the present invention can be easily added to soil in a small amount, and soil with good drainage can be obtained at low cost, eliminating the need for large-scale construction that was previously required. This has the effect of making civil engineering work completely unnecessary.

In addition, the soil conditioner of the second invention provides the effects of the first invention, particularly improved drainage performance.

Patent applicant Panyo Scientific Co., Ltd. Agent
Patent attorney On 1) Joint office (1 other person)

Claims (1)

[Claims] 1. A soil conditioner containing a paramagnetic substance and an aluminum compound. 2. A soil conditioner containing a paramagnetic substance, an aluminum compound, and a calcium phosphate compound.