JPH06271379A - Granulated formed product - Google Patents

Abstract

PURPOSE:To strengthen the slow-releasing property of a nitrogenous fertilizer by mixing a biodegradable slow-release nitrogenous fertilizer, zeolite and acid, granulating and forming them, and specifying the pH of a resulting product to a prescribed value or below. CONSTITUTION:One pts.wt. a biodegradable slow-release nitrogenous fertilizer having relatively low solubility to water (e.g. oxamid dioxalic acid diazide, ureaform, crotolyden diurea, glycoluril, guanylurea), 0.1-9 pts.wt. zeolite (e.g. the powder of the natural zeolite consisting essentially of clinoptilolite or mordenite), 0.1-5 pts.wt. acid (e.g. an inorg. acid or an org. acid, particularly, citric acid and itaconic acid) and a little water is mixed and granulated. At this time, acidic zeolite and salt are generated by cation exchange reaction of acid and the zeolite, and pH is specified to <=4, preferably 1-4. The formed product forming the material is suitable to be used in the production of a paddy rice, a field crop, vegetable, etc., as the nitrogenous fertilizer providing with the slow-releasing property more than conventional biodegradable slow-release nitrogenous fertilizer.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a slow-release nitrogen fertilizer for growing plants.

[0002]

2. Description of the Related Art The application of fertilizer components is indispensable for the cultivation of agricultural products, of which the nitrogen component is the most important. Conventionally,
Ammonium sulfate, ammonium chloride, as nitrogen fertilizer,
Although fast-acting chemical fertilizers such as urea have been widely used, recently, slow-acting nitrogen fertilizers have been widely used from the viewpoint of reducing the labor of fertilizer application work or improving the quality of agricultural products.

The slow-acting nitrogen fertilizer chemically changes the form of nitrogen, and gradually decomposes the fertilizer in soil by microbial decomposition or hydrolysis. It is roughly classified into two types, one that regulates the elution of nitrogen components by covering with a covering material.

The latter exhibits a slow-acting effect by a physical action, so that the elution period can be freely controlled by changing the type and thickness of the coating material. On the other hand, in the case of a hydrolytic slow-release nitrogen fertilizer that exhibits a slow release due to a chemical action, the slow release is enhanced by increasing the particle size.

On the other hand, in the case of microbial-degrading slow-release nitrogen fertilizer, it is possible to enhance the slow-release effect to some extent by increasing the particle size as in the case of hydrolyzing slow-release nitrogen fertilizer. The fertilizing effect appears relatively quickly in the matured fields where the microbial activity of is increasing. That is, of the three types of slow-release nitrogen fertilizers, the biodegradable slow-release nitrogen fertilizer is the most difficult to control slow-release.

However, since the fertilizer itself serves as a substrate for microorganisms in the microbial decomposition type slow-release nitrogen fertilizer, its application increases the microbial activity of the soil.

[0007] Generally, the growth of plants is so-called sigmoid curve, which is slow from the beginning of germination to the beginning and is vigorous after the middle stage.

[0008] Since mineralization and elution of coated and hydrolyzable slow-release nitrogen fertilizers are governed by physical and chemical conditions in soil, they proceed at a substantially constant rate after application,
Since the biodegradable slow-release nitrogen fertilizer undergoes mineralization by the action of microorganisms, the release of nitrogen components best matches the growth pattern of plants.

From the above two points, the microorganism-degrading slow-release nitrogen fertilizer has the characteristics not found in the coated or hydrolyzable slow-release nitrogen fertilizer. Therefore, it is desired to develop a technique for enhancing the slow-release effect of microbial-degradable slow-release nitrogen fertilizer.

[0010]

DISCLOSURE OF THE INVENTION The present invention is directed to the slow-release of microbial-degrading slow-release nitrogen fertilizers by suppressing the decomposition of microbial-degrading slow-release nitrogen fertilizers and nitrification of ammonium ions produced by the degradation. Is to further strengthen.

[0011]

In order to solve the above problems, the present invention comprises the following. 1. A granulated molded product characterized by mixing, granulating and molding a microbial decomposition type slow-release nitrogen fertilizer, zeolite and an acid, and adjusting the pH of the resulting molded product to 4 or less.

2. The pH of the product mixture is obtained by mixing, granulating and molding 1 part to 50 parts of zeolite and 0.1 part to 5 parts of organic acid with a small amount of water to 1 part of biodegradable slow-release nitrogen fertilizer. Is 4 or less, preferably 1 to 4
A granulated molded product characterized by the following.

<Production Method of Product of the Present Invention> The granulated molded product of the present invention can be obtained, for example, as follows.
That is, a microbial-degrading slow-release nitrogen fertilizer, zeolite and an acid are mixed, granulated and molded to adjust the pH of the resulting molded product to 4 or less, or preferably a sparingly microbial-degrading slow-release such as oxamide. 0.1 part to 9 parts of natural zeolite is added to 1 part of nitrogen fertilizer and mixed, and an acid such as citric acid or itaconic acid is added and mixed at a ratio of 0.1 part to 5 parts, and the pH of the resulting mixture is adjusted. Is 4 or less, preferably 1 to 4.

After adding 0.01 part to 0.2 part to 1 part of a mixture consisting of a small amount of water, for example, a microbial decomposition type slow-release nitrogen fertilizer, zeolite and acid, and mixing well, pelletizer and the like. Using the above granulating apparatus, it is preferable to granulate and mold to an average diameter of about 1 mm to 20 mm. This is dried to obtain a granulated product of the present invention. When granulation molding is carried out without using water, application to soil absorbs water in the soil and the reaction between zeolite and acid proceeds.

In the present invention, when the pH of the granulated product exceeds 4, the decomposition of slow-release nitrogen fertilizer by microorganisms cannot be suppressed.

<Microorganism-degrading slow-release nitrogen fertilizer> Here, the term "microorganism-degrading slow-release nitrogen fertilizer" means that the form of nitrogen is chemically changed and decomposed by the action of microorganisms in the soil to produce ammonium ions or urea. It is a slow-release nitrogen fertilizer that produces oxamide, ureaform, CDU (crotonylidene 2 urea), glycoluril, guanylurea, and the like. In order to obtain the product of the present invention, those having relatively low solubility in water are preferable.

<Zeolaroto> Next, in the present invention, Zeoraoto is an aluminosilicate mineral having a three-dimensional knit structure, which is obtained by natural or synthetic synthesis and is called "Zeoite" in Japanese, and its general formula is Me _{2 / n.} O ・ Al ₂ O ₃・ xSiO ₂・ yH ₂ O
(Me: alkali or alkaline earth metal, n: charge of Me, x, y: coefficient). In order to obtain the product of the present invention, it is preferable to use, as the zeolite, for example, a powdered product of natural zeolite containing clinoptilolite or mordenite as a main component.

<Acid> The acid used in the present invention refers to an inorganic acid or an organic acid, the inorganic acid refers to hydrochloric acid, sulfuric acid, nitric acid, etc., and the organic acid has a carboxyl group and exhibits the properties of acid. Says carboxylic acid. In order to obtain the product of the present invention, in addition to citric acid and itaconic acid, organic acids exhibiting water solubility such as formic acid, acetic acid, malic acid and lactic acid are preferable because the pH can be easily adjusted.

In the present invention, preferably 0.1 part to 9 parts of zeolaoto is mixed with 1 part of the microorganism-degrading slow-release nitrogen fertilizer. When the mixing ratio of Zeolaoto is less than 0.1 part to 1 part of biodegradable slow-release nitrogen fertilizer, ammonium ions generated by decomposition of fertilizer cannot be completely captured, and conversely exceeds 9 parts. And the nitrogen content in the mixed granulated product decreases, and a large amount of organic acid needs to be added, which impairs its practicality.

In the present invention, the pH of the resulting granulated molded product is 4 or less, preferably 1 to 4. When the pH of the formed granulated product is 1 or less, the structure of the zeolite may gradually change depending on the case.

In the present invention, the pH is measured in Showa 62.
Published December 20, 2014, written by the Ministry of Agriculture, Forestry and Fisheries, Agricultural Environmental Technology Research Institute, published by the Japan Fertility Examination Association, "Fertilizer Analysis Method" (1
(1987 edition) page 7, line 17 to page 8, line 18

Here, 0.1 part to 5 parts of the acid is preferably mixed with 1 part of the microorganism-degrading slow-release nitrogen fertilizer.
If the acid content is 0.1 part or less, it is often difficult to maintain the desired pH range, and if it exceeds 5 parts, it is difficult to form the nitrogen component of the present invention so as to form a sigmoid curve. There are many.

[0023]

The present invention has the following functions due to the above-mentioned constitution. The biodegradable slow-release nitrogen fertilizer, which is a mixed granulation product of zeolite and acid, of the present invention enhances the slow-release effect of the biodegradable slow-release nitrogen fertilizer by the following mechanism of action in soil. .

In the course of granulation of the product of the present invention, the pH of the product of the present invention is 4 or less, preferably 1 to 4 due to the formation of a salt with an acidic zeolite by a cation exchange reaction between an acid and zeolite.

The salt formed at this time is a calcium salt, a magnesium salt, a potassium salt, a sodium salt or the like of an inorganic acid or an organic acid. In addition, if an acid is added and mixed in an amount not less than the reaction amount with zeolite and remains in the product of the present invention as a free inorganic acid or an organic acid, when the pH of the mixed granulated product is in the range of 1 or more and 4 or less, There is no problem in growing plants.

When the product of the present invention is applied as a fertilizer to soil, it will be decomposed by microorganisms in the soil, but since the pH is 4 or less, a slow-release nitrogen fertilizer alone is granulated and formed. As a result, decomposition is suppressed.

However, since the surface of the product of the present invention is neutralized by contact with soil to raise the pH, the granulated molded product of the present invention is gradually decomposed by the action of microorganisms to produce ammonium ions.

The ammonium ions are specifically captured by the acidic zeolite in the mixture, and the conversion to nitrate ions is delayed by suppressing the nitrification.

Due to the respective roles of the acid and zeolite added to the microbial-degradable slow-release nitrogen fertilizer, the product of the present invention has significantly slower-release effect than that obtained by granulating and molding the slow-release nitrogen fertilizer alone. Become.

For example, oxamide, which is a microbial-degradable slow-release nitrogen fertilizer, is hardly soluble in water and does not change under acidic conditions, so it is optimal as a raw material for producing the product of the present invention. In addition, zeolite does not change its structure or ammonium ion-specific trapping property under acidic conditions of pH 1 or more.

Since the salt formed by reacting with the acid contained in the product of the present invention is water-soluble, it gradually elutes and supplies components essential for plant growth such as calcium, magnesium and potassium into the soil. .

Further, the salt, particularly the organic acid salt, contained in the product of the present invention serves as a substrate for soil microorganisms, which is useful for enhancing the activity of soil microorganisms.

Further, since the zeolite contained in the product of the present invention remains in the soil even after the slow-release nitrogen fertilizer is decomposed, it plays a role of enhancing the fertilizing ability of the soil.

The role of the zeolite in the present invention is to keep the pH of the product of the present invention low in soil. Without adding zeolite, mixing only slow-release nitrogen fertilizer and acid, granulated and molded, the added acid is simply washed off by water, so expected slow-release enhancement of the present invention. You cannot do it.

As an alternative to zeolite, for example,
When bentonite and acid clay are used, they have a drawback that their structure is changed under acidic conditions or they exhibit swelling property, so that the granulated product easily collapses in soil and it is difficult to sufficiently maintain its slow release effect.

[0036]

Example 1 Powdery oxamide (oxalic acid diamide) 1
Part and 1 part of natural zeolite mainly composed of clinoptilolite from Aizu, Fukushima Prefecture, was mixed with 0.3 part of citric acid. After 0.2 part of water was added to this and mixed well, it was granulated into a diameter of 2 mm and a length of 5 mm using a pelletizer. This was dried to obtain a slow-acting nitrogen fertilizer granulated product of the present invention having a pH of 2.6.

In addition to the product of the present invention, urea, oxamide granules and coated urea (40 day type) were used as a comparison for alluvial upland soil 1
0.5 g of nitrogen was applied to each of the kg to make the water content in a field, and the mixture was kept warm at a temperature of 30 ° C. for 4 weeks. The amount of ammonium ion and nitrate ion in soil was quantified every week.

As a result, as shown in Table 1, the amount of ammonium ion and nitrate ion produced in the group to which the present invention was applied was smaller than that in the other groups.

[Table 1]

[Table 2]

As a result, the electric conductivity of the soil decreased as shown in Table 2. Particularly, the effect is remarkable for 1 to 2 weeks after application, and it is possible to provide a favorable environment for seed germination and initial growth. In particular, the amount of ammonium ion and nitrate ion produced was smaller than that when oxamide, which is a raw material of the product of the present invention, was used alone, and the electrical conductivity was lowered, and the addition of zeolite and citric acid enhanced the slow-release effect of oxamide. It is clear that

As is clear from Tables 1 and 2, the decomposition of the product of the present invention is accelerated from about 3 weeks after application, and after 4 weeks, nitrate ions can be supplied in the same manner as oxamide and coated urea. As a result, the growth after the middle stage is promoted.

As described above, in the product section of the present invention, 1 to 2
As a result of suppressing the decomposition for a week, the elution rate of nitrogen fertilizer after 5 weeks was lower than that of oxamide and coated urea (40-day type). That is, it is clear from this example that the addition of zeolite and citric acid enhances the slow-release effect of oxamide.

When the product of the present invention is applied to soil as fertilizer,
Nitrogen components are efficiently supplied to the growing plant,
The runoff of nitrate ions to groundwater is suppressed.

[0043]

Example 2 A product of the present invention was obtained in the same manner as in Example 1 except that 1 part of powdered oxamide and 1 part of natural zeolite mainly composed of clinoptilolite from Aizu, Fukushima Prefecture were used as 1 part of citric acid. In addition to the product of the present invention, urea, granular oxamide, and coated urea (40-day type) were applied to 2 kg of black soil as nitrogen for comparison, and 0.5 g of nitrogen and 6 g of lime superphosphate and 1 g of potassium chloride were applied to all plots. And filled in a 1 / 5000a (R) Wagner pot.

Komatsuna was cultivated in a glass greenhouse for 30 days, and the yield and the nitric acid and reducing sugar contents were measured. As a result, the germination rate of Komatsuna was almost 100% in all plots. The yields were almost the same as shown in Table 3, but the smaller the amount, the higher the safer the nitric acid content was in the present invention group.

On the contrary, the reducing sugar content related to the taste and the shelf life was the highest in the present invention group, and it was revealed that the use of the present invention product improves the quality of vegetables.

[Table 3]

It is generally known that the quality of vegetables increases as the release rate of nitrogen components decreases. That is, this result supports that the slow-release effect of the product of the present invention was further enhanced as compared with the case of oxamide alone.

[0047]

EFFECTS OF THE INVENTION As is clear from the above, a granulated product having a pH of 4 or less is obtained by mixing the zeolite and acid with the microorganism-degrading slow-release nitrogen fertilizer of the present invention, granulating and molding the mixture. The molded product is suitable as a nitrogen fertilizer having a slower release effect than conventional microbial-degrading slow-release nitrogen fertilizers and is suitable for use in the production of rice, field crops, vegetables and the like.

By enhancing the slow release of nitrogen fertilizer,
Since the nitrogen component corresponding to the growth of vegetables can be supplied, the quality of the product is improved. In addition, the fertilization efficiency of nitrogen components is improved and the runoff of nitrate ions into groundwater is suppressed.

Zeolite, which is a raw material of the product of the present invention, is a natural mineral that is mass-produced in Japan and is an unused resource that should be effectively utilized in the future. That is, the present invention contributes to quality improvement of crops, environmental protection, and effective use of domestically unused resources.

Claims (2)

[Claims] 1. A granulated molded product characterized in that a microbial degradable slow-release nitrogen fertilizer, zeolite and an acid are mixed, granulated and molded, and the pH of the molded product is adjusted to 4 or less. 2. Mixing and granulating 0.1 part to 9 parts of zeolite and 0.1 part to 5 parts of organic acid with a small amount of water to 1 part of microbial decomposition type slow-release nitrogen fertilizer, and granulating, A granulated molded product characterized by being molded and having a pH of the resulting molded product of 1 to 4.