JP2007105036A - Granular material for agricultural soil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain inexpensive agricultural soil containing dredged earth and sand such as sedimented earth and sand in lakes and marshes, and excellent in chemical, physical and biological properties. <P>SOLUTION: A granular material for agricultural soil is obtained by homogeneously kneading clayey dredged earth and sand consisting of those at the bottom of natural or artificial lakes and marshes with a material incorporated with a predetermined amount of the powdery carbonized product of phytobiomass obtained from the surrounding area and/or downstream area of the above lakes and marshes and then granulating the kneaded product. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a granular material for agricultural soil containing dredged sand from a lake and a method for improving agricultural soil using dredged sand from a lake.

Eutrophication in public waters such as lakes is a serious problem. This eutrophication is thought to occur when minerals such as nitrogen and phosphorus flow out into the water from the sediment deposited on the bottom of the lake and the plactone grows abnormally.
Furthermore, the decrease in the amount of artificial lake water storage caused by the sediment deposited on the bottom of the dam (artificial lake) and the deterioration of the functions of the discharge pipes and drainage pipes of the artificial lakes are also problems.

  Thus, in order to solve these problems, conventionally, dredging of sediments in lakes and marshes has been performed. However, dredged sediment has often been discarded without being effectively utilized.

  Under these circumstances, with increasing demand for environmental protection and cost reduction in recent years, the effective use of dredged soil without discarding has attracted attention, and various attempts have been made.

For example, Patent Document 1 discloses a method for improving agricultural soil, characterized in that sedimentary soil from artificial lakes and marshes is mixed with cultivated soil in a field and fertilized with compost or the like.
According to this improved method, first, the sediments of the artificial lakes and marshes containing various types of minerals in a well-balanced manner are mixed with the cultivated soil in the fields, so that various types of minerals can be given to the cultivated soil in the fields in a well-balanced manner. Next, an organic fertilizer component can be provided by applying compost or the like to the mixed farmland. Therefore, according to this improvement method, the cultivated soil in the field can be improved to agricultural soil containing a wide variety of minerals in a well-balanced manner and also containing an organic fertilizer component.
JP-A-10-276524

However, since sedimentary earth and sand, for example, water-soluble minerals such as potash and magnesium are eluted in water, the content of the water-soluble minerals is insufficient. In addition, dredged soil is usually acidic due to the influence of acid rain and the like, and is not suitable for agricultural soil (inferior in chemical properties).
In addition, sedimentary earth and sand are generally silt and clay and therefore have poor air permeability and water permeability (inferior in physical properties).
Furthermore, as described above, sedimentary soil is poor in air permeability, so that useful microorganisms (aerobic microorganisms) in the soil hardly grow (inferior in biological properties).

  For this reason, in order to use the agricultural soil of patent document 1 suitably for agriculture etc., in order to supplement the chemical property, physical property, and biological property, it is necessary to fertilize a lot of compost etc., and in terms of cost The burden was great.

  Accordingly, an object of the present invention is to provide an inexpensive agricultural soil that includes dredged soil such as sedimentary sediment of lakes and marshes, and has excellent chemical properties, physical properties, and biological properties.

  The present inventors have intensively studied to achieve the above-described object. As a result, for example, it has been found that by adding carbides of plant biomass such as driftwood and rice husk to dredged sediments of lake sediments, inexpensive agricultural soils with excellent chemical, physical, and biological properties can be produced. The invention has been completed.

  More specifically, the present invention provides the following.

  (1) A covered amount obtained by adding a predetermined amount of powdered carbide of plant biomass obtained from the surrounding area and / or downstream area of the lake to clayey dredged sand from which natural or artificial lake sediment has been dredged. Agricultural soil granular material in which additives are uniformly kneaded and granulated.

First, by adding a predetermined amount of plant biomass charcoal to dredged soil, the content of water-soluble minerals that tend to be deficient in dredged soil, such as potash, magnesium, calcium (lime), etc., is used for agricultural soil. Can be appropriate. Moreover, since the carbide of plant biomass is usually neutral or weakly alkaline, pH can be made appropriate for agricultural soil by adding plant biomass to dredged soil (the chemical property is improved). .
Moreover, when the porosity of the carbide adsorbs moisture, the water retention of the soil is improved, and at the same time, the water permeability can be improved (physical properties are improved).
Plant-based biomass is an inexpensive one that can be obtained almost free of charge.

  Since dredged clay is clayey, the ratio of gas phase and liquid phase is small and water permeability is low. However, since the structure is changed from a single grain structure to a aggregate structure by granulating the additive, the ratio of the gas phase and the liquid phase is increased, and the water permeability can be improved ( Improve physical properties). Since dredged sand is clayey, it can be easily granulated, for example, by heating, for example, by heating the one to which moisture is adsorbed by adding powdered carbide.

  Plant biomass charcoal has a porous structure and is a breeding base for useful microorganisms. In addition, organic matter does not exist in the pores, and carbides are neutral to weakly alkaline, so in this additive, rot fungi (fungi that grow on dead organisms and excreta) are less likely to grow. , Photosynthesizable bacteria and the like (useful microorganisms) are likely to grow. For this reason, the environment suitable for growth of a useful microorganism can be given by adding the carbide of plant biomass (biology improves).

  Moreover, according to invention of (1), what was obtained from the surrounding area and / or downstream area of a lake is used for plant biomass. For this reason, it is possible to carry out an industry that promotes the creation of a recycling-oriented society in the whole region through the securing of material circulation and the suppression of consumption of natural resources, etc., integrated with agriculture and forestry in surrounding areas of lakes, etc. The cost of transporting biomass can be reduced.

  Therefore, according to the invention of (1), it is possible to provide inexpensive agricultural soil that contains dredged sand and is excellent in chemical properties, physical properties, and biological properties.

The clay is a property containing a large amount of clay and silt so that it can be easily granulated by heating.
The dredged material sand refers to a material in which sediment deposited on the bottom of an artificial or natural lake is dredged.
Plant biomass includes, for example, driftwood, bark, organic waste (eg, fallen leaves, twigs, grass, etc.), wood construction waste, street tree pruning material, wood-processed wood waste (eg, thinned wood, sawdust, chips, mill ends) This refers to woody biomass, etc., and agricultural waste such as rice husk, rice straw, wheat straw, and bagasse.
The powdered carbide refers to a carbide having a particle size that does not prevent granulation of the granular material for agricultural soil having the particle size distribution having the above effect. The particle size of the powdered carbide is not particularly limited. Generally, if the sieve path of 4 mesh (aperture 4.75 mm) described in JIS Z 8801 is 80% by mass or more, a particle size distribution having excellent physical properties. It is considered that the particle size is such that it does not hinder granulation of the agricultural soil granulate. Depending on the size of the carbide, it may be made into powdered carbide by pulverization or the like, if necessary.

  Predetermined amount refers to the amount to which powdered carbides need to be added in order for the content of minerals such as potash, magnesium, lime, etc. to be appropriate for agricultural soil, and the types of dredged sand and plant biomass It may be appropriately selected depending on the composition and the like.

The surrounding area refers to the mountains in and around the lake.
The downstream area refers to the river basin flowing from the lake.

  (2) Plants obtained from the surrounding area and / or the downstream area of the lake into a granulated product obtained by granulating clay-dried dredged dredged sand from natural or artificial lake sediment Agricultural soil granulate obtained by uniformly kneading an additive to which a predetermined amount of powdered carbide of biomass is added.

  According to the invention of (2), first, dried dredged clay is used. For this reason, it is possible to perform granulation before kneading, not after kneading with a plant-based carbide having a moisture adsorption action as in (1).

  According to the invention of (2), since it is not different from the component of (1), the same effect as (1) can be obtained.

  Drying refers to removing moisture from dredged soil with a very high moisture content to the extent that it can be granulated. The drying method used in the present invention is not particularly limited, and examples thereof include a method of standing in a covered storage place and naturally drying for about one year while avoiding wetting of sediment due to rainfall. be able to.

  (3) The granular material for agricultural soil according to (1) or (2), wherein the plant biomass is woody biomass and / or agricultural waste.

  (4) The granular material for agricultural soil according to (3), wherein the woody biomass is driftwood obtained from the lake and the agricultural waste is rice husk obtained from a rice farm in the downstream area of the lake. .

  Since driftwood impairs the function of, for example, a water discharge facility for an artificial lake, it is necessary to remove the driftwood in order to maintain the artificial lake facility. However, since the removed driftwood has not been effectively used and most of it has been discarded or incinerated, it has been a problem in terms of environmental load and cost. According to the invention of (4), in addition to the effect obtained by the invention of (3), an artificial lake facility can be maintained while avoiding environmental burdens and cost burdens. The powdered carbide of driftwood is porous and alkaline, and is rich in air permeability and water retention, so it can be used as a soil conditioner.

  Rice husks that are discharged in large quantities by rice husks have not been used effectively, and most of them have been discarded and incinerated, so the burden on the environment (incineration of rice husks causes carbon dioxide emissions) and It was a problem in terms of cost. According to the invention of (4), in addition to the effect obtained by the invention of (3), it is possible to avoid an environmental load and a cost burden.

  (5) Agricultural soil granule according to any one of (1) to (4), wherein the additive is added with a predetermined amount of compost or organic fertilizer containing nitrogen and phosphorus before the granulation. object.

  According to the invention of (5), a predetermined amount of compost or organic fertilizer containing nitrogen and phosphorus is further added to the agricultural soil granular materials of (1) to (4). For this reason, according to the invention of (5), in addition to the effects obtained from the agricultural soil particulate matter of (1) to (4), the contents of nitrogen and phosphorus are appropriate for agricultural soil (due to the chemical nature) Furthermore, it is possible to provide agricultural soil.

  Predetermined amount refers to the amount to which powdered carbides need to be added in order for the nitrogen and phosphorus content to be appropriate for agricultural soil, including dredged sand, plant biomass, compost or organic fertilizer What is necessary is just to select suitably according to a kind, a composition, etc.

  (6) 60 mass parts of clayey dredged sand from which the bottom sediment of natural or artificial lakes is dredged, (A) 5-25 parts by mass of powdered carbides of driftwood obtained from the lakes, (B) the lakes 5-25 parts by weight of dust compost obtained by fermenting organic dust obtained from a nearby hydropower station intake, etc. (C) Chips and cows obtained by fragmenting driftwood obtained from the lake 5 to 25 parts by mass of cow manure compost obtained by fermenting a mixture obtained by mixing the feces and urine of the above (however, the total of (A), (B), and (C) additives is 40 parts by mass) A granular material for agricultural soil, which is obtained by uniformly kneading and granulating an additive to which is added.

  (7) In 60 parts by mass of clayey dredged sand in which the bottom sediment of natural or artificial lakes is dredged, (A) 5-25 parts by mass of powdered carbides of driftwood obtained from the lakes, (B) the lakes 15 to 35 parts by weight of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by shredding driftwood obtained from the above and cow manure (however, (A) and (B The total amount of the additives to be added) is a granulated product for agricultural soil, which is obtained by uniformly kneading and granulating the additives to which (a) is added.

  (8) Fermenting organic dust obtained from intakes of hydroelectric power stations near the lake with (A) 60 parts by mass of clay-type dredged sand from which natural or artificial lake sediment has been dredged 5 to 35 parts by weight of obtained compost, (B) 5 to 5 parts of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by fragmenting driftwood obtained from the lake and cow manure Agricultural soil for which 35 parts by mass, where (A) and (B) the total additive is 40 parts by mass) are uniformly kneaded and granulated Granules.

  (9) The driftwood powder obtained from the lake (A) in 60 parts by mass of the granulated material obtained by granulating the clay-dried dredged clay soil from which the sediment of natural or artificial lakes has been dredged 5-25 parts by mass of carbonized carbide, (B) 5-25 parts by mass of dust compost obtained by fermenting organic waste obtained from a hydroelectric power plant intake near the lake, and (C) obtained from the lake 5 to 25 parts by weight of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by fragmenting the obtained driftwood and cow manure (however, (A), (B), and (C) The total amount of additives to be added is 40 parts by mass) and the additives to which the additives are added are uniformly kneaded.

  (10) (A) Driftwood powder obtained from the lake, in 60 parts by mass of the granulated material obtained by granulating clay-dried dredged clay soil from which the sediment of natural or artificial lakes has been dredged 5 to 25 parts by mass of carbonized carbide, (B) 15 to 35 mass of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by fragmenting driftwood obtained from the lake and cattle manure Agricultural soil granulate obtained by uniformly kneading the additive to which the additive is added (however, the sum of the additives in (A) and (B) is 40 parts by mass).

  (11) A hydroelectric power plant intake near the lake (A) in 60 parts by mass of granulated dried granulated clay sand from which natural or artificial lake sediment has been dredged 5 to 35 parts by weight of dust compost obtained by fermenting organic dust obtained from, etc., (B) Mixing chips obtained by fragmenting driftwood obtained from the lake and cattle manure An additive to which 5 to 35 parts by weight of cow manure compost obtained by fermenting the obtained mixture (however, the sum of the additives of (A) and (B) is 40 parts by weight) is added. Agricultural soil granules that are uniformly kneaded.

  In the inventions of (6) to (8) and (9) to (11), a predetermined amount of dredged sand or a predetermined amount of dried dredging is produced when producing the granular material for agricultural soil. Dust compost obtained by fermenting powdered carbide of driftwood obtained from lakes, organic dust obtained from intakes of nearby hydroelectric power plants, etc. to be added to the granulated material with earth and sand granulated, And the addition ratio of the cow manure compost obtained by fermenting the mixture obtained by mixing the chip | tip obtained by fragmenting the driftwood obtained from the lake and cow manure is prescribed | regulated.

  As in the inventions shown in (6) to (8), a predetermined amount of dredged clay is uniformly kneaded with an additive to which powdered carbides of charcoal, dust compost, and cow manure compost are added at the above-mentioned addition ratio. By being granulated, it is possible to provide agricultural soil that is superior in chemical properties, physical properties, and biological properties.

  In addition, as in the inventions shown in (9) to (11), a powdered carbide, drift compost, and cow manure compost of driftwood are added to a granulated product obtained by granulating a predetermined amount of dried dredged soil. By uniformly kneading the additive to be added at the above-mentioned addition ratio, it is possible to provide agricultural soil that is superior in chemical properties, physical properties, and biological properties.

  Here, the hydroelectric power plant near the lake refers to the hydroelectric power plant installed near the lake. Hydropower station intakes and the like refer to intakes that take in water used in hydropower stations, sand basins that sink sand in the water, and water tanks, but are not limited to these. The facility is not particularly limited as long as it is an equipment that can be provided in a place and can obtain organic dust. Organic litter obtained from intakes of hydroelectric power plants near lakes refers to organic garbage that has been generated from forests such as deciduous leaves, twigs, and grass and spilled into the lakes. Dust compost refers to compost obtained by decomposing organic dust by microorganisms such as fungi and bacteria, protozoa such as Paramecium, and the like. That is, dust compost refers to compost obtained by fermenting organic dust. Dust compost has the effect of improving the chemical and physical properties of the soil.

  The chip obtained by fragmenting the driftwood obtained from the lake is obtained by fragmenting the driftwood obtained from the lake. The type of driftwood that can be a chip, the size of the chip, the shape of the chip, and the like are not particularly limited as long as they can be composted by fermenting a mixture obtained by mixing the chip and cattle manure. Cow manure compost refers to compost obtained by decomposing a mixture obtained by mixing chips and cattle manure with microorganisms such as fungi and bacteria, protozoa such as Paramecium, and the like. That is, cow manure compost refers to compost obtained by fermenting a mixture obtained by mixing chips and cow manure. Cow manure compost has the effect of improving fertilizer effects and improving the chemical and physical properties of the soil.

  According to the invention of (6) or (9), the powdered carbide of driftwood obtained from the lake (A) is added to 60 parts by mass of granulated material obtained by granulating dredged sand or dried dredged sand. 5-25 parts by mass, (B) 5-25 parts by mass of dust compost obtained by fermenting organic waste obtained from a hydroelectric power plant intake near the lake, and (C) obtained from the lake 5-25 parts by weight of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by fragmenting driftwood and cow manure (however, (A), (B), and (C It is preferable that a total of 40) parts to be added is added. When the added amount of powdered carbide of driftwood is less than 5 parts by mass, the chemical properties, physical properties and biological properties are not improved, and when it exceeds 25 parts by mass, no further effect can be obtained. When the added amount of dust compost is less than 5 parts by mass, the chemical properties and physical properties are not improved, and when it exceeds 25 parts by mass, no further effect can be obtained. When the addition amount of cow manure compost is less than 5 parts by mass, no fertilizer effect can be obtained, and when it exceeds 25 parts by mass, no further effect can be obtained.

  According to the invention of (7) or (10), the powdered carbide of driftwood obtained from the lake (A) on 60 parts by mass of granulated material obtained by granulating dredged sand or dried dredged sand 5 to 25 parts by weight, (B) 15 to 35 parts by weight of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by fragmenting driftwood obtained from the lake and cow manure, (However, (A) and (B) the total of the additives to be added is 40 parts by mass), and the granulated granulated granulated sand or dried dredged sand To 60 parts by mass of the product, (A) 10-20 parts by mass of powdered carbide of driftwood obtained from the lake, (B) chips obtained by fragmenting the driftwood obtained from the lake, and cow manure 20-30 parts by weight of cow manure compost obtained by fermenting a mixture obtained by mixing (however, (A) and (B) additives) The total is more preferably added in a) is 40 parts by mass. In this invention, when the addition amount of cow manure compost is less than 15 mass parts, a fertilizer effect is not produced so much, and when it exceeds 35 mass parts, enrichment of soil organic matter is caused.

  According to the invention of (8) or (11), to 60 parts by mass of granulated material in which dredged sand or dried dredged sand is granulated, (A) from a hydroelectric power plant intake near the lake, etc. 5 to 35 parts by weight of dust compost obtained by fermenting the obtained organic dust, (B) obtained by mixing chips obtained by fragmenting driftwood obtained from the lake and cattle manure It is preferable to add 5 to 35 parts by weight of cattle manure compost obtained by fermenting the mixture (however, the sum of the additives of (A) and (B) is 40 parts by weight). Or, compost obtained by fermenting 60 parts by mass of granulated material obtained by granulating dried dredged soil and sand (A) Organic dust obtained from the intake of a hydroelectric power plant near the lake 10-30 parts by mass, (B) Mixing obtained by mixing chips obtained by fragmenting driftwood obtained from the lake and cattle manure It is more preferable to add 10-30 parts by weight of cow manure compost obtained by fermenting (however, the total of the additives (A) and (B) is 40 parts by weight). Or, compost obtained by fermenting 60 parts by mass of granulated material obtained by granulating dried dredged soil and sand (A) Organic dust obtained from the intake of a hydroelectric power plant near the lake 20 parts by mass, (B) 20 parts by mass of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by fragmenting driftwood obtained from the lakes and cow manure Is more preferable. In the present invention, when the amount of dust compost added exceeds 35 parts by mass, since the proportion of cow manure compost is small, no fertilizer effect is achieved.

  (12) The granular material for agricultural soil according to any one of (1) to (11), wherein a sieve path having an opening of 15 mm described in JIS G 3553 is 80% by mass or more.

  In order to give excellent physical properties, it is preferable that the granular material for agricultural soil has a particle size distribution such that the sieve path with an opening of 15 mm described in JIS G 3553 is 80% by mass or more. In addition, in order to select the granular material for agricultural soils described in (12), it is necessary to classify the granulated material according to the intended use.

  (13) A continuous crop failure reducing material comprising the granular material for agricultural soil according to any one of (1) to (12) as a main component.

  Plant biomass charcoal has a porous structure and is a breeding base for useful microorganisms. For this reason, since the granulated product for agricultural soils (1) to (12) to which plant biomass is added has an environment suitable for the growth of useful microorganisms, it is difficult for disease-causing fungi and the like to propagate. Therefore, according to the invention of (13), continuous cropping trouble can be reduced.

  (14) Agricultural soil improvement material mainly composed of powdered carbides of driftwood and / or rice husk.

  According to the invention of (14), the content of minerals such as potash, magnesium and lime in agricultural soil can be made appropriate for agricultural soil (chemical properties are improved).

  “Containing as a main component” means that other components may be contained as long as the effects obtained by the inventions of (13) and (14) are not lost.

  (15) A granulated product obtained by granulating clay-dried dredged dredged soil from which natural or artificial lake sediment has been dredged, and a plant obtained from the surrounding area and / or downstream area of the lake Agricultural soil improvement method that uses powdered carbide of biomass based as agricultural soil in the downstream area of the lake.

  Since earth and sand, driftwood, etc. carried from the upstream stay in the lake, there is a tendency that this earth and sand, driftwood, etc. do not flow easily in the downstream area. As a result, the soil in the downstream area becomes deficient in nutrient components.

  According to the invention of (15), agricultural soil that is excellent in chemical properties, physical properties, and biological properties obtained from a lake and is inexpensive and is used as agricultural soil in the downstream area of the lake. For this reason, it is possible to improve the soil in the downstream area of the lake where nutrient components tend to be deficient.

  Moreover, according to the invention of (15), since the environmental load to the downstream area accompanying the installation of the artificial lake can be reduced, agriculture that is the same as before the artificial lake installation can be performed. For this reason, it is advantageous in that it is possible to prevent obsession with the residents in the downstream area when installing artificial lakes.

  According to the present invention, the following effects can be obtained.

  Since a predetermined amount of plant biomass charcoal is added to dredged soil, the content of minerals such as potash, magnesium, lime, etc. can be made appropriate for agricultural soil (chemical properties are improved). Moreover, since the structure is changed from a single grain structure to a aggregate structure by granulation, water permeability can be improved (physical properties are improved). An environment suitable for the growth of useful microorganisms can be provided by adding the carbide of plant-based biomass that serves as a breeding base for useful microorganisms (the biological property is improved). Furthermore, because plant-based biomass was obtained from the surrounding area of the lake and / or the downstream area, it is possible to carry out the local industry that is integrated with the agriculture and forestry of the lake and the surrounding area. At the same time, the cost of transporting the plant biomass can be reduced.

  Therefore, it is possible to provide inexpensive agricultural soil that includes dredged sand from lakes and has excellent chemical properties, physical properties, and biological properties.

  The granular material for agricultural soil of the present invention is a powdered carbide of plant-based biomass obtained from a peripheral region and / or a downstream region of the lake to clay-like dredged soil in which the bottom soil of natural or artificial lake is dredged Can be obtained by adding a predetermined amount. Hereinafter, an example of an embodiment of the present invention will be specifically described. FIG. 1 is a diagram showing the flow of this embodiment.

<Adjustment of dredged soil>
It is preferable to reduce the volume of dredged soil from which natural or artificial lake sediment has been dredged from the viewpoint of operability. The volume reduction method is not particularly limited, and examples thereof include use of a dehydration processing machine, sun drying, and solidification treatment.

  The dredged dredged sand can also be sieved to sort out trash (eg, vinyl, cans, etc.), stones, and the like. An apparatus used for this selection is not particularly limited, but normally, “Power Track 600 (trade name)” (manufactured by Power Screen Co., Ltd.) and the like can be mentioned.

<Adjustment of powdered carbide of plant biomass>
[Carbonization of plant biomass]
Although carbonization of plant biomass is not particularly limited, it is usually carried out by burning at 400 ° C. to 500 ° C. for about 1 day to 3 days. However, the carbonization conditions described above vary depending on the composition and amount of the plant-based biomass used, and can be appropriately selected.

[Powdering of plant biomass charcoal]
The plant-based biomass carbide needs to have a particle size distribution such that, for example, by pulverizing the carbide, a granulated product having excellent physical properties can be obtained through a granulation step described later. Such a particle size distribution is not particularly limited, but, for example, a 4-mesh (mesh size 4.75 mm) sieve path described in JIS Z 8801 is 80% by mass or more.

  In addition, when the particle size of the carbide is already in such a range, crushing or the like is not necessary.

<Kneading and granulation>
[Kneading (S1 in FIG. 1)]
In order to homogenize the nutrient components, it is necessary to knead the additive. The kneading conditions in the present invention are not particularly limited. For example, the kneading can be carried out at an arm of 10 rpm to 15 rpm and a rotor of 200 rpm to 400 rpm for 1 minute to 1 minute 30 seconds.

[Granulation (S2 in FIG. 1)]
By granulating the additive, its structure is changed from a single grain structure to a aggregate structure. Since dredged sand contained in the additive is clayey, it can be easily granulated, for example, by heating. For this reason, although it does not specifically limit as a heating condition for granulation in this invention, Usually, it is 200 to 270 degreeC, and is 30 second-1 minute.

  Moreover, in order to perform granulation easily, it is preferable to add a moisture adjusting agent (pulverized coal). The addition amount of the moisture adjusting agent is usually 5 to 10 parts by mass with respect to 100 parts by mass of the additive.

  When using dredged sand that has been dried to the extent that it can be granulated, granulate the dried dredged sand to obtain a granulated product, and then add plant biomass to the resulting granulated product. Powdered carbide may be added and kneaded (see broken line arrow in FIG. 1).

<Heat treatment (S3 in FIG. 1)>
In order to remove mainly germs and weed seeds, it is preferable to heat-treat the granulated product. Although it does not specifically limit as heat processing of this invention, If the point which removes miscellaneous bacteria etc. fully and cost are considered, it can carry out for 30 second-1 minute at 200 to 270 degreeC, for example.

  In addition, handling becomes very easy by granulating and drying by heat processing.

<Classification of granulated product (S4 in FIG. 1)>
In order to obtain a granular material for agricultural soil having a predetermined physical property, it is preferable to classify the granular material. In order to have excellent physical properties, the granular material for agricultural soil preferably has a sieve path of 15 mm opening described in JIS G 3553 of 80% by mass or more.

  For this reason, the classification method according to the intended use used in the present invention is not particularly limited. For example, two types of sieves, for example, an opening 15 mm (first opening) described in JIS G 3553, and JIS G 3553 are used. A method using the described opening 2 mm (second opening) can be mentioned. That is, the heat-treated granule is shaken for about 10 minutes under the conditions of a first opening of 1100 shakes / minute and a shake width of 11 mm. With the second opening, the granular material that has been a sieve pass is further recovered as a granular material for agricultural soil for raising seedlings at the same number of shakes or the like.

  Next, the present invention will be specifically described with reference to Examples, Comparative Examples, and Reference Examples. By adding plant biomass carbide to dredged soil, it is inexpensive and excellent in chemical properties, physical properties, and biological properties. As long as the essence of producing agricultural soil is not impaired, the present invention is not limited to the following examples.

<Example 1>
The driftwood (about 1m long) of Tateiwa Dam (artificial lake) is placed in a charcoal pot “GS-4000 (trade name)” (Environtech) and left at 400 ° C. for about 3 days. Carbide was obtained.

  The obtained carbide was crushed to an average particle size of 5 mm using a pulverizer “hammer mill pulverizer THM-2 (trade name)” (manufactured by Atmospheric Techno) to obtain a powdered carbide.

  Garbage (for example, vinyl, cans, etc.), stones, etc. were selected from dredged sand of the Tateiwa Dam, which had been dried for about one year, using “Power Truck 600 (trade name)” (manufactured by Power Screen).

  What added 10 mass parts of said powdered carbide | carbonized_materials with respect to 100 mass parts of the dredged clay sand is thrown into the kneading granulator "Perec (trade name)" (made by Kitagawa Iron Works), arm: 10rpm Granules were obtained by kneading and granulating at -15 rpm, rotor: 200 rpm to 400 rpm for 1 minute to 1 minute 30 seconds.

  The obtained granular material was heat-treated at 270 ° C. for 30 seconds using a heat treatment machine “Rotary kiln Gunburner MGWA555 (trade name)” (manufactured by Corona).

  The heat-treated granular material was shaken for 10 minutes under the conditions of a shaking number of 1,100 times / minute and a shaking width of 11 mm with an opening of 15 mm described in JIS G3553. Thereby, the granular material which was a sieve pass was collect | recovered as an agricultural soil granular material.

<Example 2>
Agricultural soil particulate matter was recovered under the same conditions as in Example 1 except that 30 parts by mass of powdered carbide of driftwood was added to 100 parts by mass of the dredged clay.

<Example 3>
In order to remove germs and weed seeds contained in dredged soil, heat treatment machine “Rotary Kiln Gunburner MGWA555 (trade name)” (manufactured by Corona Co., Ltd.) heat-treated at 200 ° C. to 270 ° C. for 30 seconds to 1 minute. Agricultural soil particulate matter was collected under the same conditions as in Example 2 except that the dam dredged soil was used.

<Example 4>
The rice husk was left to stand at 450 ° C. for about 3 days using a firewood combustor “Kunnen type 203 (trade name)” (manufactured by Koran Sangyo Co., Ltd.). Was in a state). And the granular material for agricultural soil was collect | recovered on the conditions similar to Example 1 except the point which was thrown into the kneading granulator without crushing the carbide | carbonized_material of the obtained rice husk.

<Example 5>
Agricultural soil granulate was recovered under the same conditions as in Example 4 except that 30 parts by mass of the above powdered carbide of rice husk was added to 100 parts by mass of the selected clay earth.

<Example 6>
Agricultural soil particulate matter was recovered under the same conditions as in Example 4 except that 50 parts by mass of the above powdered carbide of rice husks was added to 100 parts by mass of the dredged sand.

<Comparative Example 1>
Garbage (for example, vinyl, cans, etc.), stones, etc. were selected from dredged sand of the Tateiwa Dam, which had been dried for about one year, using “Power Truck 600 (trade name)” (manufactured by Power Screen).

  Agricultural soil granulate was recovered under the same conditions as in Example 1 except that no carbide was added to the selected dredged sand and granulation was not performed.

<Comparative example 2>
Using the heat treatment machine “Rotary kiln Gunburner MGWA555 (trade name)” (manufactured by Corona Co., Ltd.), using the dredged sand of the Tateiwa dam that was heat treated at 200 ° C. to 270 ° C. for 30 seconds to 1 minute, the same procedure as in Example 1 Agricultural soil granules were collected under the same conditions as in Comparative Example 1 except that the grains were formed.

<Reference Example 1>
The fertile field was recovered as it was as granular material for agricultural soil.

<Evaluation>
[Chemical evaluation]
In order to evaluate the chemical properties of the agricultural soil granules, measurements as shown in Table 1 were performed.

[Physical evaluation]
In order to evaluate the physical properties of the granular material for agricultural soil, the water permeability was measured by the variable water level method.

[Evaluation results]
Tables 2 and 3 show the results of chemical evaluation and physical evaluation.

  As shown in Table 2 and Table 3, in Comparative Examples 1 and 2, except for humus and Ca / Mg (equivalent ratio), they were not in the range of appropriate values. On the other hand, the granular materials for agricultural soil collected in Examples 1 to 6 are in the range of appropriate values in terms of electrical conductivity, substituting lime, substituting magnesium, base substitution capacity, etc. It was found to have excellent chemistry.

  Moreover, pH approached the appropriate value in the order of Examples 1, 2, and 3, and Example 4, 5, and 6 in order. Therefore, it was found that by adding the powdered carbide of plant-based biomass, the pH can be appropriately brought close to the granular material for agricultural soil (chemical properties can be improved).

  Moreover, as Table 3 showed, compared with the comparative example 1, it turned out that the granular material for agricultural soil collect | recovered in Examples 1-6 is close to an appropriate value, and is excellent in physical property. In particular, it was found that the agricultural soil granular materials recovered in Example 2 and Example 3 have water permeability in the range of appropriate values as agricultural soil, and are particularly excellent in physical properties.

  Next, agricultural soil obtained by kneading and granulating the additives obtained by adding a predetermined amount of dust compost, driftwood powdered carbide, rice husk carbide, coal ash, cow manure compost to dredged soil The more suitable granular material for agricultural soil was examined using the granular material for agriculture.

<Example 7>
Fertilizer was deposited on screens installed in intakes, sand basins, aquariums, etc. of hydroelectric power stations near Tateiwa Dam (artificial lakes) to obtain dust compost.

  Chips were crushed and shredded into a sawdust from a Tateiwa Dam (artificial lake) driftwood (about 1 m long) using a crusher “Oogeagle Portable CQ300E (trade name)” (Fuji Steel Industry Co., Ltd.) Obtained. The mixture obtained by mixing this chip with cow manure was fermented to obtain cow manure compost.

  Garbage (for example, vinyl, cans, etc.), stones, etc. were selected from dredged sand of the Tateiwa Dam, which had been dried for about one year, using “Power Truck 600 (trade name)” (manufactured by Power Screen).

  A kneading granulator “Pelec (trade name)” (Kitakawa Iron Works) is obtained by adding 20 parts by mass of the above-mentioned dust compost and 30 parts by mass of the above-mentioned cow manure compost to 50 parts by mass of the dredged clay soil. The resulting mixture was kneaded for 1 minute to 1 minute and 30 seconds at an arm of 10 rpm to 15 rpm and a rotor of 200 rpm to 400 rpm, and granulated to obtain a granular material.

  The obtained granular material was heat-treated at 270 ° C. for 30 seconds using a heat treatment machine “Rotary kiln Gunburner MGWA555 (trade name)” (manufactured by Corona).

  The heat-treated granular material was shaken for 10 minutes under the conditions of a shaking number of 1,100 times / minute and a shaking width of 11 mm with an opening of 15 mm described in JIS G3553. Thereby, the granular material which was a sieve pass was collect | recovered as an agricultural soil granular material.

<Example 8>
Example, except that 20 parts by mass of dust compost, 10 parts by mass of powdered carbide of driftwood obtained in Example 1 and 10 parts by mass of cow manure compost were added to 60 parts by mass of dredged sand Under the same conditions as in No. 7, the granular material for agricultural soil was recovered.

<Example 9>
Under the same conditions as in Example 7, except that 20 parts by mass of powdered carbide of driftwood and 20 parts by mass of cow manure compost were added to 60 parts by mass of dredged sand. It was collected.

<Example 10>
Under the same conditions as in Example 7, except that 10 parts by weight of dust compost, 10 parts by weight of powdered carbide of driftwood, and 20 parts by weight of cow manure compost were added to 60 parts by weight of the dredged soil. The granular material for agricultural soil was recovered.

<Example 11>
Agricultural soil particulate matter was recovered under the same conditions as in Example 7, except that 30 parts by mass of dust compost and 10 parts by mass of cow manure compost were added to 60 parts by mass of the dredged sand.

<Comparative Example 3>
Example, except that 10 parts by weight of dust compost, 20 parts by weight of coal ash obtained from a boiler of a thermal power plant, and 10 parts by weight of cow manure compost are added to 60 parts by weight of dredged sand Under the same conditions as in No. 7, the granular material for agricultural soil was recovered.

<Comparative example 4>
Agricultural soil particulate matter was recovered under the same conditions as in Example 7 except that 30 parts by mass of coal ash and 10 parts by mass of cow manure compost were added to 60 parts by mass of the dredged sand.

<Comparative Example 5>
Agricultural soil particulate matter was recovered under the same conditions as in Example 7 except that 20 parts by mass of coal ash and 10 parts by mass of cow manure compost were added to 70 parts by mass of the dredged sand.

<Comparative Example 6>
Agricultural soil particulate matter was recovered under the same conditions as in Example 7 except that 10 parts by mass of coal ash and 20 parts by mass of cow manure compost were added to 70 parts by mass of the dredged sand.

<Comparative Example 7>
With the same conditions as in Example 7, except that 10 parts by mass of coal ash, 10 parts by mass of powdered carbide of driftwood, and 10 parts by mass of cow manure compost were added to 70 parts by mass of dredged sand. Agricultural soil granulate was collected.

<Reference Example 2>
Agricultural soil particulate matter was recovered under the same conditions as in Example 7, except that 30 parts by mass of the carbide of rice husk obtained in Example 4 was added to 70 parts by mass of the sorted clay sand.

<Reference Example 3>
Agricultural soil particulate matter was recovered under the same conditions as in Example 7, except that 30 parts by mass of powdered carbide of driftwood obtained in Example 1 was added to 70 parts by mass of dredged sand.

<Evaluation>
[Chemical evaluation]
In order to evaluate the chemical properties of the granules for agricultural soil obtained in Examples 7 to 11, Comparative Examples 3 to 7, and Reference Examples 2 and 3, in a column (diameter 10 cm, height 20 cm), Table 1 Of the measurements shown, pH, available phosphoric acid, and electrical conductivity were measured. Moreover, the nitrogen content rate contained in the granular material for agricultural soils was measured by the N content rate measurement by a dry combustion method.

[Physical evaluation]
In order to evaluate the physical properties of the granular materials for agricultural soil obtained in Examples 7 to 11, Comparative Examples 3 to 7, and Reference Examples 2 and 3, the soil three-phase distribution by the real volume method, and the pF-moisture curve The effective water content (water retention) by (sand column method-centrifugation method) was measured. Moreover, the water transmission rate of the granular material for agricultural soil obtained in Examples 7-11, Comparative Examples 3-7, and Reference Examples 2 and 3 was measured by the following method.

  A column (diameter 10 cm, height 20 cm) is filled with the granular material for agricultural soil obtained in Examples 7 to 11, Comparative Examples 3 to 7, and Reference Examples 2 and 3 to a height of 15 cm, and from the top of the column 200 ml of water was added, and the time until water started to flow out from the bottom of the column was measured. The water transmission rate was determined by dividing the height of 15 cm by the measurement time.

[Cultivation test]
Using the agricultural soil granular materials obtained in Examples 7 to 11, Comparative Examples 3 to 7, and Reference Examples 2 and 3, a cultivation test (seedling growth test) with Komatsuna was performed by the following method.

  A column (diameter 10 cm, height 20 cm) is filled with the agricultural soil granules obtained in Examples 7-11, Comparative Examples 3-7, and Reference Examples 2 and 3, and Komatsuna is used as the agricultural soil granules. After seeding 10 grains per column, it was cultivated for 30 days.

  The plant height (cm) of Komatsuna on the 10th, 20th, and 30th was measured, and the harvest amount of Komatsuna (the amount of dry matter on the ground) collected on the 30th day and the phosphorus content of Komatsuna were determined as follows. .

  The above-ground dry weight of Komatsuna was measured by cutting the grown Komatsuna from the column, measuring the fresh weight, drying at 80 ° C. for 48 hours, and measuring the dry weight. In addition, after the cut plant body was decomposed with sulfur nitrate, the phosphorus content was measured by the molybdenum sulfate method.

[Evaluation results]
Table 4 shows the results of chemical evaluation and physical evaluation. Table 5 shows the results of the cultivation test.

  As shown in Table 4, the pH was outside the appropriate value range in Comparative Examples 4, 5, and 7, but the Examples, Reference Examples, and other Comparative Examples were within the appropriate value range. The effective phosphoric acid was low in Comparative Examples 3 to 7 and Reference Examples 2 and 3, whereas it was high in all Examples 7 to 11. The electrical conductivity was within an appropriate value range except for Example 7. The nitrogen content was low in Comparative Examples 4 and 5 and Reference Examples 2 and 3, whereas it was high in all Examples 7-11. That is, it was found that Examples 7 to 11 had better chemical properties than Comparative Examples 3 to 7 and Reference Examples 2 and 3.

  Moreover, as shown in Table 4, the water permeation rate was a constant value (10 mm / s) or more in all cases. The effective water content was the smallest in Example 7 and the largest in Comparative Example 3. As for the three-phase distribution, in all the agricultural soil granular materials, the gas phase rate was as high as about 50%, and except for Reference Examples 2 and 3, the solid phase rate was as low as 40% or less. That is, it was found that the physical properties of Examples 7 to 11 were comparable to those of Comparative Examples 3 to 7 and Reference Examples 2 and 3.

  Moreover, as shown in Table 5, the plant height of Komatsuna was low in Comparative Examples 3 to 7 and Reference Examples 2 and 3, whereas it was high in Examples 7 to 11. The amount of the above-ground dry matter of Komatsuna was light in Comparative Examples 3 to 7 and Reference Examples 2 and 3, whereas it was heavy in all of Examples 7 to 11. The phosphorus content of Komatsuna was generally high except in Reference Examples 2 and 3, but the phosphorus content was particularly high in Examples 7 to 11.

  As a result of the above, the reason why Komatsuna grew well in Examples 7 to 11 was that physical properties were improved by adding powdered carbides and dust compost of driftwood, and dust compost and cow manure compost were added. This is thought to be due to the improvement in chemistry.

  In other words, on the clay-type dredged sand from which natural or artificial lake bottom soil has been drowned, powdered charcoal from driftwood obtained from the lake, organic dust obtained from the intake of the hydroelectric power plant near the lake, etc. The fertilizer compost obtained by fermentation, the additive to which the manure compost obtained by fermenting the mixture obtained by mixing the chip obtained by fragmenting the driftwood obtained from the lake and the manure of the cow was added By uniformly kneading and granulating, it is possible to provide agricultural soil that is superior in chemical properties, physical properties, and biological properties.

It is a figure showing the flow of embodiment (manufacturing process) of this invention.

Claims (15)

  An additive in which a predetermined amount of plant-based biomass powdered carbide obtained from the surrounding area and / or the downstream area of the lake is added to clay-type dredged sand in which the bottom sediment of natural or artificial lake is dredged. Agricultural soil granules that are uniformly kneaded and granulated.   The plant-derived biomass obtained from the surrounding area and / or downstream area of the lake is added to the granulated material obtained by granulating clayey dried dredged earth and sand from the natural or artificial lake. A granular material for agricultural soil, in which an additive to which a predetermined amount of powdered carbide is added is uniformly kneaded.   The granular material for agricultural soil according to claim 1 or 2, wherein the plant biomass is woody biomass and / or agricultural waste. The woody biomass is a driftwood obtained from the lake,
The granular material for agricultural soil according to claim 3, wherein the agricultural waste is rice husk obtained from a downstream area of the lake.   The granular material for agricultural soil according to any one of claims 1 to 4, wherein the additive is added with a predetermined amount of compost or organic fertilizer containing nitrogen and phosphorus before the granulation. In 60 parts by mass of clay-like dredged soil from which natural or artificial lake bottom soil has been dredged,
(A) 5-25 parts by mass of powdered carbide of driftwood obtained from the lake,
(B) 5-25 parts by weight of dust compost obtained by fermenting organic dust obtained from a hydropower station intake near the lake, etc.
(C) 5-25 parts by mass of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by fragmenting driftwood obtained from the lake and cow manure,
(However, the total of the additives (A), (B), and (C) is 40 parts by mass)
Agricultural soil granular material obtained by uniformly kneading and granulating an additive to which is added. In 60 parts by mass of clay-like dredged soil from which natural or artificial lake bottom soil has been dredged,
(A) 5-25 parts by mass of powdered carbide of driftwood obtained from the lake,
(B) 15-35 parts by weight of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by fragmenting driftwood obtained from the lake and cow manure;
(However, the sum of the additives (A) and (B) is 40 parts by mass)
Agricultural soil granular material obtained by uniformly kneading and granulating an additive to which is added. In 60 parts by mass of clay-like dredged soil from which natural or artificial lake bottom soil has been dredged,
(A) 5 to 35 parts by weight of dust compost obtained by fermenting organic dust obtained from a hydroelectric power plant intake near the lake and the like,
(B) 5 to 35 parts by weight of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by fragmenting driftwood obtained from the lake and cow manure,
(However, the sum of the additives (A) and (B) is 40 parts by mass)
Agricultural soil granular material obtained by uniformly kneading and granulating an additive to which is added. In 60 parts by mass of the granulated material in which clay-dried dredged dredged soil sand from which natural or artificial lake sediment has been dredged is granulated,
(A) 5-25 parts by mass of powdered carbide of driftwood obtained from the lake,
(B) 5-25 parts by weight of dust compost obtained by fermenting organic dust obtained from a hydropower station intake near the lake, etc.
(C) 5-25 parts by mass of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by fragmenting driftwood obtained from the lake and cow manure,
(However, the total of the additives (A), (B), and (C) is 40 parts by mass)
Agricultural soil granular material obtained by uniformly kneading an additive to which is added. In 60 parts by mass of the granulated material in which clay-dried dredged dredged soil sand from which natural or artificial lake sediment has been dredged is granulated,
(A) 5-25 parts by mass of powdered carbide of driftwood obtained from the lake,
(B) 15-35 parts by weight of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by fragmenting driftwood obtained from the lake and cow manure;
(However, the sum of the additives (A) and (B) is 40 parts by mass)
Agricultural soil granular material obtained by uniformly kneading an additive to which is added. In 60 parts by mass of the granulated material in which clay-dried dredged dredged soil sand from which natural or artificial lake sediment has been dredged is granulated,
(A) 5 to 35 parts by weight of dust compost obtained by fermenting organic dust obtained from a hydroelectric power plant intake near the lake and the like,
(B) 5 to 35 parts by weight of cow manure compost obtained by fermenting a mixture obtained by mixing chips obtained by fragmenting driftwood obtained from the lake and cow manure,
(However, the sum of the additives (A) and (B) is 40 parts by mass)
Agricultural soil granular material obtained by uniformly kneading an additive to which is added.   The granular material for agricultural soil according to any one of claims 1 to 11, wherein a sieve path having an opening of 15 mm according to JIS G 3553 is 80 mass% or more.   The continuous crop disorder reducing material which has the granular material for agricultural soil in any one of Claim 1 to 12 as a main component.   Agricultural soil improvement material mainly composed of powdered carbide of driftwood and / or rice husk.   A granulated product obtained by granulating clayey dried dredged sand that has been dredged with natural or artificial lake sediment, and plant biomass obtained from the surrounding area and / or downstream area of the lake. An agricultural soil improvement method using powdered carbide as agricultural soil in the downstream area of the lake.

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