JPH0611678B2 - Organic fertilizer that does not impair the growth of crops - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a powder that does not impair the germination and survival of a crop even when it is sown or planted immediately after being applied to soil, and when mixed with other inorganic fertilizers, it is powdered. The present invention relates to an organic fertilizer that does not easily turn into granules and maintains its granular form even in flooded water.

Conventional technology and its problems Fertilization technology is an extremely important technology in crop production, and many studies are still in progress. At that time, the relationship between the type of fertilizer and the fertilization technique is deep, and fertilization methods and fertilization amounts that take advantage of their respective characteristics are being studied. In particular, since organic fertilizers have been used for a long time, their research is not small.

In recent years, mainly in the horticultural field, due to the characteristics of nutrient supply of organic fertilizers, that is, slow-release properties, increase of microbial activity, improvement of soil physical properties, and improvement of crop quality as a total effect of these, organic substances are re-established. The amount of fertilizer used is increasing.

On the other hand, wastes from the food industry, fermentation industry, etc. and fungal fertilizers obtained by drying excess sludge from water treatment are also used as organic fertilizers. However, immediately after the application of the organic fertilizer or the fresh organic matter, growth disorders such as germination inhibition and poor survival often appear.

The reason for this is that the easily decomposable part of the applied organic fertilizer and fresh organic matter is rapidly decomposed, resulting in an increase in carbon dioxide and lack of oxygen, growth of harmful microorganisms, or the presence of germination inhibitors. Has been pointed out. However, there is no means for avoiding these growth disorders and effectively utilizing all the characteristics of organic fertilizers. Currently, the main fertilizer is mainly used, and the fertilizer is applied 1 to 2 weeks before the planting, and the rapid change is delivered. After that, the actual condition is to sow or plant.

However, according to such an application method, the mineralization of the organic fertilizer has progressed considerably before the planting, and it is not possible to sufficiently utilize the slow-release property which is one of the original characteristics of the organic fertilizer. . For example, when rapeseed meal is applied to soil and incubated for 2 weeks, about 50% of organic nitrogen becomes mineralized [Special Report No. 1 of the Agricultural Research Center for Agriculture and Agricultural Research on the effect of applying organic fertilizers (198
3)]. Therefore, if a large amount of organic fertilizer is applied,
Another factor of the safety of organic fertilizers cannot be fully utilized, because the salt concentration of soil increases during planting, which may cause growth failure.

On the other hand, in recent years, in order to reduce the production cost of agricultural products, the production technology has been reviewed from various directions. From the same viewpoint, fertilizers, in addition to conventional chemical fertilizers, have started to spread single fertilizer compound fertilizers (so-called BB fertilizers) mainly in paddy rice and are being spread to field crops. However, organic fertilizers have been widely used in field crops, especially in the field of horticulture, and BB fertilizers, which are inorganic fertilizers, cannot sufficiently meet the demands of consumers.

Therefore, in order to use the organic fertilizer as the BB fertilizer, a part of granular or pellet organic fertilizer is used. However, these fertilizers are often pulverized by mixing with inorganic fertilizers, and even after application, they absorb water and easily disintegrate, so that satisfactory organic granular fertilizers have not yet been obtained. .

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In view of the above circumstances, the present inventors have completed the invention of an organic fertilizer previously treated with an aldehyde, and provided an organic fertilizer that reduces growth disorders.

(JP-A 1-294587). However, this organic fertilizer also has problems such as the need to take measures against the deterioration of the working environment due to the use of aldehyde.

The present invention is to provide an organic fertilizer that further reduces growth disorders, and to provide an organic fertilizer having a small powdering rate when formed into a granular product and having good shape retention in water. To do.

The present invention will be described in detail below.

Means for Solving the Problems A feature of the present invention is that formaldehyde and urea are replaced with urea /
This is because the formaldehyde-rich slurry (hereinafter abbreviated as formaldehyde-urea slurry) obtained by mixing and condensing HCHO in a molar ratio of 1.32 or less was added to and mixed with the organic fertilizer raw material.

The organic fertilizer raw material referred to here is a fertilizer derived from various plants and animals such as vegetable oil dregs (eg, rapeseed dregs) and fish dregs; a fertilizer derived from a plant or animal waste produced from a food factory; a fermentative production. Fertilizers derived from microbial cells obtained during material processing, sewage treatment, etc .; a wide range of such substances as a mixture of these fertilizers and other organic fertilizers stipulated in official standards for ordinary fertilizers based on the regulations of the Fertilizer Control Law are included.

The present invention is an organic fertilizer in which a formaldehyde-urea slurry is added to and mixed with the above-mentioned organic fertilizer raw material and, if necessary, granulated.

The amount of the formaldehyde-urea slurry added to the organic fertilizer is not particularly limited, but in order to reduce production damage to crops, formaldehyde is added as 0.1
It is preferable to add the formaldehyde-urea slurry in an amount of about 4% by weight. It should be noted that, in order to ensure the effect of reducing growth damage by formaldehyde, the addition of urea is not essential, but without reducing this effect,
In order to improve the working environment and enhance the hardness and shape retention in water when the granular fertilizer described later is used, it is effective to add 1.32 mol or less of urea to 1 mol of formaldehyde. In this way, the formaldehyde-urea slurry was a mixture of formaldehyde and urea so that the urea / HCHO molar ratio was 1.32 or less, and both were undergoing a condensation reaction, thus reducing the free formaldehyde. However, it has been clarified that the growth damage reduction effect on crops is not changed at all. On the other hand, as described above, since the free formaldehyde is reduced, the working environment is improved in the production of the organic fertilizer according to the present invention.

The expression of the reduction effect of the organic fertilizer generation disorder by the blending of formaldehyde-urea slurry was described in the previous invention (JP-A-1-29).
4587), it is considered to be the effect of formaldehyde, but even in the case of a slurry in which free formaldehyde is reduced by the condensation reaction of formaldehyde and urea, the effect is exhibited at the same level of addition. Therefore, it is presumed that the formaldehyde-urea condensate also has a microbial activity alleviation or a direct action on the germination inhibitor.

On the other hand, in order to improve the hardness and shape retention in water of the granulated organic fertilizer, formaldehyde-urea slurry
Addition by weight or more is preferable.

The improvement in hardness and shape retention in water of the granular organic fertilizer by adding the formaldehyde-urea slurry is due to the adhesive effect of the condensate.

In this case, formaldehyde-urea slurry urea HCHO
When the ratio exceeds 1.32 and the amount of urea increases, the adhesive strength, which is considered to be due to a decrease in the degree of condensation, becomes weak, and the hardness of the granular organic fertilizer and the degree of improvement in the shape retention in water decrease.

As described above, with respect to various organic fertilizer raw materials, by adding formaldehyde-urea slurry, kneading and further granulating, while reducing the growth disorders due to the initial rapid decomposition of the organic fertilizer, It is possible to provide a very useful organic fertilizer that has high hardness and does not easily disintegrate even in water.

The present invention and its effects will be specifically described below with reference to examples.

Example 1 Formalin (37%) 570 g (HCHO 7 mol) was adjusted to pH 7 with 10% sodium hydroxide, urea 420 g (7 mol) was added, and the mixture was reacted at a temperature of 60 to 70 ° C. for 2 hours with stirring. A syrup formaldehyde-urea slurry was formed.

25 parts by weight of rapeseed meal, 15 parts by weight of leather powder, 50 parts by weight of bone powder, and 10 parts by weight of wood peat were mixed with an organic fertilizer to formaldehyde-urea slurry (urea / HC
After adding 1% by weight, 5% by weight, and 10% by weight of HO molar ratio of 1.0), respectively, moisture-controlled granulation was performed to obtain granular products having a particle diameter of 2 mm to 4 mm. Further, as a control fertilizer, a granulated product without adding the above slurry was obtained.

The hardness of the obtained granulated product was measured with a Kiya type hardness meter. The shape retention property in water was evaluated by placing fertilizer grains in a vat filled with water and observing the state of grain disintegration.

The results are shown in Table 1.

Example 2 The BB fertilizer was prepared by mixing 30 parts by weight of the fertilizer of the present invention or the control fertilizer produced in Example 1, 37 parts by weight of ammonium sulfate, 13 parts by weight of phosphorus ammonium, and 20 parts by weight of potassium sulfate, and preparing a BB fertilizer in a plastic bag. 50 after packing and sealing
The temperature was changed to 12 hours at 5 ° C. for 12 hours, and the temperature was changed to 12 hours at 5 ° C. for 12 days.

The results are shown in Table 2.

Example 3 A plant damage test was conducted using the fertilizer of the present invention and the control fertilizer produced in Example 1. The test method was to fill the Neubauer pot with 400 g of soil as dry soil, apply 100 mg of each fertilizer as nitrogen as the test fertilizer, and apply the maximum water capacity of 50
After adjusting the water content to%, 20 seeds of Komatsuna were sown per pot. The germination rate was examined 5 days after seeding.

The results are shown in Table 3.

Example 4 5% by weight of formaldehyde-urea slurry (urea / HCHO molar ratio 0.8) was added to rapeseed meal or rice bran and granulated and dried to obtain a product having a particle size of 2 to 4 mm. As a control fertilizer, only rapeseed meal or rice bran was granulated and dried to obtain a fertilizer having a particle size of 2 to 4 mm.

A plant damage test was conducted in the same manner as in Example 2 for these granular products or powders obtained by pulverizing these granular products to 1 mm or less. However, the germination rate was investigated on the 7th day after sowing.

The results are shown in Table 4.

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display area C05F 15/00 7057-4H

Claims (3)

[Claims] 1. An organic fertilizer obtained by adding and mixing a slurry obtained by mixing formaldehyde and urea with stirring such that the urea / HCHO molar ratio is 1.32 or less. 2. The organic fertilizer according to claim 1, which is in a granular form. 3. The organic fertilizer raw material is one kind or a mixture of two or more kinds selected from the group consisting of vegetable oil dregs, fish dregs, rice bran, food processing wastes, fungal fertilizers and the like. The organic fertilizer described in (1).