JP4096206B2 - Composition containing ferrous oxide for promoting plant growth - Google Patents

Description

The present invention relates to a ferrous oxide-containing composition for promoting plant growth (hereinafter referred to as a ferrous oxide-containing composition) . More specifically, the present invention relates to a ferrous oxide-containing composition containing ferrous oxide and a composite oxide having elements such as Ca and Al.
The ferrous oxide-containing composition of the present invention can be used in various applications such as plant growth promoters, plant mineral supply promoters, and plant sugars, polyphenols, vitamins and the like. In particular, it is useful as a plant growth promoter in the growth of various plants. For example, it activates photosynthesis in leaf stem vegetables such as spinach, cabbage, and Chinese cabbage to promote the formation of chlorophyll, such as radish, onion, carrot, etc. Root vegetables and sweet potatoes such as sweet potato and potato can be sufficiently grown in a short period of time, and the sugar content of fruit vegetables such as melon can be increased.

  Although iron is a trace element for plants, it is an essential element, and is usually contained in crops in an amount of about 1 to 400 ppm. If it is deficient, trace deficiency will occur. For example, iron is involved in the formation of chlorophyll, and when deficient, the leaves turn yellow. Iron is also involved in nitrogen metabolism, and deficiency impairs protein synthesis. In order to supply iron, which is an essential element for plant growth, the use of iron powder, converter slag, iron hydroxide, or the like has been proposed as an iron-containing composition (see, for example, Patent Document 1).

  Furthermore, in order to supply iron to plants, iron is added to sulfuric acid, hydrochloric acid, nitric acid, etc., and aqueous solutions dissolved in water as iron sulfate, iron chloride, iron nitrate, etc. are provided to customers as fertilizers in liquid form. ing. The hydrogen ion exponent (hereinafter referred to as “pH”) of this aqueous solution is usually 2 to 3, and if the pH is 5 or less, the solubility is sufficiently high and kept in a liquid state. In addition, liquid or powder fertilizers containing chelated iron using a chelating agent such as ethylenediaminetetraacetic acid (EDTA) are also provided.

JP-A-8-277183

However, most of the iron eluted from the iron-containing composition described in Patent Document 1 precipitates as ferric hydroxide and, for example, cannot be taken up by plants and is an essential element for plants. Some iron could not be supplied enough.
Even in a liquid fertilizer containing iron sulfate or the like, dissolved iron may precipitate as ferric hydroxide due to sunlight or air, and the plant may not be able to take up. Furthermore, chelated iron has a problem that a chelating agent such as EDTA which remains after being supplied to a plant and taken into the plant easily binds to heavy metals in the soil. That is, heavy metals such as Pb and Cd are usually present in the soil as oxides that are insoluble in water, but when the remaining chelating agent and heavy metal are combined to form a chelate, this chelate dissolves in groundwater. May cause heavy metal contamination.

  The present invention solves the above-described conventional problems, and contains ferrous oxide and a composite oxide, and divalent iron ions eluted from the ferrous oxide into water are ferric hydroxide. An object of the present invention is to provide a ferrous oxide-containing composition that is prevented from being precipitated in the same manner.

When contacted with water, ferrous oxide is easily soluble if the pH is low, but hardly soluble if the pH is high. Since the pH of soil is generally about 6.0, when a plant growth promoter containing ferrous oxide is used to supply iron to plants, the ferrous oxide dissolves in water and divalent iron. Ions elute. However, when the pH is about 6.0, ferric hydroxide and the like are easily generated, that is, divalent iron easily becomes trivalent iron, becomes insoluble in water, precipitates, and is taken up by plants. Can not be.
On the other hand, the ferrous oxide-containing composition of the present invention contains a specific complex oxide having elements such as Ca, Al, and Mg in addition to ferrous oxide. By gradually eluting ions, Al ions, Mg ions, etc., the pH is maintained at 7.0 or higher. Therefore, the supply of iron is stably continued, and the growth of the plant is promoted. In addition, since iron is stably supplied on the alkali side in this way, even when used in alkaline soil, which is said to be about 20% of the world soil, it functions sufficiently as a plant growth promoter.
In addition, when CaO etc. are mix | blended with ferrous oxide, the pH of soil can be made high, but in this case, Ca ions etc. elute at a stretch from CaO etc., and pH is temporarily, for example, 12.0 To a high degree. However, since the eluted Ca ions etc. flow into the ground water and are washed away by the subsequent rainfall and the like, and there are no Ca ions etc. to maintain a high pH, ferrous oxide is hardly soluble in water. It becomes ferric hydroxide or the like, and the plant cannot take in, and the action and effect do not continue.
The present invention has been made based on such knowledge.

The present invention is as follows.
1. Ferrous oxide, CaAl ₂ O ₄ , FeAl ₂ O ₄ , MgAl ₂ O ₄ , CaFeSi ₂ O ₆ , MgFeSi ₂ O ₆ , CaSi ₂ O ₅ , MgSi ₂ O ₅ , CaFe ₂ O ₄ , MgFe ₂ O ₄ , CaFeO ₂ and at least one composite oxide and the ferrous-containing oxidizing composition, characterized in that it contains one of the MgFeO _2.
2 . The composite oxide is CaAl ₂ O ₄ and FeAl ₂ O ₄ . The ferrous oxide-containing composition described in 1.
3 . When the ferrous oxide-containing composition is 100 parts by mass, the total of the ferrous oxide and the composite oxide Ri der than 65 parts by weight, and oxidizing ferrous 58.5～ 99.5 parts by weight, the composite oxide is 0.325 to 10 parts by mass the above 2. The ferrous oxide-containing composition described in 1.
4 . Hydrochloric acid aqueous solution of hydrogen ion exponent 2.2, the ferrous oxide-containing composition was added in an amount of mass ratio of 10 mass%, the hydrogen ion exponent measured after 24 hours at 8.0 to 12.0 There, and hydrogen ion exponent measured after 264 hours Ri der 7.5 to 11.0, the divalent iron ions is suppressed to precipitate a ferric hydroxide 3. The ferrous oxide-containing composition described in 1.
5 . When the amount of Al and Ca contained in an aqueous solution prepared by adding the above ferrous oxide-containing composition to a hydrochloric acid aqueous solution having a hydrogen ion index of 2.2 to a mass ratio of 10% by mass is determined after 264 hours of a content 70～130Mg / liter Al, the 4 content of Ca is 90～170Mg / liter. The ferrous oxide-containing composition described in 1.

When the ferrous oxide-containing composition of the present invention is brought into contact with water, it is suppressed that divalent iron ions eluted in water are precipitated as ferric hydroxide and the like. Therefore, divalent iron ions dissolved in water can be efficiently absorbed by plants. For example, when used as a plant growth promoter, formation of chlorophyll and protein synthesis are promoted, such as melon. Fruits and vegetables produce actions and effects such as an increase in sugar content.
Further, when the composite oxide is CaAl ₂ O ₄ and FeAl ₂ O ₄ is eluted divalent iron ions may become the second iron hydroxide, etc., it is effectively suppressed.
Further, the present ferrous oxide-containing composition is 100 parts by state, and are total 65 parts by mass or more of a ferrous composite oxide oxidation and oxidizing ferrous 58.5～ When 99.5 parts by mass and the composite oxide is 0.325 to 10 parts by mass , divalent iron ions can be dissolved in water as they are for a longer period of time.
Further, the ferrous oxide-containing composition was added to a hydrochloric acid aqueous solution having a hydrogen ion index of 2.2 so that the mass ratio was 10% by mass, and the hydrogen ion index measured after 24 hours was 8.0-12. 0, and the hydrogen ion exponent measured after 264 hours Ri der 7.5 to 11.0, if that divalent iron ions are precipitated in a ferric hydroxide is suppressed, plants When used as a growth promoter, iron can be absorbed by the plant over a long period of time, and the effect of promoting growth is great.
Furthermore, Al and Ca contained in an aqueous solution prepared by adding the ferrous oxide-containing composition to a hydrochloric acid aqueous solution having a hydrogen ion index of 2.2 to a mass ratio of 10% by mass were determined after 264 hours. When the Al content is 70 to 130 mg / liter and the Ca content is 90 to 170 mg / liter, the pH of the solution can be kept higher, and the divalent iron ions Precipitation as iron dihydroxide or the like is sufficiently suppressed.

FIG. 2 is a schematic explanatory view of an FeO powder production apparatus used in Example 1. It is explanatory drawing using the chart (2 (theta) is 10-50) of the X-ray diffraction of the FeO powder manufactured in Example 1. FIG. It is explanatory drawing using the chart (2 (theta) 50-100) of the FeO powder manufactured in Example 1. FIG. It is a graph which shows the time-dependent change of pH of the aqueous solution which dissolved FeO powder. It is a graph which shows the time-dependent change of pH of the aqueous solution which dissolved reagent FeO. It is a graph which shows the time-dependent change of pH of the aqueous solution at the time of replacing | exchanging the solvent of the aqueous solution which dissolved FeO powder with the acidic solvent timely. 2 is an explanatory diagram using an SEM photograph of FeO powder produced in Example 1. FIG. 3 is an explanatory diagram using a chart of EDX qualitative analysis of FeO powder produced in Example 1. FIG. It is explanatory drawing using the SEM photograph of the red rust part of the FeO powder taken out from the aqueous solution which dissolved FeO powder 21 days afterward. It is explanatory drawing using the chart of the EDX qualitative analysis of the red rust part of the FeO powder taken out from the aqueous solution in which FeO powder was dissolved after 21 days. It is explanatory drawing using the SEM photograph of the part which has not generate | occur | produced the red rust of the FeO powder taken out after 21 days progress from the aqueous solution which dissolved FeO powder. It is explanatory drawing using the chart of the EDX qualitative analysis of the part which has not generate | occur | produced the red rust of the FeO powder taken out after 21 days progress from the aqueous solution which dissolved FeO powder. It is explanatory drawing using the X-ray-diffraction chart of the FeO powder taken out after 21 days progress from the aqueous solution in which FeO powder was dissolved. It is explanatory drawing using the chart of the X-ray diffraction of the FeO powder taken out after the elapse of 11 days from the aqueous solution in which the reagent FeO is dissolved. It is explanatory drawing by the photograph which compares and shows the size of the carrot harvested from the cultivation plot using a soil type growth promoter, and the carrot harvested from the control plot. It is explanatory drawing by the photograph which shows the magnitude | size of the peanut harvested from the cultivation division using a soil type growth promoter, and the size of the peanut harvested from the control plot. It is explanatory drawing by the photograph which compares and shows the magnitude | size of the Chinese cabbage harvested from the cultivation plot using a soil type growth promoter, and the Chinese cabbage harvested from the control plot.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1; Material supply system, 11; Hopper, 2; Vacuum heating system, 21; Vacuum heating furnace, 211, 212, 213, 214, 215; Heating chamber, 22; Discharge feeder, 23; Stirrer, 231; Shaft, 232; Rotating blade, 233; stirring member, 234; motor, 24; bottom of vacuum heating furnace, 251, 252, 253, 254, 255; heater, 26; cooling system, 4;

Hereinafter, the present invention will be described in detail.
[1] Ferrous oxide-containing composition The “ferrous oxide-containing composition” contains ferrous oxide and a specific composite oxide.
The above “ferrous oxide” is a substance having a NaCl-type crystal structure and mainly composed of iron and oxygen. This ferrous oxide may contain a substance in which part of the iron atom is substituted with a transition metal atom or the like, and a substance in which a part of the oxygen atom is substituted with another element such as a halogen element. . Moreover, the substance which has an atomic vacancy may be contained. This ferrous oxide is usually in powder form.
In addition, it is preferable that ferrous oxide is contained 65 mass% or more when the total of ferrous oxide and complex oxide is 100 mass%. This content is more preferably 90 to 99.5% by mass, particularly preferably 93 to 97% by mass. The content of ferrous oxide can be measured by a method such as an X-ray diffraction method, for example.

The “composite oxide” includes CaAl ₂ O ₄ , FeAl ₂ O ₄ , MgAl ₂ O ₄ , CaFeSi ₂ O ₆ , MgFeSi ₂ O ₆ , CaSi ₂ O ₅ , MgSi ₂ O ₅ , CaFe ₂ O ₄ , MgFe _2. It is at least one of O ₄ , CaFeO ₂ and MgFeO ₂ . When 2 or more types of complex oxide is contained, any complex oxide may be sufficient and it does not specifically limit. The composite oxide may further contain other elements, and the other elements are often at least one of Fe and Si. The composite oxide may have Zn and Mn as other elements.

As the complex oxide, CaAl ₂ O ₄ , FeAl that can sufficiently suppress the precipitation of divalent iron ions eluted from ferrous oxide into ferric hydroxide or the like. ₂ O ₄ , CaFeSi ₂ O ₆ and CaSi ₂ O ₅ are more preferable. These composite oxides may also contain only 1 type, and may contain 2 or more types. When 2 or more types of complex oxide is contained, any complex oxide may be sufficient and it does not specifically limit. Among these complex oxides, CaAl ₂ O ₄ is such that Ca ions and Al ions are continuously eluted, and thereby divalent iron ions are precipitated as ferric hydroxide and the like. Can be reliably suppressed, which is preferable. In addition, FeAl ₂ O ₄ is a hydroxide that selectively elutes Al ions and divalent iron ions that elute from ferrous oxide precipitate as ferric hydroxide and the like. Since it is suppressed, it is preferable. Furthermore, CaFeSi ₂ O ₆ and CaSi ₂ O ₅ is, Ca ions are continuously eluted, is suppressed to the same manner as described above are divalent iron ions resulting in precipitation become ferric hydroxide Therefore, it is preferable.
This composite oxide is produced, for example, when a ferrous oxide-containing composition is produced by the method described later. The type of composite oxide to be generated varies depending on the raw materials used, production conditions, and the like. For example, at least one of the various composite oxides as described above is generated. The same effect | action and effect that it is suppressed that a valent iron ion precipitates as ferric hydroxide etc. are show | played.

  Content of complex oxide can be 0.3-15 mass% when the sum total of ferrous oxide and complex oxide is 100 mass%. The content of this complex oxide is preferably 0.5 to 10% by mass, particularly preferably 3 to 7% by mass. If the content of the composite oxide is 0.3 to 15% by mass, particularly 0.5 to 10% by mass, and further 3 to 7% by mass, divalent iron ions eluted from ferrous oxide into water are water. Precipitation as ferric oxide or the like can be sufficiently suppressed.

In addition to ferrous oxide and the specific composite oxide, the ferrous oxide-containing composition contains metallic iron, MgO, CaO, Al ₂ O ₃ , Fe ₂ O ₃ , ZnO, MnO, and the like. It may be. The content of these other components is preferably 35 parts by mass or less, more preferably 25 parts by mass or less, particularly 15 parts by mass or less, when the ferrous oxide-containing composition is 100 parts by mass. More preferred. If the content of the other components is 35 parts by mass or less, the content of the ferrous oxide-containing composition is ensured, and as a result, sufficient iron ions can be supplied. It is sufficiently suppressed that the divalent iron ions eluted into the iron precipitate as ferric hydroxide and the like.
In addition, it is preferable that water does not contain negative ions, such as Cl ions, which react with Ca ions and Al ions eluted from the composite oxide to form compounds that are hardly soluble or insoluble in water. When it is contained, the smaller the content, the better.

  In this ferrous oxide-containing composition, when the composition was added to a hydrochloric acid aqueous solution having a pH of 2.2 at a mass ratio of 10% by mass, the pH after 24 hours was 8.0 to 12.0. And the pH after 264 hours can be adjusted to 7.5 to 11.0. This pH can in particular be 9.5 to 11.5 after 24 hours and 8.0 to 10.0 after 264 hours. If the pH after 24 hours is 8.0 to 12.0, and the pH after 264 hours is 7.5 to 11.0, divalent iron ions eluted from ferrous oxide into the water will be dihydric hydroxide. Sedimentation as iron or the like is sufficiently suppressed. For example, when used as a plant growth promoter, iron can be absorbed efficiently by plants, and plant growth can be sufficiently promoted. it can.

Further, in this ferrous oxide-containing composition, Al and Ca contained in an aqueous solution prepared by adding the composition to a hydrochloric acid aqueous solution of pH 2.2 so as to have a mass ratio of 10% by mass are added after 264 hours. When quantified, the Al content can be 70 to 130 mg / liter, particularly 85 to 120 mg / liter, and the Ca content can be 90 to 170 mg / liter, particularly 100 to 160 mg / liter. . Thus, even after a long time has elapsed since the preparation of the solution, a large amount of Al and Ca are eluted, so that the pH after 264 hours can be kept sufficiently high as described above. It is sufficiently suppressed that the valent iron ions are precipitated as ferric hydroxide or the like.
In addition, even if it is hydrochloric acid aqueous solution with pH as low as 2.0-3.0, content of Ca can be 130-170 mg / liter, especially 140-160 mg / liter. Thus, even when the initial pH is low, it is presumed that the pH of the liquid can be sufficiently increased by elution of Ca.
This element can be quantified by, for example, high frequency inductively coupled plasma emission spectroscopy.

[2] Method for producing ferrous oxide-containing composition The method for producing the ferrous oxide-containing composition of the present invention is not particularly limited, and examples thereof include the following production methods.
That is, a granulation step of granulating iron-containing dust to form a granulated product, a heating step of heating the granulated product under vacuum, and iron content contained in the granulated product to FeO, And a cooling step of rapidly cooling the FeO under vacuum.
Hereinafter, the powder of the ferrous oxide-containing composition produced by such a method is referred to as “FeO powder”.
As the dust containing iron, forged shot dust collected in the forging process, electric furnace dust, blast furnace dust, converter dust, cupola dust, and the like generated in the steel making process can be used.

These dusts are not particularly limited as long as they contain iron. Further, the iron content is not limited. The dust is usually powder, but is not limited thereto, and may be small pieces or a mixture of powder and small pieces. In the case of powder, the average particle size is usually 3 to 10 μm. The iron content is contained in the dust as iron oxide or as a mixture of iron oxide and metallic iron. The metallic iron contained in the dust is preferably 40% by mass when the total iron content is 100% by mass. Hereinafter, it is particularly preferably 30% by mass or less (may be 0% by mass). Only one type of dust may be used, or two or more types of dust may be used.
In addition to iron, the dust may contain Zn, Ni, Cu, Mn, etc., and these may be a single metal or a compound such as an oxide.

  It is preferable to remove the chlorine from the dust by washing with water, and then remove the washing water in which the chlorine is dissolved, and then granulate. By reducing the chlorine concentration contained in the dust in this way, dust aggregation during vacuum heating can be suppressed.

The reason why the dust is made into a granulated product in the granulation step is to promote the reaction from Fe ₂ O ₃ , Fe ₃ O ₄ and Fe (single) to FeO during vacuum heating. This granulated product is obtained by solidifying a mixture of dust and treatment material, etc., and solidifying the mixture of dust and treatment material in order to maintain the shape of the granulated product. An appropriate amount of the treatment material is blended depending on the iron content contained in the dust and the types of other metals and their contents.

  As the treatment material, for example, when the iron content in the dust is small, a large amount of FeO powder is produced, and cutting waste and polishing containing iron used for the purpose of efficiently producing the FeO powder, etc. Examples include scraps and iron powder. Moreover, a reducing agent can also be mix | blended for the purpose of collect | recovering the other metals contained in dust, etc. as a simple substance etc. of reaction. In particular, when the dust contains zinc (usually contained as ZnO) and is recovered as a simple zinc at the same time as the production of FeO powder, in addition to cutting waste and polishing waste containing iron, iron powder, etc. It is preferable to use a reducing agent such as a reducing agent used for pig iron and steel, and a waste material containing a large amount of carbon such as tire scrap. This reducing agent may be used alone or in combination of two or more.

  When other processing materials such as a reducing agent are used, the shape is not particularly limited as long as it can be blended with dust to form a granulated product together with dust, but the shape is powder, granule, small piece, etc. Can be used. In particular, when used as a reducing agent, in consideration of the efficiency of each reaction and reduction of oxides of other metals contained in the dust, it is preferable that the powder be contactable more. In the case of powder, the average particle diameter is not particularly limited, but can be 200 μm or less, and preferably 180 μm or less. The lower limit of the average particle size is up to fine powder that is easy to obtain and handle.

  When the reducing agent is used, the mixing ratio of the dust and the reducing agent is not particularly limited, but when the dust is 100 parts by mass, the reducing agent is preferably 100 parts by mass or less, particularly preferably 90 parts by mass or less, and more preferably. 80 parts by mass or less (usually 30 parts by mass or more). When the reducing agent exceeds 100 parts by mass, the processing efficiency decreases. On the other hand, if the amount is less than 30 parts by mass, oxides of other metals such as zinc oxide may not be sufficiently reduced.

The granulated product is produced by further blending a binder with a mixture of dust and other treatment materials. As the binder, there is used alumina cement that does not cause a problem of smoke and odor even if it volatilizes, and can generate the specific composite oxide. The amount of the alumina cement is preferably 3 to 20 parts by mass, particularly preferably 3 to 15 parts by mass, and more preferably, when the total of dust or a mixture of dust and other treatment materials is 100 parts by mass. Is 3-12 parts by mass. When the blending amount is less than 3 parts by mass, it is not easy to produce a granulated product due to a small amount of binder, and when it exceeds 20 parts by mass, the granulated product may become brittle and generation of a gas derived from the binder. Since the amount may increase, it is not preferable.
In addition, in order to make it react efficiently, it is preferable to remove the water | moisture content of a granulated product by drying etc., and to use for a heating process after that.

  The shape of the granulated product is not particularly limited, and may be any of a sphere, an ellipsoid, a hemisphere, a cube, a cuboid, a cylinder, a briquette, and the like. The granulated product may be a dense body or a porous body. Furthermore, in order to transfer heat to the whole granulated product or to maintain the shape of the granulated product during heating, the diameter of the granulated product is considered in consideration of heat conduction from the start of heating until reaching a predetermined temperature. The diameter (when it is a sphere, the maximum passing dimension when it is another shape) is preferably 25 mm or less, particularly preferably 15 mm or less, and further preferably 10 mm or less (usually 3 mm or more). When the diameter exceeds 25 mm, it is not preferable because the inside of the granulated product hardly reaches a predetermined temperature. On the other hand, if it is less than 3 mm, the granulated product may aggregate and time may be required for the reaction.

  A heating process is a reaction process for producing | generating FeO powder. In other words, the granulated product is heated under vacuum, and the iron content contained in the granulated product is changed to FeO. Further, when the dust contains an oxide of another metal, for example, zinc oxide, metal zinc and FeO are generated by the reaction of zinc oxide and metal iron. Usually, since it evaporates under a high vacuum of about 1.56 kPa, it can be recovered as metallic zinc in the heating step. In this case, the heating process for converting the iron contained in the dust or the like into FeO also serves as a recovery process for recovering other metals such as zinc as a simple metal.

The degree of vacuum in the heating step is preferably set so that FeO is efficiently generated, and this degree of vacuum can be set to 0.1 to 13.3 kPa, preferably 2.6 to 13.3 kPa. Preferably it is 4.0-6.7 kPa. When the degree of vacuum is too low, a lot of metallic iron tends to remain without being oxidized. On the other hand, if the degree of vacuum is too high, the generated FeO tends to be oxidized to Fe ₃ O ₄ , and further, oxides of other metals, such as zinc oxide, may be difficult to reduce.
Although this vacuum atmosphere contains a small amount of oxygen, the atmosphere in the heating process can be an inert gas atmosphere having an oxygen partial pressure equivalent to this vacuum atmosphere.

  The heating process is performed in the vacuum atmosphere described above. This heating may be a method of raising the temperature of the granulated product from room temperature to a predetermined temperature and maintaining the predetermined temperature. The granulated product is put in an atmosphere set in advance at a temperature lower than the predetermined temperature, Alternatively, the temperature may be raised to a temperature and the predetermined temperature may be maintained. Alternatively, a method may be used in which the granulated product is put into an atmosphere set in advance at a predetermined temperature and the predetermined temperature is maintained. Among these heating methods, a method of raising the temperature of the granulated product from room temperature to a predetermined temperature and maintaining the predetermined temperature is particularly preferable because powderization of the granulated product is further suppressed. Furthermore, the rate of temperature increase when the temperature is increased is not particularly limited.

  The predetermined temperature in the heating step is preferably 600 to 1100 ° C, particularly preferably 800 to 950 ° C. If the heating temperature is less than 600 ° C., the recovery rate as FeO is low, and if it exceeds 1100 ° C., dust may melt, which is not preferable. Furthermore, in order to recover other metals excluding iron as a single metal, the heating temperature is preferably set to 800 ° C. or higher when the granulated product containing the reducing agent or the like is subjected to heat treatment. Moreover, if it is high temperature, it must be a heating furnace with high heat resistance, and in particular, an expensive refractory and a special sealing material for making a vacuum atmosphere are required, so the heating temperature is 950 ° C. or less. It is preferable to do.

  The heating time in the heating step is not limited as long as the entire granulated product can be heated to a uniform temperature. This heating time is preferably 30 minutes or more, particularly preferably 30 minutes or more and 6 hours or less. If the heating time is too short, FeO may not be generated sufficiently. On the other hand, if the heating time is too long, the FeO powder tends to aggregate and the productivity tends to decrease, which is not preferable. The combination of the heating temperature and the heating time is preferably 90 minutes or more when the temperature is 800 to 850 ° C, and 60 minutes or more when the temperature is 850 to 900 ° C. It is preferable that when the temperature is 900 to 950 ° C., the time is preferably 30 minutes or more.

  The granulated product is usually heated using a heat treatment furnace. The heat treatment furnace is not particularly limited as long as it includes at least a heater and can uniformly heat the granulated product to be charged. Examples of the heat treatment furnace include a roller hearth furnace and a rotary kiln. The granulated product is pulverized by, for example, a stirring means having a stirring blade while moving in the heat treatment furnace. This heat treatment furnace may be provided with a recovery device for recovering metallic zinc or the like produced by the reduction. The amount of granulated product input to the heat treatment furnace is not particularly limited, but considering the heat conduction to the entire granulated product heated in the heat treatment furnace, the average height of the granulated product sprayed on the hearth is usually The input amount is preferably 100 mm or less, particularly 80 mm or less, and more preferably 30 mm or less.

  In general, it is preferable that the collector disposed for recovering metal zinc or the like is in a vacuum atmosphere to prevent oxidation of metal zinc or the like, or at least to suppress oxidation. Metallic zinc or the like is melted in the recovery device, and then solidified into an ingot. The ingot is preferable because the recovered metal can be easily handled later.

The cooling step is a step for holding the FeO powder generated by the heating step as “FeO” powder. In this cooling step, the FeO powder is rapidly cooled in a vacuum atmosphere. The degree of vacuum is preferably 13.3 kPa or less, particularly preferably 6.7 kPa or less, and further preferably 1.33 kPa or less (usually 0.133 kPa or more). If the degree of vacuum is low, FeO may be oxidized to Fe ₃ O ₄ or Fe ₂ O ₃ or the like. Furthermore, the temperature lowering rate at the time of rapid cooling can be 100 to 450 ° C./min, and preferably 200 to 450 ° C./min. When the temperature lowering rate is too small, that is, when a long time is required for temperature lowering, FeO may be oxidized to Fe ₃ O ₄ or Fe ₂ O ₃ or the like.
In this cooling step, it is preferable to cool to 300 ° C. or lower, preferably 200 ° C. or lower, particularly preferably 150 ° C. or lower (usually 100 ° C. or higher) under the above conditions.

  In the above production method, in order to increase the recovery rate of FeO powder, it is preferable to use a granulated product containing metallic iron. The content of metallic iron is preferably 5% by mass or more, particularly preferably 5 to 85% by mass, more preferably 8 to 50% by mass, when the total amount of iron components contained in the granulated product is 100% by mass. %. Thereby, among the powders produced in this production method, the content of FeO powder converted based on the total amount of iron is 80% by mass or more, preferably 85% by mass or more, particularly preferably 90% by mass or more. Can do.

The following are mentioned as a raw material which comprises the above granulated products containing metallic iron. In addition, description of a binder etc. is abbreviate | omitted.
(1) Forged shot dust collection only,
(2) Mixture of forged shot dust collection waste and metallic iron (reducing agent) such as iron powder (3) Mixture of electric furnace dust and metallic iron (reducing agent) such as iron powder (4) Blast furnace dust and iron powder Mixture with metallic iron (reducing agent) such as (5) Converter dust only

Dust cleaning in the dust cleaning step is performed by washing with water. This washing method is not particularly limited. The chlorine component contained in the dust should be sufficiently dissolved and removed in the water at the time of washing with water, for example, a method of taking water and dust into a container and stirring, and then removing the dust from the container, Examples include a method in which water is continuously flowed into and out of a charged container. In consideration of the amount of water used and the removal efficiency of chlorine, a method of washing in the rotary of the rotary mixer truck is preferable.
The mass ratio between the dust and the cleaning water and the cleaning time in the dust cleaning step are not particularly limited.

The method for removing the washing water from the dust in the washing water removal step is not particularly limited, and examples thereof include water removal by filtration, filter press, and centrifugation. Among these, a method using a filter press is more preferable.
The chlorine content contained in the dust after the washing water removal step is preferably reduced to 0.5% by mass or less, particularly 0.4% by mass or less, and further to 0.3% by mass or less. More preferred. The dust having a low chlorine concentration is difficult to agglomerate during vacuum heating, thereby preventing the formation of a lump of dust. In addition, moisture may remain in the dust after the washing water removal step, and the remaining moisture can be effectively used in the granulation step. The upper limit of the residual moisture is preferably 20% by mass, particularly preferably 15% by mass, and more preferably 12% by mass when the dust after the washing water removing step is 100% by mass.

Furthermore, according to this method for producing FeO powder, iron-containing dust can be treated as a recycled material, and FeO powder can be produced in large quantities and efficiently. That is, by granulating the dust, uniform heating is performed by the excellent thermal conductivity of the granulated product, and the reaction during vacuum heating proceeds smoothly. Furthermore, FeO produced in the heating process is rapidly cooled under a predetermined pressure of vacuum, so that it can be recovered as it is without being oxidized. In other words, FeO can be recovered as FeO without being further oxidized to other oxidation states such as Fe ₃ O ₄ and Fe ₂ O ₃ . In addition, by including a reducing agent such as metallic iron in the granulated product, other metal components, for example, oxides such as zinc can be reduced and recovered as a single metal in the heating step.

[3] Plant Growth Promoter The ferrous oxide-containing composition of the present invention can be used as a plant growth promoter by blending a substance containing an iron chelating component, that is, a chelating substance. Examples of the chelating component of iron include fulvic acid and the like, and as the chelating substance containing fulvic acid or the like, humic soil, cow dung, chicken dung, compost, compost containing cow dung, etc. may be used. it can. As chelating substances, humic soil and cow dung, which are particularly excellent in promoting plant growth, are preferable. Only 1 type may be used for this chelating substance, and 2 or more types may be used for it.
When the plant growth promoter is 100% by mass, the total of the ferrous oxide-containing composition and the chelating substance is 85% by mass or more, particularly 90% by mass or more, and further 95% by mass or more (at 100% by mass). May be present). Moreover, when a plant growth promoter is used in the seedling stage, the total of the ferrous oxide-containing composition and the chelating agent is 0.1 to 5 masses when the plant growth promoter is 100 mass%. %, Particularly 0.5 to 5% by mass, more preferably 1 to 5% by mass. Furthermore, especially when used in the seedling raising stage, fertilization is applied to the plant very close to the seedling, so-called contact fertilization, so that iron can be supplied to the plant very efficiently.
In addition, when the sum total of a ferrous oxide containing composition and a chelating substance is 100 mass%, a ferrous oxide containing composition is 12-90 mass%, It is especially 50-90 mass%. preferable. If content of a ferrous oxide containing composition is 12-90 mass%, the growth of a plant can fully be accelerated | stimulated.

  The plant growth promoter may contain other inorganic components and metals. Examples of inorganic components include iron sesquioxide, iron tetroxide, manganese oxide, aluminum oxide, silicon oxide, magnesium oxide, titanium oxide, ferrite, calcium sulfate, calcium carbonate, calcium silicate, aluminum silicate, and antimony trioxide. . Examples of the metal include iron, manganese, zinc, nickel, copper, calcium, aluminum, molybdenum, and chromium. Moreover, the alloy which has 2 or more types of these metals, or another metal may be contained. Furthermore, carbon, boron, phosphorus, sulfur and the like may be contained. These inorganic components, metals, alloys and the like may be included alone or in combination of two or more. Furthermore, two or more of inorganic components, metals and alloys may be included. In addition, each shape, magnitude | size, etc. of an inorganic component, a metal, an alloy, etc. are not specifically limited.

  When the other components described above are contained, when the plant growth promoter is 100 parts by mass, the other components are preferably 15 parts by mass or less, particularly 5 parts by mass or less. Moreover, when other components are contained, the total content of the ferrous oxide-containing composition and the chelating substance in the plant growth promoter is the property of the medium using the plant growth promoter, the crop to be grown It can adjust suitably according to the kind of this.

The plant growth promoter can be used by mixing a ferrous oxide-containing composition and a chelating substance at the time of use. In addition, the ferrous oxide-containing composition and the chelating substance can be mixed in advance before use. When mixed and used before use, after mixing, use at a temperature of 5 to 35 ° C., particularly 15 to 30 ° C., for 24 to 480 hours, particularly after 168 to 240 hours, is sufficiently chelated or This is preferable because a state in which chelation is easy can be created.

  This plant growth promoter can sufficiently promote the growth of plants when used in ordinary agricultural land around pH 6.0 in Japan. In addition, when used in so-called alkaline soil, particularly alkaline lime soil having a pH exceeding 7.0 and not more than 11.0, particularly pH 7.5 to 11.0, and further pH 8.0 to 11.0, plant growth Can be promoted sufficiently. Furthermore, when this plant growth promoter is used in the seedling stage in alkaline soil, the total content of the ferrous oxide-containing composition and the chelating substance in the plant growth promoter is preferably within the above range. . In particular, when used in the seedling raising stage, even in alkaline soil, iron can be supplied to plants very efficiently by contact fertilization.

  The above alkaline soil is a soil whose pH exceeds 7 when 10 ml of air-dried soil is added with 25 ml of distilled water and shaken for 1 hour and the pH of the resulting suspension is measured. Say. Accordingly, the alkaline soil includes alkaline soil obtained by alkalizing the original alkaline soil and non-alkaline soil, for example, by fertilization or desertification. Examples of the above-mentioned basic alkaline soil include soil containing various calcareous components such as shell fossil soil, calcareous soil, and sandy soil. These may be used alone or in combination of two or more. Furthermore, a mixed soil of an alkaline soil containing these various calcareous components and a non-alkaline soil, which is an alkaline soil as a whole is also included.

  This plant growth promoter can be used for cultivation of various plants. For example, when used for rice, spinach, cabbage, Chinese cabbage, komatsuna, broccoli, cauliflower, radish, onions, carrots, peanuts, sweet potatoes, potatoes, watermelons, melons, etc., the effect of promoting growth is sufficiently exerted. .

  The amount of the plant growth promoter used is not particularly limited, and is preferably adjusted as appropriate according to the types of various plants that grow as described above, the types and amounts of fertilizer used together, the types of soil, the pH of the soil, and the like. In addition, it is preferable to appropriately adjust the contents of the FeO powder and the chelating substance in the plant growth promoter.

Hereinafter, the present invention will be specifically described by way of examples.
[1] Production of ferrous oxide-containing composition Example 1
Electric furnace dust was used as a raw material. In this electric furnace dust, Fe is 35.8% by mass, Zn is 22.7% by mass, C is 5.95% by mass, Ca is 2.92% by mass, Mn and Cl are 2.89% by mass, Si is 2.16 mass%, Pb is 1.48 mass%, and Cr is 1.24 mass%. The average particle size is 10 μm. This electric furnace dust 5 tons was washed for 1 hour using a tank charged with 10 tons of water. Thereafter, water was removed with a filter press to obtain a clay-like cake containing 20% by mass of water.

  The cake and the iron powder applied to a 1 mm mesh sieve are put into a mix muller so that the mass ratio of the electric furnace dust and iron powder contained in the cake is 1: 1, and then An alumina cement of 5% by mass of the dry mass of the furnace dust (the total of the dry mass of the electric furnace dust and the alumina cement is 100% by mass) was further added. Subsequently, this mixture was kneaded for 1 minute, and the water content was adjusted to 10% by mass and discharged. Thereafter, the discharged mixture was used to form a columnar granulated product having a diameter of 8 mm and a length of about 20 mm by a vertical extruder. Next, this granulated product was put in a drying furnace and dried at 400 ° C. for 60 minutes. 410 tons of this granulated product was continuously processed using the apparatus of FIG.

Hereafter, the manufacturing process of the ferrous oxide containing composition using the apparatus of FIG. 1 and this apparatus is demonstrated in detail.
The granulated product 4 was put into the hopper 11 of the material supply system 1 and replaced with a vacuum atmosphere, and then transferred to the vacuum heating furnace 21 of the vacuum heating system 2. This vacuum heating furnace 21 has four heating chambers 21, each stage is defined by a bottom 24, and a heater 25 for heating the granulated product 4 by radiant heat transfer is provided in each stage. In addition, an opening for dropping the granulated product 4 to the lower stage is provided at a predetermined position of the bottom 24. Further, a stirrer 23 is extended through the four-stage heating chamber of the vacuum heating furnace 21. The stirrer 23 includes a shaft 231, a rotary blade 232 attached to the shaft 231, a stirring member 233 disposed so as to extend from the rotary blade 232 toward the bottom 24 of the vacuum heating furnace 21, and a motor 234. Have. And the rotary blade 232 was continuously rotated by the rotational drive of the motor 234, and the granulated product 4 of the upper surface of the bottom part 24 of each stage was stirred. The internal pressure of the vacuum heating furnace 21 is set to 5.3 kPa by a vacuum pump, the heater 251 of the first heating chamber 211 from the top is set to 800 ° C., and the heater 252 of the second heating chamber 212 is set to 850 ° C. The temperatures of the heaters 253, 254, and 255 in the heating chamber 215 further below the third heating chamber 213, the fourth heating chamber 214, and the fourth heating chamber 214 were set to 900 ° C., respectively. .

  The granulated product 4 was adjusted by adjusting the rotation speed of the stirrer, stayed in each heating chamber with stirring for 30 minutes, and dropped sequentially into the lower heating chamber. Therefore, the granulated product was heated at 800 ° C. for 30 minutes, 850 ° C. for 30 minutes, and 900 ° C. for 1 hour. The granulated product gradually changed to powder by stirring.

  Thereafter, the powder produced as described above was discharged to the cooling system 26 by the discharge feeder 22 in a vacuum atmosphere connected to the vacuum heating furnace 21. Next, the powder was cooled in a cooling system 26 to 400 ° C. at a temperature decrease rate of 20 ° C./min in a vacuum atmosphere. Thereafter, the cooling system 26 was replaced with nitrogen gas, and the system was cooled to 200 ° C. at a temperature lowering rate of 13 ° C./min. The powder was then further cooled, discharged and collected. In addition, zinc was vaporized simultaneously by said heating, and it collect | recovered as metallic zinc.

[2] Evaluation of FeO powder (1) Evaluation of elements eluted from FeO powder 3 g of FeO powder was added to three types of pH adjusting solutions adjusted to pH 2.2, 4.2 or 5.0 with hydrochloric acid. After elapse of 264 hours, the aqueous solution was subjected to high frequency inductively coupled plasma optical emission spectrometry, and the eluted elements were quantified. The results are shown in Table 1.

  According to the results in Table 1, it can be seen that the elements eluted in a large amount are Ca and Al, and the amounts of Fe and Mg detected at the same time are very small. Since a large amount of Ca and Al are eluted in this way, it is estimated that the pH of the aqueous solution has increased.

(2) Change in pH of FeO powder and reagent FeO added to water and the presence or absence of red rust generation Prepare three types of pH adjustment solutions with pH adjusted to 2.2, 4.2 or 5.0 with hydrochloric acid. 3 g of FeO powder was added to 30 ml of each pH adjusting solution. In addition, 1 g of reagent FeO (powder) was added to each of three types of pH adjusting solutions adjusted in the same manner. The pH of these solutions was measured after 24 hours and after 96 hours. The results are shown in Table 2. In addition, about the FeO powder, the same measurement was repeated twice and each result was described in Table 2.

  According to the results of Table 2, the pH in the case of FeO powder is not greatly different depending on the pH of the pH adjusting solution after 24 hours and after 96 hours, and the pH after 24 hours is 11. The pH after passage of 0 to 11.3 and 96 hours is as high as 10.1 to 10.8. On the other hand, in the case of the reagent FeO, there is a slight difference in the pH of the solution depending on the pH of the pH adjusting solution, but the pH after lapse of 24 hours is 5.6 to 6.0, and the pH after 96 hours is 5.0 to 6 .2 and both are considerably lower than the case of FeO powder. This result supports the increase in pH of the liquid due to the elution of Ca and Al in (1) above.

  Further, for each of the FeO powder and the reagent FeO, the occurrence of red rust was observed visually after 24 hours and after 96 hours. As a result, in the FeO powder, no red rust was observed at all after 24 hours and after 96 hours regardless of the pH of the pH adjusting solution. On the other hand, with the reagent FeO, some red rust was already observed after 24 hours regardless of the pH of the pH adjusting solution, and red rust was observed over the entire surface after 96 hours. Considering these results together with the pH behavior of (2) above, it can be seen that the change of FeO to ferric hydroxide or the like is suppressed by increasing the pH of the liquid to become alkaline. Inferred.

(3) Evaluation by X-ray diffraction of FeO powder X-ray diffraction of the granulated product and FeO powder was measured. Further, the X-ray diffraction of the reagent FeO was also measured. The results are shown in FIGS.
According to FIGS. 2 and 3, the CaO diffraction peak in the granulated product disappears in the FeO powder, while the FeAl ₂ O ₄ diffraction peak not found in the granulated product is prominent in the FeO powder. In addition, diffraction peaks such as CaSi ₂ O ₅ and CaFeSi ₂ O ₆ are also observed. Thus, it can be seen that the FeO powder contains a composite oxide that was not found in the granulated product.
As shown in FIGS. 11 and 12, the FeO powder is added to the pH adjusting solution, and according to the X-ray diffraction of the FeO powder taken out after a predetermined time, the diffraction peak of CaFeSi ₂ O ₆ disappears. Yes. From this, Ca is eluted from the FeO powder, thereby increasing the pH and becoming alkaline, so that it is presumed that the change of FeO to ferric hydroxide or the like is suppressed, and red rust does not occur.

(4) Addition of FeO powder to the pH adjusting solution and change in pH when a long time has elapsed (no pH adjusting solution exchange)
Three kinds of pH adjusting liquids adjusted to pH 2.2, 4.2 or 5.0 with hydrochloric acid were prepared, and 3 g of FeO powder was added to 30 ml of each pH adjusting liquid. In addition, 1 g of reagent FeO (powder) was added to each of three types of pH adjusting solutions adjusted in the same manner. The pH of these solutions was measured after 1 day, 4 days, 6 days, 7 days, 8 days and 11 days. The result of FeO powder is shown in FIG. 4, and the result of reagent FeO is shown in FIG.

  According to FIG. 4, in the FeO powder, even when the pH adjustment solution having the lowest pH of 2.2 was used, the pH after lapse of 11 days was 8.7, and no red rust was generated. On the other hand, according to FIG. 5, with the reagent FeO, the pH after 11 days is 4.9 when using a pH adjusting solution of pH 2.2, and 6.2 when using a pH adjusting solution of pH 4.2. When the pH adjusting solution of pH 5.0 was used, it was 6.3, and red rust was generated after 4 days regardless of the pH of the pH adjusting solution.

(5) Change in pH when FeO powder is added to the pH adjusting solution for a long time (with pH adjusting solution replaced)
Three kinds of pH adjusting liquids adjusted to pH 2.2, 4.2 or 5.0 with hydrochloric acid were prepared, and 3 g of FeO powder was added to 30 ml of each pH adjusting liquid. In addition, after 4 days, 6 days, 12 days, and 14 days, the liquids were replaced with unused pH adjusting liquids adjusted to the respective pH values, and the pH values of these liquids were changed to 1, 4, 6, Measurements were made after 7 days, 8 days, 11 days, 12 days, 13 days, 14 days, 15 days, 18 days, 19 days, 20 days and 21 days. The results are shown in FIG.

  According to FIG. 6, when the pH adjusting solution having the lowest pH of 2.2 was used, the pH after 15 days was 3.8, and red rust was generated. On the other hand, when a pH adjustment solution of pH 4.2 and a pH adjustment solution of pH 5.0 are used, the pH rises relatively quickly, and in either case, red rust occurs regardless of the number of days elapsed. There wasn't.

(6) Evaluation by Scanning Electron Microscope (SEM) and Energy Dispersive X-ray Analysis (EDX) FeO powder was observed by SEM and measured by EDX. The same applies to the FeO powder taken out from the liquid after 21 days in the experimental example in which FeO powder was added to the pH adjustment liquid whose pH was adjusted to 2.2 in the above (5) and red rust was generated after 15 days. Were observed by SEM and measured by EDX. FIG. 7 is an explanatory diagram based on a photograph taken by observing the FeO powder with an SEM, and FIG. 8 is a measurement result of EDX of the FeO powder. FIG. 9 is an explanatory diagram based on a photograph in which FeO powder is dissolved in a pH adjusting solution and a portion where red rust is observed by SEM, and FIG. 10 is a diagram in which FeO powder is dissolved in a pH adjusting solution. It is a measurement result of EDX of the part which generated. FIG. 11 is an explanatory diagram based on a photograph in which FeO powder is dissolved in a pH adjusting solution, and a portion where red rust is not generated is observed with an SEM, and FIG. 12 is a diagram in which FeO powder is dissolved in a pH adjusting solution. It is a measurement result of EDX of a part where red rust did not occur.

  It can be seen from FIGS. 7 and 9 that the outer shape is clearly changed. Also, from FIGS. 8 and 10, FeO powder is added to the pH adjusting solution, and in the portion where red rust is generated, Ca, Al, etc. are reduced compared to the measurement results of FeO powder not treated at all. This is consistent with the result of the dissolution of Ca, Al, etc. in (1) above. 10 and 12 are compared, FIG. 10 shows that Ca, Al, etc. are a little smaller than FIG. 12, and the uneven distribution of Ca, Al, etc. affects the occurrence of red rust. Is inferred.

(7) Evaluation by X-ray diffraction of FeO powder after addition to pH adjusting solution Each of FeO powder and reagent FeO, and FeO powder are added to pH adjusting solution at pH 2.2 as in (4) above. The sample and FeO powder after the passage of day are added to the pH adjustment solution of pH 2.2 as in (5) above, and the sample and FeO powder after the passage of 21 days are added to the pH adjustment solution of pH 5.0 as in (5) above. The X-ray diffraction of each of the samples after addition and after 21 days was measured. The results are shown in FIG. Further, the reagent FeO is added to the pH adjusting solution having a pH of 2.2 as described in the above (4), the sample after 11 days and the reagent FeO are added to the pH adjusting solution having a pH of 5.0 as described in the above (4), The X-ray diffraction of each of the samples after 11 days was measured. The results are shown in FIG.

According to FIG. 13, in FeO powder, FeO is a main component, and the presence of Fe, FeAl ₂ O _4, CaAl ₂ O _{4 and the} like was also confirmed. On the other hand, according to FIG. 14, in the reagent FeO, FeO is the main component, and the presence of Fe, Fe ₃ O _4, Fe (OH) _3, etc. was also confirmed. Thus, it was confirmed that the FeO powder contains a specific composite oxide not contained in the reagent FeO.

[3] Action and effect of ferrous oxide-containing composition as plant growth promoter Experimental Example 1
FeO powder and humus (made by Ueda Forestry Co., Ltd., trade name “Kutsuki Bark”) were mixed at a mass ratio of 3: 1 to produce a plant growth promoter. Hereinafter, this is referred to as “soil-type growth promoter”. This soil type growth promoter was allowed to stand at a temperature of 25 to 35 ° C. for 240 hours and then subjected to a cultivation experiment.

Cultivation experiment 1
A sandy field in Shonan City, Aichi Prefecture was selected as the experimental site. A cultivation section of 1.2 × 30 m was determined in a field of about 10a in area, and 45 kg of the soil type growth promoter produced in Experimental Example 1 was evenly sprayed on the entire surface of the section, followed by curing for one week. Thereafter, a commercially available fertilizer was uniformly applied to the entire surface of the cultivation section so as to be N8 kg, P12 kg, and K8 kg per 10a, and cultivated. Next, cocoons were created and seedlings of radish (variety “Miyashige”) were planted in September. Harvesting took place in November.
As a control plot, radish seedlings were planted and harvested in the same manner except that the soil type growth promoter was not sprayed on the adjacent plots.

  The average size of each of the radish (total number is 65) harvested from the cultivation plot sprayed with the soil type growth promoter and the radish harvested from the control plot (total number is 65). Ten radishes were selected for each and the weight of each was measured. As a result, the average value of 10 radish harvested from the cultivation plot sprayed with the soil type growth promoter was about 3000 g. On the other hand, the average value of 10 radish harvested from the control group was about 600 g. Thus, the radish harvested from the cultivation section sprayed with the soil type growth promoter has about five times the weight of the radish harvested from the control zone, and the growth promotion is sufficiently performed by the soil type growth promoter. I understand.

Cultivation experiment 2
A 1.2 × 30m cultivation section is set up in a sandy field of about 10a in Shonan City, Aichi Prefecture, and 45 kg of the soil type growth promoter produced in Experimental Example 1 is evenly sprayed on the entire surface of the section and mixed. Cured for 1 week. Thereafter, the mashed lime was spread evenly over the entire surface of the cultivation section, and then compost and chemical fertilizer were equally applied to the entire surface of the cultivation section and cultivated. Then, in September, planted potato seedlings (variety “Digima”). Harvesting took place in December.
As a control plot, potato seedlings were planted and harvested in the same manner except that the soil type growth promoter was not sprayed on the adjacent plots.

  The average size of potato harvested from the cultivation plot sprayed with the soil type growth promoter (total number is 50) and potato harvested from the control plot (total 50). Ten potatoes were selected for each and weighed. As a result, the average value of 10 pieces of potato harvested from the cultivation section sprayed with the soil type growth promoter was about 135 g. On the other hand, in the potato harvested from the control plot, the average value of 10 pieces was about 100 g. Thus, the potato harvested from the cultivation section sprayed with the soil type growth promoter has a weight about 1.3 times that of the potato harvested from the control zone, and the growth is sufficiently promoted by the soil type growth promoter. I understand that.

Cultivation experiment 3
A 1.2 × 30m cultivation section is set up in a sandy field of about 10a in Shonan City, Aichi Prefecture, and 45 kg of the soil type growth promoter produced in Experimental Example 1 is evenly sprayed on the entire surface of the section and mixed. Cured for 1 week. Thereafter, the whole body of the cultivation section was spread with the dough lime uniformly in advance, and then commercially available fertilizer was uniformly applied to the entire surface of the cultivation section so that N, P, and K per 10a were 8 kg each, and cultivated. Then, in September, planted carrot seedlings (variety “Kureiro”). Harvesting took place on December 24 and on January 10 of the following year, 17 days later.
As a control plot, carrot seedlings were planted in the same manner except that the soil type growth promoter was not sprayed on adjacent plots, and harvested twice in the same manner.

Ginseng harvested from the cultivation plot sprayed with soil type growth promoter (total number of each at the time of two harvests is 50) and ginseng harvested from the control plot (total number of each at the time of two harvests is 50), 10 carrots having an average size were selected, and their weights were measured. As a result, in the carrot harvested from the cultivation section sprayed with the soil type growth promoter harvested on December 24, the average value of 10 was about 260 g. On the other hand, the average value of the carrots harvested from the control plot was about 170 g. In addition, when harvested on January 10, the average value of 10 ginsengs was about 350 g for the carrots harvested from the cultivation section sprayed with the soil type growth promoter. On the other hand, in the carrots harvested from the control plot, the average value of 10 was about 270 g. Thus, the carrots harvested from the cultivation section sprayed with the soil type growth promoter have a weight about 1.3 times that of the carrots harvested from the control section, and the growth is sufficiently promoted by the soil type growth promoter. I understand that.
In addition, the carrot harvested from the cultivation plot sprayed with the soil type growth promoter on December 24 has the same weight as the carrot harvested from the control plot 17 days later. It can be seen that the growth is sufficiently promoted by the accelerator.
Moreover, the result of the reference example which compared the carrot harvested from the cultivation plot by the other cultivation experiment implemented similarly and the carrot harvested from the control plot is shown in FIG. This FIG. 15 also reveals the action and effect of the growth promotion of the soil type growth promoter.

Cultivation experiment 4
Agricultural plots of 1.2 x 30 m are set on a clay field of approximately 10a in Aku-cho, Chita-gun, Aichi Prefecture, and 45 kg of the soil type growth promoter produced in Experimental Example 1 is evenly sprayed over the entire area. After mixing, it was cured for 1 week. Then, organic lime and mashed lime are spread evenly over the entire surface of the cultivation section in advance, and after one week, the straw and bean fertilizer are added to the cultivation section so that N4kg, P11kg, K15kg, Mg1kg and B0.1kg per 10a are obtained. The entire surface was evenly fertilized and cultivated. Then, in July, a sweet potato seedling (variety “Red East”) was planted. Harvesting took place in November.
As a control plot, a sweet potato seedling was planted and harvested in the same manner except that the soil type growth promoter was not sprayed on the adjacent plot.

  For each of the sweet potatoes harvested from the cultivation plot sprayed with the soil type growth promoter (total number is 120) and the sweet potatoes harvested from the control plot (total number is 120) Three sweet potatoes were selected, and the weight of each was measured. As a result, the average value of three pieces of the sweet potato harvested from the cultivation section sprayed with the soil type growth promoter was about 861 g. On the other hand, in the sweet potato harvested from the control plot, the average value of the three pieces was about 371 g. The sweet potato harvested from the cultivation section sprayed with the soil type growth promoter in this way has a weight about 2.3 times that of the sweet potato harvested from the control plot, and the growth promotion is sufficiently promoted by the soil type growth promoter. I understand that.

  Also, one of each of the average size of each sweet potato harvested from each of the cultivation section and the control section is selected, and the sugar content is determined by handy sugar content meter (manufactured by Shimadzu Corporation, model “AMY-1”). )). As a result, the sugar content of the sweet potato harvested from the cultivation section was 12.5, and the sugar content of the sweet potato harvested from the control section was 11.3. As described above, the sugar content of the sweet potato harvested from the cultivation section was about 1.11 times higher than that of the sweet potato harvested from the control section.

Cultivation experiment 5
Agricultural plots of 1.2 x 30 m are set on a clay field of approximately 10a in Aku-cho, Chita-gun, Aichi Prefecture, and 45 kg of the soil type growth promoter produced in Experimental Example 1 is evenly sprayed over the entire area. After mixing, it was cured for 1 week. Then, organic lime and mashed lime are spread evenly over the entire surface of the cultivation section in advance, and after one week, the straw and bean fertilizer are added to the cultivation section so that N4kg, P11kg, K15kg, Mg1kg and B0.1kg per 10a are obtained. The entire surface was evenly fertilized and cultivated. After that, seedlings of peanuts (variety “Sayaka”) were planted in May. Harvesting took place in October.
As a control plot, peanut seedlings were planted and harvested in the same manner except that the soil type growth promoter was not sprayed on the adjacent plots.

For each of the peanuts harvested from the cultivation plot sprayed with the soil type growth promoter (total number is 30) and the peanuts harvested from the control plot (total is 30), Ten strains of peanuts were selected, and the weights excluding leaves, roots and stems were measured. As a result, the average value of 10 strains was about 320 g in the peanuts harvested from the cultivation section sprayed with the soil type growth promoter. On the other hand, the average value of 10 strains of peanuts harvested from the control group was about 220 g. Thus, the peanuts harvested from the cultivation section sprayed with the soil type growth promoter has a weight about 1.45 times that of the peanuts harvested from the control section, and the growth is sufficiently promoted by the soil type growth promoter. I understand that.
Moreover, the result of the reference example which compared the peanut harvested from the cultivation plot by the other cultivation experiment implemented similarly and the peanut harvested from the control plot is shown in FIG. This FIG. 16 also reveals the action and effect of the growth promotion of the soil type growth promoter.

Cultivation experiment 6
A 0.7 × 20 m area is selected for the field (sandy soil) in the same place as the cultivation experiment 1, and 2.1 kg of the soil-type growth promoter produced in Experimental Example 1 in the 0.7 × 10 m section on the south side ( About 300 g / m ² ) and sprayed to obtain a cultivation section. Further, the soil type growth promoter was not sprayed on the 0.7 × 10 m section on the north side, and this section was used as a control section. Thereafter, in the cultivation section, soil and a soil type growth promoter were mixed and cured for one week. Next, a commercially available fertilizer was uniformly applied to the entire surface of the cultivation section so as to be N8 kg, P12 kg, and K8 kg per 10a, and cultivated. After that, cocoons were created in each of the cultivation section and the control section, and seeds of Chinese cabbage were planted in July. Harvesting took place on November 5th and on December 5th, one month later.

Chinese cabbage harvested from the cultivation section sprayed with the soil type growth promoter (total number of each at the time of two harvests is 20) and Chinese cabbage harvested from the control plot (the total number of each at the time of two harvests is For each of 20), three average size Chinese cabbages were selected and the weight of each was measured. As a result, in the Chinese cabbage harvested from the cultivation section sprayed with the soil type growth promoter harvested on November 5, the average value of three was about 1900 g. On the other hand, in the Chinese cabbage harvested from the control group, the average value of the three was about 800 g. In addition, when harvested on December 5, the average value of the three Chinese cabbages harvested from the cultivation section sprayed with the soil type growth promoter was about 2800 g. On the other hand, in the Chinese cabbage harvested from the control group, the average value of the three was about 1600 g. The Chinese cabbage harvested from the cultivation section sprayed with the soil type growth promoter in this manner has a weight about 1.7 to 2.4 times that of the Chinese cabbage harvested from the control section, and the growth is sufficiently promoted by the soil type growth promoter. It can be seen that
The Chinese cabbage harvested from the cultivation section sprayed with the soil type growth promoter on November 5 has a weight about 1.2 times that of the Chinese cabbage harvested from the control section one month later. It can be seen that the growth is sufficiently promoted by the soil type growth promoter.

In addition, from each of the Chinese cabbage harvested from each of the cultivation plot and the control plot, three samples each having approximately the same size are selected as samples, and a chlorophyll meter (model “SPAD-502”, manufactured by Minolta Co., Ltd.). Thus, the amount of chlorophyll was evaluated using the green density (SPAD value) as an index. As a result, when the soil type growth promoter was used, the average value of 3 was 38, whereas the average value of 3 was 33 in the control group. Thus, the amount of chlorophyll increased in the Chinese cabbage in the cultivation section using the plant growth promoter of the present invention.
Furthermore, the result of the reference example which compared the Chinese cabbage harvested from the cultivation plot by the other cultivation experiment implemented similarly and the Chinese cabbage harvested from the control plot is shown in FIG. Also in FIG. 17, the action and effect of the growth promotion of the soil type growth promoter are clear.

Cultivation experiment 7
Komatsuna was cultivated in the same manner as in the cultivation experiment 6 except that seeds of Komatsuna were sown in December and harvested on February 4.

  The average size of each of Komatsuna (26 total) harvested from the cultivation plot sprayed with the soil type growth promoter and the Komatsuna harvested from the control plot (26 total). Ten komatsuna were selected and the weight of each was measured. As a result, the average value of ten komatsuna harvested from the cultivation section sprayed with the soil type growth promoter was about 24 g. On the other hand, in the Komatsuna harvested from the control plot, the average value of 10 was about 19 g. The komatsuna harvested from the cultivation section sprayed with the soil type growth promoter in this way has a weight about 1.3 times that of the komatsuna harvested from the control section, and the growth is sufficiently promoted by the soil type growth promoter. I understand that. In addition, one sample each having the same size from each of the Komatsuna harvested from each of the cultivation section and the control section is selected as a sample, and the amount of chlorophyll is determined by the green concentration (as in the case of the cultivation experiment 6). SPAD value) was evaluated as an index. As a result, it was 40 when the soil type growth promoter was used, whereas it was 36 in the control group. Thus, the amount of chlorophyll increased in Komatsuna in the cultivation section using the plant growth promoter of the present invention.

Cultivation experiment 8
Spinach was cultivated in the same manner as in the cultivation experiment 6 except that seeds of spinach were planted in December and harvested on February 4.

  The average size of spinach harvested from the cultivation plot sprayed with the soil type growth promoter (total number is 20) and spinach harvested from the control plot (total number is 20). Six spinach were selected for each and the weight of each was measured. As a result, in the spinach harvested from the cultivation section sprayed with the soil type growth promoter, the average value of 6 was about 44 g. On the other hand, in the spinach harvested from the control plot, the average value of the six was about 30 g. Thus, spinach harvested from the cultivation section sprayed with the soil type growth promoter has a weight about 1.5 times that of the spinach harvested from the control zone, and the growth promotion is sufficiently promoted by the soil type growth promoter. I understand that. In addition, from the spinach harvested from each of the cultivation section and the control section, three samples of approximately the same size were selected as samples, and the amount of chlorophyll was determined as the green density (SPAD value) in the same manner as in the cultivation experiment 6. Was evaluated as an index. As a result, when the soil type growth promoter was used, the average value of the three was 38, while the average value of the three was 36 in the control group. Thus, the amount of chlorophyll increased in Komatsuna in the cultivation section using the plant growth promoter of the present invention.

Cultivation experiment 9
A 20 × 20 m area is selected in the same field as the cultivation experiment 1 (sandy soil), divided into two sections, east and west, and 15 kg (about 113 g / kg) of the soil type growth promoter produced in Experiment 1 in the east section. m ² equivalent) and sprayed, and this section was used as a cultivation section. In addition, a soil type growth promoter was not sprayed on the western section, and this section was used as a control section. Thereafter, commercially available fertilizer was evenly applied to the entire surface of each of the cultivation section and the control section so as to be N14 kg, P21 kg, and K18 kg per 10a, and cultivated. Next, in June, mussel melon seedlings were planted in each of the cultivation plot and the control plot. Then, in the middle of August, 10 melons were harvested from each of the cultivation section and the control section. Thereafter, one of the average size was selected from 10 melons, and the sugar content was measured in the same manner as described above. As a result, in the melon harvested from the cultivation section, the sugar content near the outer skin was 15.8, and the sugar content in the central part was 16.4. On the other hand, in the melon harvested from the control plot, the sugar content near the outer skin was 14.0, and the sugar content in the central part was 15.2. As described above, the melon harvested from the cultivation section had an improved sugar content of about 1.13 times in the vicinity of the outer skin and about 1.08 times in the center compared to the melon harvested from the control section.

Cultivation experiment 10
Broccoli (variety is a pixel) was cultivated with pot seedlings in Takamatsu City, Kagawa Prefecture. The seedlings were purchased from a seedling supplier on April 10. In the case of using cultivated soil in which 5 g of the soil type growth promoter produced in Experimental Example 1 is mixed per liter of commercially available seedling cultivated soil (Test Example 1), 10 g of cultivated soil was used as the cultivated soil. Whether or not there is a difference in the growth of broccoli was examined for the case (Test Example 2) and the case of using cultivated soil in which the soil type growth promoter was not mixed (Comparative Test Example). After planting the purchased seedlings in 5 pots for each of Test Example 1, Test Example 2 and Comparative Test Example for one month, weighed the fresh weight of the aerial part of 15 pots of broccoli. However, Test Example 1 is 10.7 g, Test Example 2 is 22.0 g, and Comparative Test Example is 9.4 g. Test Example 1 is 1.1 times larger than Comparative Test Example. It increased 2.4 times from the test example. Moreover, when the dry weight of the root was measured, the average value was 5.1 g in Test Example 1, 6.2 g in Test Example 2, and 4.6 g in Comparative Test Example. It increased 1 time, and in Test Example 2, it increased 1.4 times compared with the Comparative Test Example. Thus, it was confirmed that the plant growth promoter of the present invention increased the roots, and as a result, the plant growth was promoted.

Cultivation experiment 11
In Takamatsu City, Kagawa Prefecture, 130 g of paddy rice seeds were sown and planted on a commercial rice planting seedling tray on June 10, and planted on July 1. This paddy field is clayey and pre-applied with commercially available fertilizer on June 3 so as to be N8 kg, P12 kg and K8 kg per 10a. Also, 3.3 m × 9.6 m sections were provided for each of the test section and the comparative test section, and about 540 seedlings were planted in each section. Planted in such a way.) At the time of planting, 15 g of a soil type growth promoter was mixed in the test plot so as to directly contact the seedling roots.
On July 21st, the growth status was confirmed on 270 seedlings in total, 45 in each of the test plots and the comparative test plots. As a result, the number of tillers of the seedling bundles was 14 in the comparative test group, whereas the number of tillers was increased to 17 in the test group. Also, the leaf length of the seedlings was 36 cm in the comparative test group, whereas it was 39 cm in the test group, which was larger.

Cultivation experiment 12
A field test was conducted to investigate the growth of paddy rice in alkaline soil. In the test, soil in which NPK was administered to Kokuboku soil representing Japanese soil (pH 6.4; Kokuboku Soil District), soil in which calcareous alkaline soil was contact-coated with NPK-only coated fertilizer containing no trace elements (pH 9). .3; Long treatment zone), soil obtained by contact fertilization with NPK and a trace fertilizer containing trace elements on calcareous alkaline soil (pH 9.3; Long Total treatment zone), soil type growth promotion produced in Experimental Example 1 in calcareous alkaline soil The test was carried out in triplicate in 1 section with soil containing the agent (pH 9.3; seedling box treatment section).
As a result of conducting the field test as described above,
When the rice cultivar is “Moonlight”, the number of spikes is 268 / m ² in the Kuroboku soil area, 0 in the Long treatment area, 254 / m ² in the Long Total treatment area, and 254 / m ^{2 in} the Nursery treatment area. 302 pieces / m ² . The number of pods per spike was 89.8 in the Kuroboku soil, 0 in the Long treatment, 65.7 in the Long Total treatment, and 90.3 in the seedling treatment. The yield per 10a was 545.8 kg in the Kuroboku soil section, 0 kg in the Long treatment section, 368.7 kg in the Long Total treatment section, and 592.4 kg in the seedling box treatment section.
If rice cultivars is "Sasanishiki", panicle number, 321 present ^/ m 2, in Long treatment group 0 present ^/ m 2, Long Total treatment group at 331 / ^{m 2,} seedling box treatment group with Andosol Zone It was in 463 present / ^{m 2.} The number of pods per spike was 81.6 in the Kuroboku soil, 0 in the Long treatment, 68.1 in the Long Total treatment, and 88.1 in the seedling treatment. The yield per 10a was 529.3 kg in the Kuroboku soil section, 0 kg in the Long treatment section, 467.9 kg in the Long Total treatment section, and 729.2 kg in the seedling box treatment section.
As described above, no paddy rice grew at all in the Long treatment section to which iron as a trace element was not applied. In addition, while the growth of paddy rice was observed in the Long Total treatment group, the number and yield of pods per ear were considerably inferior to those of the Kuroboku soil area. On the other hand, in the seedling box treatment area containing the soil type growth promoter, the number of spikes, the number of pods per spike and the yield per 10a are all significantly higher than those of the Kuroboku soil area, although there are some differences depending on the variety of rice. And growth was promoted.

  In addition, this invention is not limited to said Example, It can be set as the Example variously changed within the range of this invention according to the objective, a use, etc. For example, the dust cake and the reducing agent can be mixed by using a mixer such as an Eirich backflow type high-speed mixer. In addition, according to this plant growth promoter, since divalent iron ions are continuously supplied directly to plant root cells even under alkaline soil conditions, the plant growth promoter is directly applied to paddy rice in a calcareous alkaline soil paddy field. When fertilized, the effect of increasing the greenness of the leaves from the initial growth stage is exhibited. Furthermore, the plant growth promoter is used by being applied to the soil, and not only is the plant taking up divalent iron ions from the roots in the underground part, but in particular, the plant growth promoter is immersed in water and eluted. Even when a liquid mainly composed of divalent iron ions is used as an iron-based foliar spray agent for fruit trees and flower buds, divalent iron ions can be directly absorbed into cells from above-ground tissues. The effect and effect of promoting growth are exhibited in the same manner as when iron ions are taken from the part.

Claims (5)

Ferrous oxide, CaAl ₂ O ₄ , FeAl ₂ O ₄ , MgAl ₂ O ₄ , CaFeSi ₂ O ₆ , MgFeSi ₂ O ₆ , CaSi ₂ O ₅ , MgSi ₂ O ₅ , CaFe ₂ O ₄ , MgFe ₂ O ₄ And a ferrous oxide-containing composition for promoting plant growth, comprising at least one complex oxide of CaFeO ₂ and MgFeO ₂ . _2. The ferrous oxide-containing composition for promoting plant growth according to claim 1, wherein the composite oxide is CaAl ₂ O ₄ and FeAl ₂ O ₄ . When the ferrous oxide-containing composition for promoting plant growth is 100 parts by mass, the total of the ferrous oxide and the composite oxide is 65 parts by mass or more, and the ferrous oxide is 58 parts by mass. The ferrous oxide-containing composition for promoting plant growth according to claim 2 , wherein 0.5 to 99.5 parts by mass and the composite oxide is 0.325 to 10 parts by mass. The ferrous oxide-containing composition for promoting plant growth was added to a hydrochloric acid aqueous solution having a hydrogen ion index of 2.2 so that the mass ratio was 10% by mass, and the hydrogen ion index measured after 24 hours was 8.0 to 8.0. 12.0, a and hydrogen ion exponent measured after 264 hours 7.5 to 11.0, claim 3 that divalent iron ions are precipitated in a ferric hydroxide is suppressed A ferrous oxide-containing composition for promoting plant growth according to 1. Al and Ca contained in an aqueous solution prepared by adding the ferrous oxide-containing composition for promoting plant growth to a mass ratio of 10% by mass to an aqueous hydrochloric acid solution having a hydrogen ion index of 2.2 for 264 hours. The ferrous oxide-containing composition for promoting plant growth according to claim 4 , wherein the Al content is 70 to 130 mg / liter and the Ca content is 90 to 170 mg / liter when quantitatively determined later.