JP3127308B2 - Granulation method of organic fertilizer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for granulating an organic fertilizer using organic raw material powder.

[0002]

2. Description of the Related Art Granulation of organic fertilizers is difficult when using a granulator such as a paddle type, a bread type, and a drum type, which is generally used for granulating inorganic fertilizers. Even if a granulation aid is used, it has not been put to practical use because the granulation yield is poor. For this reason, extrusion granulators, compression granulators,
Some granules are produced, but when they are used for mechanical fertilization, etc., they are not spherical because the granules are not spherical, and these granulators are compared with other granulators. Therefore, the equipment cost and the operating cost per unit production are high, and it is not economical for mass production.

For example, as a method of granulating chicken dung, raw material powder is supplied from above into a cylindrical housing rotating at a high speed inside, and is suspended in this housing and rotated in upper and lower surfaces and in a circumferential direction. In addition, there is a method in which the powder is caused to rotate and sprinkle with a large number of water droplets in the housing to agglomerate the powder (JP-A-2-88483). However, according to this method, for example, granulation of organic powder such as rapeseed meal using a vertical stirring granulator results in a poor granulation yield and a low hardness of the formed granules. In the next drying step using a rotary dryer or the like, there is a problem that the powder is crushed and powdered, the yield is further deteriorated, and it is not economical.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for efficiently and at a low cost of granulating an organic fertilizer having high hardness.

The inventors of the present invention have conducted intensive studies in view of the above problems. As a result, when granulating organic fertilizer, these raw material powders were first formed into coherent particle nuclei in the first step. In the second step, if a method of growing and sizing the particles using another granulator is performed, the obtained granulated product (wet) is crushed in the next drying step using a rotary drier or the like. ,
The inventors of the present invention have found that organic fertilizers can be efficiently and economically granulated without causing problems such as powdering.

That is, according to the present invention, when granulating an organic fertilizer, powder of an organic raw material is supplied to a cylindrical housing in which a rotating blade is rotating at a high speed, and the powder is suspended in the housing in a vertical direction. And a first step of forming a particle nucleus by rotating and rotating in the circumferential direction, and
The particle nucleus is continuously supplied to another granulator, and a granulated product having a particle size of 1 to 4 mm is obtained by a second step of granulating, growing, and sizing, and a drying step. The present invention relates to a method for granulating an organic fertilizer, characterized in that:

The mechanism of granulation using these tumbling granulators is divided into a nucleation stage, a growth stage, and a completion stage. In this nucleation stage, the powder raw material charged into the granulator is predisposed or the liquid given in the granulator associates with the individual particles and becomes discontinuous around the contact point between the powder constituent particles. Initially, loose aggregates are formed by forming a concave lens-like liquid bridge, but when this is rolled, the aggregates are gradually tightened and the voids between the particles are reduced, but they are added. Since the liquid is still locally scattered, it easily adheres and bonds to the small pieces when they come into contact with the small pieces to form larger aggregates. This is the nucleation stage.

[0008] The nucleus thus formed is such that, at the growth stage, if an appropriate amount of liquid in the interparticle space is distributed almost uniformly in the interstices, the granulated material has plasticity and an excessive liquid film is formed on the surface. As long as it collides with other smaller granules, it deforms itself and embraces the opponent, or if the opponent is weak, destroys it and kneads the debris into its own surface,
Become one and further roll to form a sphere. When colliding with granulated materials having the same size and strength, material exchange may be performed by friction on the mutual surfaces. By repeating such phenomena, the granulated material gradually increases in rolling consolidation and becomes high in strength. This is the growth stage.

As the next stage, in the completion stage, when the supply of the liquid is stopped, the excess liquid of the granules is used up for growth, the liquid in the intergranular space is reduced, and the liquid is transferred from the surface of the granules to the inside. As a result, the so-called “surface-dried granulated material” having a stronger internal binding force than a granulated material having a large amount of liquid is obtained by increasing the capillary force of the retracted surface. Furthermore, when the liquid content is reduced by tumbling together with natural evaporation or forced drying, there is no longer a liquid film on the surface of the granulated material, and it hardly deforms itself even when it collides with others, and the ability to absorb other things It disappears and the growth of the granules stops. That is, it is a completed stage.

[0010] These series of granulation mechanisms have conventionally been performed in the same granulator even when granulation is performed using a vertical granulator. In the present invention, of this granulation mechanism, after forming the aggregate formed in the nucleation stage using a vertical granulator, the granulation in the growth stage and the completion stage is performed by any granulator. By performing the two-stage granulation method, it has become possible to efficiently granulate an organic raw material having a weak bonding force between particles using only granulation water or steam.

In the present invention, the organic raw material is described in the official standard of ordinary fertilizer specified based on the provisions of Articles 3 and 25 of the Fertilizer Control Law (Act No. 127 of 1950). Stuff, fish cake powder, dried fish fertilizer powder,
Fish-boiled scallop, crustacean fertilizer powder, steamed fish phosphorus and its powder, meat meal powder, meat-and-bone meal, steamed horned meal, steamed horned bone meal, steamed hair powder, dry blood and its powder, raw bone meal, steamed bone meal ,
Steamed leather powder, dried silkworm pupa powder, silkworm pupa oil powder and its powder, silk-spun silkworm pupa waste, soybean oil meal and its powder, rapeseed oil meal and its powder, cottonseed oil meal and its powder, peanut oil meal and its powder, linseed oil Grounds and its powder, sesame oil grounds and its powder, castor oil grounds and its powder, rice bran oil grounds and its powder, other herbaceous vegetable oil grounds and its powder, kapok oil grounds and its powder, corn germ oil grounds and its powder, Tobacco waste fertilizer powder, licorice ground powder, tofu ground dried fertilizer, enjuka ground powder, nitrogenous guano, processed garbage manure fertilizer, fish waste processed fertilizer, dried bacterial cell fertilizer, by-product animal material fertilizer, by-product vegetable fertilizer, It is a mixed organic fertilizer.

In the present invention, the vertical granulator used in the granulation of the first step is a stirring type, which is provided with a stirring shaft projecting upward from the bottom inside a vertical cylindrical mixing tank. It is equipped with a stirrer blade. The granulation method is a first-stage process in which several types of organic raw materials specified by the above-mentioned Fertilizer Control Law are formed into powdery aggregated granulation nuclei. Mixing, while feeding to the granulator
Mixing granulation is performed while spraying water or steam necessary for granulation.

Next, as a second step, the agglomerate (wet) obtained as described above is supplied to an arbitrary granulator, for example, a drum-type granulator, and water necessary for granulation is supplied to the granulator. The growth and sizing are performed while adding steam or the like.

The granulation method of the present invention is as described above. Therefore, the mechanical strength, such as hardness, of the aggregate of core particles formed in the first step is not so important. The vertical stirring granulator used in the first step is provided with a stirring shaft protruding above the bottom inside a vertical cylindrical mixing tank, and several stages of stirring blades are attached to this. The organic powder supplied from above the blade by the high-speed rotation of the blade imparts a large rotational force of rotation and revolution to the powder together with water for granulation, etc., to form fine particles serving as nuclei, In addition, since the generated particles are subjected to the crushing action of the stirring blade, the whole particles are uniform in size, and are suitable for producing fine aggregates. Further, since this vertical stirring granulator also has a mixing action, it is not necessary to use a mixer as a previous step as in the conventional case.

The agglomerates obtained in the first stage are subjected to any granulator in the next second stage, for example, in a drum granulator, with some water for granulation or steam sprayed if necessary. , The supplied agglomerates are rolled, so the strength is high and efficient,
Moreover, it is possible to obtain particles having a highly uniform particle size, and a granular fertilizer that maintains mechanical strength such that the particles are not disintegrated even when supplied to a rotary drier or the like by a conventional method and dried.
(Particle size: 1 to 4 mm) is obtained. Even in actual production, it is possible to obtain a granular fertilizer with a high yield of granulation yield of 80% by weight or more.

[0016]

The present invention will be described in detail with reference to the following Examples, but it should not be construed that the invention is limited thereto without departing from the gist of the present invention. [Example 1] A powder material (total 4 kg) of 50 parts by weight of rapeseed meal, 25 parts by weight of steamed bone meal, and 25 parts by weight of fish waste processing fertilizer is rotated at a rotation speed of 300 rpm.
The mixture was supplied to a vertical stirring granulator having a depth of 35 cm and a depth of 35 cm, and a granulation operation (primary granulation) was performed for about 8 minutes while adding granulation water. About half of the obtained cohesive wet granular material was air-dried and sieved with a 5-mesh and 16-mesh Tyler standard sieve to obtain granules having a product size of 5 to 16 mesh (particle size of 1 to 4 mm). The weight percentage of the product size relative to the dry granules was determined as the product yield. Remaining wet particulate matter with an inner diameter of 76.3
The mixture was supplied to a pan-type granulator having a depth of 19 cm and a depth of 19 cm, and a granulation operation (secondary granulation) was performed at a rotation speed of 23 rpm for 3 to 5 minutes while adding granulation water. A part of the obtained granular secondary granulated product was collected, and rotated by a rotary dryer having an inner diameter of 38 cm and a length of 250 cm at a rotation speed of 5 rpm, an inlet hot air temperature of 230 ° C, an outlet hot air temperature of 110 ° C, and an outlet product temperature of 80 ° C. , And the moisture (% by weight), the product yield (% by weight), and the hardness (kg) were determined using a Kiya type hardness meter. Table 1 shows the results. In addition,
The water content of each raw material used was rapeseed meal 11.0% by weight, steamed bone meal 4.0% by weight, and fish waste processed fertilizer 10% by weight. (Method of measuring water) 2 to 5 g of an analysis sample is accurately taken in a flat weighing bottle (diameter 5 cm, height 3 cm), dried at 75 ° C for 5 hours, weighed accurately, and the weight loss is taken as moisture.
(Measurement method of hardness) Measuring device: Kiya type hardness meter Measuring method:
10 to 2 with average particle size of particle size distribution from sample
Zero grains are arbitrarily taken out, measured with a granule hardness meter, and the average value is defined as hardness (Kg / grain) (all agricultural standards: by the hardness measuring method of granular fertilizer).

[0017]

[Table 1]

Example 2 50 parts by weight of steamed leather powder, 30 parts by weight of steamed bone powder, 10 parts by weight of fish waste processed fertilizer, 1 rapeseed meal
0 parts by weight of the powder raw material (4 kg in total) was granulated using the apparatus shown in Example 1 under the same conditions. The results are shown in Table 2. The water content of each raw material used was steamed leather powder 12.
0% by weight, steamed bone meal 4.0% by weight, fish waste processing fertilizer 1
0.0 wt% and rapeseed meal were 11.0 wt%.

[0019]

[Table 2]

[Comparative Example] 50 parts by weight of rapeseed meal, steamed bone meal 2
5 parts by weight and 25 parts by weight of fish waste processing fertilizer (2.3 kg in total) of powdered raw material in a bread granulator without adding granulating aids such as molasses and the like, while adding granulation water, 3 at 23 rpm
After performing granulation operation for 6 minutes (primary granulation only, 5 tests), the yield of the product size (1 to 4 mm) after natural drying was 41% at the maximum and about 35.4% on average. there were.

[0021]

According to the granulation method of the present invention, uniform core particles are produced in the first stage in a specific granulator, and the particles are formed in the second stage in another granulator. By using the particles grown in the granulation step, it is possible to efficiently granulate the granular material of the organic fertilizer having high hardness at low cost.

Claims (3)

(57) [Claims] 1. The method of claim 1, wherein when the organic fertilizer is granulated, the powder of the organic raw material is supplied to a stirring granulator to form a particle nucleus.
Step process, continuously supplying the particle nuclei to a rolling granulator,
A granulation method of an organic fertilizer, wherein a granulated product having a particle size of 1 to 4 mm is obtained by a second step of granulating, growing and sizing, and a drying step. 2. The granulated product is dried at a rate of 1.0 kg / particle or less.
2. The method for granulating an organic fertilizer according to claim 1, which has the above hardness. 3. The granulated product is obtained at a yield of 80% by weight or more.
A method for granulating an organic fertilizer according to claim 1 or 2.