KR101937980B1 - Composition for preparing soil conditioner, soil conditioner and method of conditioning soil using the soil conditioner - Google Patents

Abstract

A composition for preparing a soil conditioner, a soil conditioner and a method for conditioning soil are disclosed. The disclosed soil conditioner comprises 100 parts by weight of bauxite residues, 5 to 15 parts by weight of a solidifying agent, 5 to 25 parts by weight of a thickener, 7.5 to 10 parts by weight of water and 1 to 10 parts by weight of a fertilizer component. One embodiment of the present invention provides the composition for preparing the soil conditioner, which is capable of modifying acidic soil to soil having a pH in the range of 6.0 to 8.0.

Description

TECHNICAL FIELD The present invention relates to a composition for preparing a soil conditioner, a soil conditioner and a soil conditioner,

A composition for the preparation of a soil conditioner, a soil conditioner and a soil improvement method are disclosed. More particularly, the present invention discloses a composition for preparing a soil conditioner, a soil conditioner and a soil conditioner, which can improve an acidic soil to a soil having a pH ranging from 6.0 to 8.0.

In general, soil in Korea is composed of granite and granitic gneiss, more than 50% of which is acidified due to soil loss caused by heavy rain in summer and potassium leaching and excessive use of chemical fertilizer. It is going.

Furthermore, recently, the frequency of acid rain has been increased, so acidification of the soil has been accelerated, resulting in a significant decrease in agricultural productivity and forest tree growth.

In order to neutralize the acidified soil, calcium carbonate (CaCO ₃ ) or calcium hydroxide (CaO) is conventionally used in the past. However, excessive use of such lime may cause the ratio of magnesium (Mg) to potassium Resulting in magnesium (Mg) deficiency.

In particular, these chemical treatment methods can neutralize acidified soils, but generate heat when contacted with moisture, and significantly reduce useful microorganisms having the ability to purify natural soils, resulting in natural soil cleansing ability But also breaks the physical and chemical balance of the soil, thereby deteriorating the regeneration ability of the soil, thereby damaging crops.
BACKGROUND ART [0002] Techniques of the background of the present invention are disclosed in Korean Patent Laid-Open Nos. 10-2015-0037175 (2015.04.08.), Japanese Patent Application Laid-Open No. 2010-163619 (2010.07.29.) And Korean Registered Patent No. 10-1720958 (Mar. 29, 2017).

One embodiment of the present invention provides a composition for the preparation of a soil conditioner which is capable of improving an acidic soil to a soil having a pH in the range of 6.0 to 8.0.

Another embodiment of the present invention provides a soil conditioner prepared from the composition for preparing the soil conditioner.

Another embodiment of the present invention provides a soil improvement method using the soil amendment agent.

According to an aspect of the present invention,

100 parts by weight of bauxite residue;

5 to 15 parts by weight of a solidifying agent;

5 to 25 parts by weight of a thickener;

7.5 to 10 parts by weight of water; And

And 1 to 10 parts by weight of a fertilizer component.

The bauxite residue SiO ₂ 5 ~ 40% by weight, Al ₂ O ₃ 15 ~ 25 _{weight%, Fe 2 O 3 10 ~} 45 wt%, CaO 1 ~ 10 wt%, MgO 0 ~ 3 wt%, K ₂ 0 to 5% by weight of O 2, 2 to 15% by weight of Na ₂ O, 3 to 15% by weight of TiO ₂ , 0 to 1% by weight of MnO ₂ , 0 to 1% by weight of P ₂ O ₅ and 5 to 45% , ≪ / RTI > 10-15.

The solidifying agent is selected from the group consisting of molasses, gum arabic, sodium alginate, glycerin, gelatin, microcrystalline cellulose, pitch, carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, sodium polyacrylate, polyvinylpyrrolidone, alumina sol, Sodium polyphosphate, lignin sulfonates, polyvinyl alcohol, polyethylene glycols, surfactants, starch, thermoset resin materials, or combinations thereof.

The thickener may include bentonite, clay, kaolin, sericite, talc, acid clay, pumice, silica sand, zircon, zeolite, perlite, vermiculite, rice hull, sawdust, wood flour, pulp flock, soy flour or combinations thereof.

The fertilizer component may comprise urea, phosphoric acid, potassium, manganese, boron or a combination thereof.

According to another aspect of the present invention,

And a soil conditioner prepared from the composition for preparing a soil conditioner.

According to another aspect of the present invention,

And introducing the soil amendment agent into an acidic soil.

The pH of the acidic soil may be 4 to 6, and the pH of the soil conditioner may be 10 to 11.

The amount of the soil improving agent may be 1 to 10 parts by weight based on 100 parts by weight of the acidic soil.

The soil improvement method may further include curing the combination of the acid soil and the soil conditioner.

The soil conditioner prepared from the composition for preparing a soil conditioner according to one embodiment of the present invention provides a soil favorable for plant growth by neutralizing acidic soil while preventing or suppressing contamination of soil and groundwater due to heavy metal leaching, Can be improved.

1 is a schematic diagram of a soil conditioner according to an embodiment of the present invention.
FIG. 2 is a graph showing the pH of the modified soil according to the addition ratio of the soil conditioner and the curing period.

Hereinafter, the composition for preparing a soil conditioner according to an embodiment of the present invention will be described in detail.

The composition for preparing a soil conditioner according to an embodiment of the present invention comprises 100 parts by weight of bauxite residue, 5 to 15 parts by weight of a solidifying agent, 5 to 25 parts by weight of a thickener, 7.5 to 10 parts by weight of water and 1 to 10 parts by weight of a fertilizer component .

The bauxite residues (bauxite residue) is red mud, jeokto, as referred to as red mud or scarlet clay (scarlet clay), aluminum hydroxide by the Bayer process from bauxite mineral (Al (OH) ₃₎ and alumina (Al ₂ O ₃ ) is a byproduct of the production process.

The bauxite residue SiO ₂ 5 ~ 40% by weight, Al ₂ O ₃ 15 ~ 25 _{weight%, Fe 2 O 3 10 ~} 45 wt%, CaO 1 ~ 10 wt%, MgO 0 ~ 3 wt%, K ₂ 0 to 5% by weight of O 2, 2 to 15% by weight of Na ₂ O, 3 to 15% by weight of TiO ₂ , 0 to 1% by weight of MnO ₂ , 0 to 1% by weight of P ₂ O ₅ and 5 to 45% .

In addition, the bauxite residue may have a pH of 10-15.

The solidifying agent plays a role of assembling the composition for preparing the soil improving agent including the solidifying agent. Such a solidifying agent can ensure physical and chemical stability without deteriorating the quality of the fertilizer component when the composition for preparing a soil conditioner contains a fertilizer component.

The composition for preparing the soil modifying agent is different from the soil modifying agent described later in that it is not granulated unlike the soil modifying agent and has a smaller amount of water than the soil modifying agent.

The solidifying agent is selected from the group consisting of molasses, gum arabic, sodium alginate, glycerin, gelatin, microcrystalline cellulose, pitch, carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, sodium polyacrylate, polyvinylpyrrolidone, alumina sol, Sodium polyphosphate, lignin sulfonates, polyvinyl alcohol, polyethylene glycols, surfactants, starch, thermoset resin materials, or combinations thereof.

If the amount of the solidifying agent is less than 5 parts by weight based on 100 parts by weight of the bauxite residue, the amount of water used in the preparation of the soil modifying agent increases to cause aggregation between solids. When the soil modifying agent exceeds 15 parts by weight, The amount of water used in the production of the granules may be reduced and the granulation may not be smoothly performed.

The thickener is mixed with another material and has a property of sticking other materials to each other. In addition, the thickener has a property of absorbing water and expanding to 10 times or more of its own volume, and does not have chemical activity and does not affect the chemical properties of other adhesive substances.

The thickener may be selected from the group consisting of bentonite, clay, kaolin, sericite, talc, acid clay, pumice, silica, silica, zeolite, perlite, vermiculite, rice hull, sawdust, woody powder, pulp floc, soybean flour, As shown in FIG.

If the amount of the thickener is less than 5 parts by weight based on 100 parts by weight of the bauxite residue, the rate of elution of the components contained in the soil improver is excessively fast. If the amount of the thickener is more than 25 parts by weight, But also the elution of the components contained in the soil conditioner may not occur well.

If the content of the above-mentioned fertilizer component is less than 1 part by weight with respect to 100 parts by weight of the bauxite residue, the effect of adding fertilizer is insignificant, and if it exceeds 10 parts by weight, a harmful effect may occur.

The fertilizer component may comprise urea, phosphoric acid, potassium, manganese, boron or a combination thereof.

If the amount of the water in the composition for preparing a soil conditioner is less than 7.5 parts by weight based on 100 parts by weight of the bauxite residue, the granulation ratio during the production of the soil conditioner is lowered. If the water content exceeds 10 parts by weight, It can occur and cause lumps.

Another embodiment of the present invention provides a soil conditioner prepared from the composition for preparing the soil conditioner.

1 is a schematic diagram of a soil conditioner 10 according to an embodiment of the present invention.

1, a soil amendment agent 10 according to one embodiment of the present invention may include bauxite residues 11, a solidifying agent 12, a thickener 13 and optionally a fertilizer component 13 have.

In addition, although not shown in Fig. 1, the soil conditioner 10 may further comprise water.

Hereinafter, a method for producing a soil conditioner according to an embodiment of the present invention will be described in detail.

A method for preparing a soil conditioner according to an embodiment of the present invention includes the steps of (S10) obtaining a bauxite residue in an aluminum production process, (20) drying the bauxite residue, 5 to 15 parts by weight of a solidifying agent and 5 to 25 parts by weight of a thickener to obtain a solid mixture (S30), and 7.5 to 10 parts by weight of water are added to a molding machine to 100 parts by weight of the solid mixture and the bauxite residue And continuously or intermittently adding (S40) rotating the molding machine.

In the step S10, the aluminum production process is not limited to aluminum production processes both at home and abroad.

In the step (20), the drying may be performed at 100 to 200 ° C for 1 to 24 hours.

In step S30, 1 to 10 parts by weight of a fertilizer component may be further added to 100 parts by weight of the bauxite residue.

In the step S40, the molding machine may be of a fan type or a drum type.

In addition, the molding machine may be configured such that the contact surface with the solid mixture has a slope of 45 to 55 degrees with respect to the gravity direction.

Further, the solid mixture can be injected into the molding machine in the gravity direction while the contact surface of the molding machine rotates at a rotation speed of 30 to 80 rpm. As a result, the solid mixture can be poured into the contact surface of the molding machine at a slope of 45 to 55 °, and then rotated along the contact surface.

The rotational speed of the contact surface and the slope of the contact surface determine the size and strength of the soil conditioner to be finally produced.

Further, in the step S40, the solid mixture and the water may be introduced into the molding machine through different injection ports. For example, the inlet for the solid mixture may be in the form of a channel having a U-shaped cross section, and the inlet for water may be in the form of a nozzle.

The method for producing the soil amendment agent may further include drying the resultant of the step S40 (i.e., the granulated soil amendment agent) after the step S40.

Hereinafter, the soil improvement method according to one embodiment of the present invention will be described in detail.

The soil remediation method according to an embodiment of the present invention includes the step of putting the soil remediation agent into an acidic soil.

The pH of the acidic soil may be 4 to 6, and the pH of the soil conditioner may be 10 to 11.

The amount of the soil improving agent may be 1 to 10 parts by weight based on 100 parts by weight of the acidic soil.

If the amount of the soil modifying agent is within the above range, the effect of adding the soil modifying agent is sufficient without generating harmful harm.

The soil improvement method may further include curing the combination of the acid soil and the soil conditioner.

The curing step may be carried out by naturally drying for 1 to 20 days in a space where sunlight is blocked and air passes through.

The soil remediation method can improve the acidic soil having a pH of 4 to 6 to a soil having a pH of 6.0 to 8.0.

In addition, the soil improvement method can provide a soil favorable for plant growth while suppressing or preventing soil and groundwater contamination due to heavy metal leaching.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these embodiments.

Example

Examples 1 to 13 and Comparative Examples 1 to 7: Preparation of soil conditioner

First, the residue of bauxite (25.8% by weight of SiO ₂ , 20.8% by weight of Al ₂ O ₃ , and Fe ₂ O ₃ (by weight) of Al ₂ O ₃ produced in the process of producing aluminum hydroxide in KC of Sambon- 23.8 wt.%, CaO 2.68 wt.%, K ₂ O 0.09 wt.%, Na ₂ O 10.5 wt.%, TiO ₂ 5.39 wt.%, MnO 0.06 wt.%, P ₂ O ₅ 0.03 wt.%) Thickener (bentonite) and fertilizer components were mixed and placed in a pelletizing system and stirred for 1 minute. As a result, a solid mixture was obtained. Potassium (Namhae Chemical Co., Ltd.), phosphoric acid (KG Chemical Co., Ltd., Dragonling) or urea (Taeheung F & G, urea) were used as the fertilizer component.

Thereafter, the solid mixture was slowly dropped to the pan while rotating the pan-type molding machine at a rotation speed of 40 rpm at a fan inclination of 50 °. At the same time, water was added to the fan type molding machine through a nozzle.

Thereafter, the rotation speed of the fan was adjusted to 60 rpm and rotated for 20 minutes. As a result, an assembled soil conditioner was obtained.

The bauxite residues, molasses, bentonite and water used in the preparation of the soil conditioner are shown in Table 1 below. In the following Table 1, the units of each numerical value are parts by weight.

Bauxite
Residue molasses Bentonite water Fertilizer component potassium Phosphoric acid Element Example 1 100 5 15 8.75 0 0 0 Example 2 100 10 15 8.75 0 0 0 Example 3 100 15 15 8.75 0 0 0 Example 4 100 10 5 8.75 0 0 0 Example 5 100 10 25 8.75 0 0 0 Example 6 100 10 15 7.5 0 0 0 Example 7 100 10 15 10 0 0 0 Example 8 100 10 15 8.75 5 0 0 Example 9 100 10 15 8.75 0 5 0 Example 10 100 10 15 8.75 0 0 5 Example 11 100 10 15 8.75 0 One 0 Example 12 100 10 15 8.75 0 10 0 Example 13 100 10 15 8.75 0 0.5 0 Comparative Example 1 100 4 15 8.75 0 0 0 Comparative Example 2 100 16 15 8.75 0 0 0 Comparative Example 3 100 10 4 8.75 0 0 0 Comparative Example 4 100 10 26 8.75 0 0 0 Comparative Example 5 100 10 15 7 0 0 0 Comparative Example 6 100 10 15 11 0 0 0 Comparative Example 7 100 10 15 8.75 0 11 0

Evaluation example

Evaluation Example 1: Evaluation of the properties of soil conditioner

Properties of the soil conditioner prepared in Examples 1 to 13 and Comparative Examples 1 to 7 were visually observed. As a result, the soil remediation agents prepared in Examples 1 to 13, Comparative Examples 3 and 7 showed high granulation ratio and no lumps. However, the soil remediation agents prepared in Comparative Examples 2 and 4 to 5 were not suitable for use as soil remediation agents due to a low granulation ratio, and the soil remediation agents prepared in Comparative Examples 1 and 6 had a large mass And are not suitable for use as a soil conditioner.

Evaluation Example 2: Evaluation of improving effect of acid soil

The soil conditioner prepared in Example 2 was added to acidic soil in various ratios and mixed thoroughly. Thereafter, the following properties were evaluated without curing or curing the mixture. The acidic soil was collected in the forests of the Seokjeong-ri, Geumcheon-myeon, Naju-si, Jeonnam, and the soil of the cropping area, and showed a pH of between 5.0 and 5.5.

(pH measurement)

The pH of the modified soil was measured by varying the addition ratio of the soil conditioner and the curing period, and the results are shown in FIG. In FIG. 2, 1 to 3% means the weight ratio (%) of the soil improving agent to 100% of the acid soil.

Referring to FIG. 2, the higher the soil amendment additive ratio, the higher the pH of the modified soil was, and the higher the pH of the cured soil than the soil that was not cured (i.e., dry mixed). Also, depending on the addition rate of the soil conditioner, the curing period providing the highest pH was different.

(Heavy Metal Elution Test)

In order to investigate the change of heavy metals in the soil after the reaction caused by the rainfall when the soil improvement agent was sprayed on the agricultural land, heavy metal leaching test was carried out as described below, and the results are shown in Table 2 below. In Table 2, the addition ratio of the soil improver means the weight ratio (%) of the soil improving agent to 100% of the acid soil, and "N.D." means the non-detection. In Table 2, the unit of each value is mg / kg.

≪ Heavy metal dissolution test method >

Rainfall was injected into the upper part of the column (20 mm) filled with the acidic soil and the soil improvement agent incorporated therein (average rainfall was applied), the dissolution test was conducted for 90 days and then the residue (that is, acidic soil + soil conditioner) Respectively.

division As CD Pb Cr Cr ⁶⁺ Hg Cu Ni Zn Reference value 25 4 150 300 5 2 150 150 300 A track



Acid soil N.D. N.D. 22.56 7.06 N.D. N.D. 3.39 2.53 45.86 One% N.D. N.D. 22.98 13.32 N.D. N.D. 5.70 3.56 47.14 2% N.D. N.D. 22.79 19.16 N.D. N.D. 4.17 4.47 45.72 3% N.D. N.D. 22.83 26.13 N.D. N.D. 3.83 5.73 45.57 Bauxite
by-product N.D. N.D. 53.85 99.94 0.73 N.D. 326.74 25.93 257.19 B track



Acid soil N.D. N.D. 24.69 6.60 N.D. N.D. 4.58 2.36 45.60 One% N.D. N.D. 23.62 12.31 N.D. 0.06 4.81 3.35 46.30 2% N.D. N.D. 23.99 20.03 N.D. N.D. 5.10 4.63 47.26 3% N.D. N.D. 23.59 24.00 N.D. N.D. 4.22 5.44 46.79 Bauxite
by-product N.D. N.D. 51.49 88.05 1.94 N.D. 291.56 23.38 245.56 C track



Acid soil N.D. N.D. 22.87 7.16 N.D. N.D. 4.16 2.53 44.56 One% N.D. N.D. 21.74 12.27 N.D. N.D. 4.22 3.42 44.74 2% N.D. N.D. 23.41 20.03 N.D. N.D. 4.15 4.81 46.82 3% N.D. N.D. 23.61 26.47 N.D. 0.07 5.25 5.95 50.25 Bauxite
by-product N.D. N.D. 55.92 107.18 2.06 0.07 321.69 26.16 264.98

As shown in Table 2, the elution amounts of heavy metals (As, Cd, Pb, Cr, Cr ⁶⁺ , Hg, Cu, Ni and Zn) were all lower than the standard values. Since the elution amount of the heavy metal is independent of whether the fertilizer component is added or not, the soil amendment agent prepared in Examples 8 to 12 and Comparative Examples 7 to 8 has a similar elution amount of the soil amendment agent and heavy metal prepared in Example 2 .

Evaluation Example 3: Evaluation of water dissolution rate

The soil improving agent prepared in Examples 2, 4, 5, and 3 and Comparative Example 4 was added in an amount of 2 wt% (1 g) based on 100 wt% (50 g) of the acidic soil used in Evaluation Example 2 And then water elution test was carried out by the following method. The results are shown in Table 3 below.

≪ Method of dissolution test of water &

Water was slowly added dropwise to the top of a column (20 mm) filled with a mixture of the soil amendment agent and the acidic soil. Specifically, the mixture was completely wetted, and water was slowly dropped through the mixture to the extent that it did not elute under the column. Thereafter, 30 ml of water was poured into the column to pass through the mixture to measure the elution rate of water eluted under the column. Here, the higher the dissolution rate of water, the higher the dissolution rate of the soil conditioner component.

Example 2 Example 4 Example 5 Comparative Example 3 Comparative Example 4 Elution rate
(ml / min) 0.8 1.0 0.6 2.0 0.1

Referring to Table 3, while the soil modifying agent prepared in Examples 2, 4 and 5 had a suitable water dissolution rate, the soil modifying agent prepared in Comparative Example 3 had a too high water dissolution rate, The amount of bentonite in the soil improvement agent was so high that the rate of water elution was too slow due to the excessive volume expansion of the bentonite. On the other hand, since the dissolution rate of water depends on the content ratio of bentonite in the soil modifying agent, the soil modifying agent prepared in Examples 8 to 13 and Comparative Example 7 is expected to have similar dissolution rates of the soil modifying agent and water prepared in Example 2 .

Evaluation Example 4: Seed Germination Rate Test of Lettuce

As a test crop, we used a green lettuce (world seedling). The concentration used was 200 kg / 10a, and the soil used for the germination test was mixed with 60 wt% of commercial soil and 40 wt% of general soil (i.e., acid soil). The test was repeated using 32 ports (35 cm x 16 cm) and 32 replicates for each treatment and 3 replicates. The duration of the test was 30 days after seeding and soil cultivation, and the seedlings were cultivated in a greenhouse so that the germination rate did not change. The germination rate was examined by naked eye for 21 days from the day after sowing.

Example One 2 3 4 5 6 7 8 9 10 Germination rate (%) 56.3 57.1 55.8 56.7 58.0 59.5 54.7 79.2 87.5 77.0 Example Comparative Example 11 12 13 One 2 3 4 5 6 7 Germination rate (%) 85.2 88.4 61.0 53.6 55.2 56.4 56.2 56.0 52.7 51.8

Referring to Table 4, the soil remediation agents prepared in Examples 8 to 12 showed higher germination rates than the soil remediation agents prepared in Examples 1 to 7 and Comparative Examples 1 to 7. In particular, the soil amendments made in Examples 9, 11 and 12 comprising phosphoric acid as a fertilizer component were found to have a higher germination rate than the soil amendments prepared in Examples 8 and 10 comprising urea or potassium as a fertilizer component . On the other hand, the soil conditioner produced in Comparative Example 7 containing a large amount of phosphoric acid as a fertilizer component (i.e., 11 parts by weight phosphoric acid relative to 100 parts by weight of bauxite residue) showed a very low germination rate, It is believed that this was caused by the occurrence of a harm (药害).

Although the present invention has been described with reference to the drawings and embodiments, it is to be understood that various changes and modifications may be suggested to those skilled in the art. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

10: soil conditioner 11: bauxite residue
12: Solidifying agent 13: Thickener
14: Fertilizer component

Claims (10)

100 parts by weight of bauxite residue;
5 to 15 parts by weight of a solidifying agent;
5 to 25 parts by weight of a thickener;
7.5 to 10 parts by weight of water; And
1 to 10 parts by weight of a fertilizer component,
The solidifying agent is selected from the group consisting of molasses, gum arabic, sodium alginate, glycerin, gelatin, microcrystalline cellulose, pitch, carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, sodium polyacrylate, polyvinylpyrrolidone, alumina sol, Sodium polyphosphate, lignin sulfonate, polyvinyl alcohol, polyethylene glycol, surfactants, starch, thermosetting resin materials or a combination thereof,
Wherein the thickener is selected from the group consisting of bentonite, clay, kaolin, sericite, talc, acid clay, pumice, silica, zircon, zeolite, perlite, vermiculite, rice hull, sawdust, wood flour, pulp flock, soy flour,
Wherein the fertilizer component comprises urea, phosphoric acid, potassium, manganese, boron or a combination thereof. The method according to claim 1,
The bauxite residue SiO ₂ 5 ~ 40% by weight, Al ₂ O ₃ 15 ~ 25 _{weight%, Fe 2 O 3 10 ~} 45 wt%, CaO 1 ~ 10 wt%, MgO 0 ~ 3 wt%, K ₂ 0 to 5% by weight of O 2, 2 to 15% by weight of Na ₂ O, 3 to 15% by weight of TiO ₂ , 0 to 1% by weight of MnO ₂ , 0 to 1% by weight of P ₂ O ₅ and 5 to 45% , And a pH of 10 to 15. delete delete delete A soil conditioner prepared from the composition for preparing a soil conditioner according to claim 1 or 2. A soil improvement method comprising the step of applying the soil conditioner according to claim 6 to an acidic soil. 8. The method of claim 7,
Wherein the pH of the acidic soil is between 4 and 6 and the pH of the soil conditioner is between 10 and 11. 8. The method of claim 7,
Wherein the amount of the soil improving agent is 1 to 10 parts by weight per 100 parts by weight of the acidic soil. 8. The method of claim 7,
Further comprising curing a combination of said acid soil and said soil conditioner.

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