JP3226937B2 - Granulation method of granular 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 a granular fertilizer using an organic raw material as a main raw material, and more particularly, to a method for granulating a granular fertilizer using a two-stage granulation method in which a granulator is divided into two stages. It relates to a grain method.

[0002]

2. Description of the Related Art Granular fertilizers using organic substances as raw materials are generally prepared by mixing powdered raw materials, adding granulation water and, if necessary, using molasses or the like, as in the case of granular inorganic fertilizers containing no organic substances. Granulation is performed using a granulation aid. On this occasion,
As the granulator, a rolling granulator such as a paddle type, a pan type, and a drum type is generally used. According to this method, as the content ratio of organic matter in the product increases, the granulation yield deteriorates. Therefore, the ratio is limited to at most 60%. Further, in order to produce a product having a high ratio, a granulation auxiliary such as molasses must be used. This not only reduces the fertilizer component of the product, but also causes coloring and bad smell of the product, which has the disadvantage of reducing its commercial value and increasing the cost. In order to increase the mixing ratio of organic raw materials, there is a method of using an extruder or the like.However, equipment costs and operating costs per processing amount are high. Not a target. Furthermore, since the product has a cylindrical shape, there is a problem that it is not suitable for machine fertilization.

[0003]

SUMMARY OF THE INVENTION The present invention provides a method for efficiently producing a high-strength granular fertilizer having no problem of coloring or offensive odor from a raw material having a high content of organic matter, which has heretofore been impossible.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in view of the above-mentioned problems, and as a result, have obtained organic raw materials in advance.
After finely pulverizing, these raw material powders are formed into agglomerated particle nuclei in the first step, which is then grown and sized in a second step using another granulator. The present invention has been found that it is possible to economically granulate a raw material containing a large amount of an organic raw material having poor granulation properties by performing granulation.

That is, according to the present invention, a raw material powder comprising an organic raw material powder and an inorganic raw material powder is supplied to a granulator to form a particle nucleus, and the particle nucleus is continuously formed. The present invention relates to a method for granulating a granulated product having a particle size of 1 to 4 mm by a second stage of supplying to another granulator, granulating, growing, and sizing. Reaches 80% by weight or more.

The granulator used in the present invention is a vertical granulator of a stirring type, a tray type granulator of a rolling type, a drum type granulator, a paddle type granulator and the like. Granulators are widely used for mass production because they have lower equipment costs per processing amount and lower operating costs compared to other granulators such as extrusion granulators and compression granulators. Things.

The mechanism of granulation using these agitation type or tumbling type 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 agglomerates are formed by forming a concave lens-like liquid crosslink, but when this is rolled, the agglomerates are gradually tightened and the voids between the particles are reduced. Since the liquid is still scattered locally, it comes into contact with the small pieces and easily adheres to them 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. The so-called "surface-dried granulated material" has a stronger internal binding force than a granulated material having a large liquid content due to an increase in the capillary force of the caught surface. Furthermore, when the liquid content is reduced by tumbling together with natural evaporation or forced drying, the liquid film no longer exists on the surface of the granulated material, it hardly deforms itself even if it collides with others, and the ability to absorb others It disappears and the growth of the granules stops. That is, it is a completed stage.

Conventionally, a series of these granulation mechanisms have been performed in the same granulator. Of these granulation mechanisms, agglomerates formed in the nucleation stage are taken out, and the growth stage and the completion stage are performed. By performing the two-stage granulation method in which the granulation is performed by another granulator, it is possible to efficiently granulate the organic raw material having a weak bonding force between the particles using only granulation water or steam. became.

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 boiled meal, crustacean fertilizer powder, steamed fish scale and its powder, meat meal powder, meat-and-bone meal, steamed horned meal, steamed horned bone meal, steamed hair meal, 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, a granulator used in the granulation of the first step is a stirring-type or rolling-type granulator. In the granulation method, as the first step, the pulverized organic raw material is supplied to a granulator in order to form an agglomerated granulation nucleus. To obtain an aggregate.

Next, in the second step, the agglomerate (wet) obtained as described above is used as a rolling granulator other than the one used in the first step, for example, a drum type granulator. It is grown and sized while supplying water, steam and the like necessary for granulation to a mill.

The granulation method of the present invention is as described above. Therefore, the mechanical strength, such as hardness, of the aggregated granules serving as nuclei formed in the first step is not so important. First
The wet agglomerated product obtained in the step can be obtained by supplying a small amount of water for granulation and, if necessary, steam or the like in an optional granulator of the following second step, for example, a drum type granulator. Since the agglomerates are agitated or tumbled, they can be efficiently formed into particles having a high strength and a uniform high particle size without adding a granulation aid. It has mechanical strength that does not collapse even when supplied and dried.
It is possible to obtain a spherical granular fertilizer with a 4 mm granulation yield of 80% by weight or more in high yield.

[0015]

The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the scope of the present invention. [Example 1] 36 parts by weight of steamed bone meal, 30 parts by weight of castor meal, 14 parts by weight of by-product animal fertilizer, 4 parts by weight of ammonium sulfate, 4 parts of urea
Parts by weight, 12 parts by weight of sulfuric acid, and 4 parts by weight of a powder raw material (total of 4 kg) are supplied to a vertical stirring granulator having an inner diameter of 35 cm and a depth of 35 cm rotating at a rotation speed of 300 rpm, and granulating water is added for about 8 minutes. A granulation operation (primary granulation) was performed. About half of the obtained coagulated wet granular material was air-dried and sieved with a 5 mesh and 16 mesh Tyler standard sieve to obtain a product size of 5 to 16
Granules having a mesh (particle diameter of 1 to 4 mm) were determined, and the weight% of the product size relative to the total dry granules was determined as a product yield. The remaining wet particulate matter is 76.3 cm inside diameter and 19 cm deep
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 granulated secondary granulated product is sampled and has an inner diameter of 38c.
m, rotation speed 5rpm with rotary dryer of 250cm length
Dry at an inlet hot air temperature of 230 ° C, outlet hot air temperature of 110 ° C, outlet temperature of 80 ° C, and determine its moisture (% by weight), product yield (% by weight), and hardness (kg) with a Kiya hardness meter. I asked. Table 1 shows the results. The water content of each raw material used was 4.0% by weight of steamed bone meal, 10.0% by weight of castor meal, 10.0% by weight of by-product animal fertilizer, 0.2% by weight of ammonium sulfate, 0.3% by weight of urea. %, Sulfated potassium 0.2% 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: 1 having a particle size of average particle size distribution from the sample
0 to 20 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 method of measuring the hardness of granular fertilizer).

[0016]

[Table 1]

Example 2 40 parts by weight of rapeseed meal, 30 parts by weight of steamed bone meal, 20 parts by weight of fish waste processing fertilizer and 10 parts by weight of phosphorous powder (total 5 kg) were mixed at a peripheral speed of 0.2 m / s. Was supplied to a drum-type granulator having an inner diameter of 50 cm and a length of 1 m, which was rotated at, and primary granulation was performed with a residence time of 4 min 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.
The weight percentage of the product size relative to the total dry granules was determined as the product yield. The remaining wet granular material is supplied to another drum type granulator having an inner diameter of 50 cm and a length of 1 m rotating at a peripheral speed of 0.2 m / s, and granulation time is 3 to 4 min while adding granulation water. 2
The next granulation was performed. A part of the obtained granular secondary granulated product was collected, and rotated at 5 rpm with a rotary dryer having an inner diameter of 38 cm and a length of 250 cm, the inlet hot air temperature was 230 ° C, the outlet hot air temperature was 110 ° C, and the outlet product temperature was 80 ° C. , And its moisture (% by weight), product yield (% by weight) and hardness (kg) were determined using a Kiya type hardness meter. Table 2 shows the results. The water content of each raw material used was 11.7% by weight of rapeseed meal, 5.2% by weight of steamed bone meal, 10.2% by weight of fish waste processing fertilizer, and 2.5% by weight of phosphorus.

[0018]

[Table 2]

[Comparative Example] Powdered raw material consisting of 36 parts by weight of steamed bone meal, 30 parts by weight of castor meal, 14 parts by weight of by-product animal fertilizer, 4 parts by weight of ammonium sulfate, 4 parts by weight of urea, and 12 parts by weight of sulfuric acid potassium .3 kg) in a pan-type granulator without granulation aids such as molasses and the like, while adding granulation water at a rotation speed of 23 rpm.
After performing the granulation operation for 6 minutes (primary granulation only, 5 tests), the yield of the product size (1 to 4 mm) after natural drying is 52% at the maximum and about 43.5% on average. Met.

[0020]

According to the granulation method of the present invention, uniform core particles are produced in the first step, and the particles are grown in the second step. % Or more, and a granular fertilizer having high hardness can be efficiently and at low cost with a yield of 80% or more.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-49-91854 (JP, A) JP-A-49-98378 (JP, A) JP-A-2-88483 (JP, A) JP-A-2-98483 69384 (JP, A) JP-A-59-203789 (JP, A) JP-A-49-18657 (JP, A) JP-B-47-32550 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) C05G 1/00 C05F 15/00

Claims (2)

(57) [Claims] 1. A first step of supplying a raw material powder obtained by mixing an organic raw material powder with an inorganic raw material powder to a stirring type or tumbling type granulator to form particle nuclei; It is characterized in that a granulated product having a particle size of 1 to 4 mm is produced by a second step of continuously supplying to another rolling granulator, granulating, growing and sizing. Granulation method of granular fertilizer. 2. The method for granulating a granular fertilizer according to claim 1, wherein the hardness of the granular granules having a particle size of 1 to 4 mm is 1.0 kg / particle or more.