JPH07157385A - Production of granular fertilizer - Google Patents

Abstract

PURPOSE:To produce a granular fertilizer with enhanced productivity without requiring equipments such as a heating equipment, etc., which shows only small reduction in its cyanamide content at the time of storing it and can provide a field crop with useful components by its only one application and further, can reduce the interparticle segregation of the effective components of the fertilizer even at the time of using a mixed fertilizer contg. plural effective components to enable the uniform fertilizer application to the crop. CONSTITUTION:Calcium cyanamide alone or a mixed fertilizer consisting of calcium cyanamide and at least one fertilizer selected from fused magnesium phosphate fused phosphate, ammonium phosphate and potassium salts is granulated by using urea. At that time, the temp. of a feed fertilizer mixture consisting of the above calcium cyanamide alone or mixed fertilizer and urea or another feed fertilizer mixture obtained by further adding an organic fertilizer to the former feed fertilizer mixture is raised so that the urea is brought into a molten state by the frictional heat generated in the granulating machine without performing any external heating to combine the urea and the other fertilizer components of the feed fertilizer mixture. Thereafter, the feed fertilizer mixture is granulated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing lime nitrogen or granular fertilizer containing it as a main component.

[0002]

2. Description of the Related Art Powdered products are generally used as compounded fertilizers containing lime nitrogen or other fertilizing components.
Partly, a granular type blended product obtained by mixing the granules of the fertilizing ingredient is also commercially available. Powdered products have problems such as fertilizer loss due to scattering during spraying, damage to other crops in the vicinity, and environmental pollution. On the other hand, granular type blended products do not have these problems, but have problems such as segregation of fertilizing components, and it was difficult to uniformly apply the necessary components to agricultural products by spraying once. .

In order to solve this problem, it is known that lime nitrogen is pretreated with water or the like and then granulated (Japanese Patent Application Laid-Open No. 52-150280).
There is a problem that the cyanamide component of about 30% decreases. On the other hand, lime nitrogen or a compound containing it as the main component is 120-
After heating to 140 ℃, add urea to melt and disperse,
There is also a proposal to granulate it under heating (Japanese Patent Publication No. 47).
-13085). According to this method, the above problems due to the water addition method are eliminated, but since heating equipment is required and the heat transfer efficiency of lime nitrogen or a compound containing it as a main component is poor, the equipment becomes large and the production efficiency deteriorates. There is a problem.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems, reduces the reduction of cyanamide components during storage, and can uniformly apply components useful for agricultural crops by one-time spraying, Moreover, even in the case of compound fertilizers containing multiple fertilizers, it is possible to reduce the segregation of fertilizers between the particles and to make it possible to apply fertilizer uniformly without the need for equipment such as heating. The purpose is to increase the production.

[0005]

[Means for Solving the Problems] That is, the present invention provides a mixture of lime nitrogen alone or one or more selected from fused phosphorus fertilizer, calcined phosphorus fertilizer, ammonium phosphate and potassium salt. When granulating using urea, the raw material mixture consisting of the above lime nitrogen alone or the mixture and urea, or the raw material mixture obtained by further adding an organic fertilizer to this raw material mixture is heated by friction heat of the molding machine without external heating. It is a method for producing a granular fertilizer, characterized in that the urea is raised to a molten state by the above, and they are combined and then granulated.

Explaining the present invention in more detail below, the raw material mixture used in the present invention is one kind selected from a mixture of lime nitrogen and urea, fused phosphorus fertilizer, calcined phosphorus fertilizer, ammonium phosphate and potassium salt. Alternatively, it is a mixture of two or more kinds (hereinafter collectively referred to as “molten phosphorus fertilizer etc.”), lime nitrogen and urea, and a mixture of these mixtures further containing organic fertilizers such as oil cake and rice bran. When the molten phosphorus fertilizer or the like is added, it is preferably about 80% by weight or less based on the total of lime nitrogen and the molten phosphorus fertilizer or the like.

The proportion of urea is preferably such that the raw material mixture is contained in an amount of 5 to 30% by weight, and when the amount is less than 5% by weight, the strength of the obtained particles becomes insufficient, and when it exceeds 30% by weight, the fluidity becomes extremely high. And the moldability deteriorates.

The organic fertilizer is used to increase the granulation efficiency when granulating the mixed fertilizer consisting of lime nitrogen alone or lime nitrogen and fused phosphorus fertilizer with urea, and the ratio thereof. Is preferably 20% by weight or less, particularly 5 to 15% by weight in the raw material mixture. The organic fertilizer enhances the granulation efficiency and also acts as a fertilizing ingredient and a soil conditioner.

In the present invention, the raw material mixture is mixed and granulated by a molding machine capable of increasing the temperature to a molten state of urea, that is, about 100 to 140 ° C. by frictional heat without external heating. The molding machine used in the present invention is preferably one capable of performing pressurization and molding at the same time, and as an example thereof, an extrusion molding machine such as a screw type, a rotary porous die, or a rotary blade, a compression roll, or briquetting. It is a compression molding machine for rolls and tablets.

The degree of granulation is 0.5 to 10 mm.
The particle size of is desirable, and the shape is cylindrical, granular,
There are no restrictions as it is in granular form. These adjustments can be performed by the number of times the molding operation is repeated.

[0011]

EXAMPLES The present invention will be described in more detail below with reference to examples.

Example 1 Lime nitrogen (T-N 24.5%, Cy-N 23.6%) 9
An extruder for pressure-molding a raw material mixture consisting of 00 kg and 100 kg of urea by a roller rotating on a circular die (“Disc pelletizer F-5” manufactured by Fuji Paudal Co., Ltd.
Mold ”) allows the temperature of 100 ° C. due to the frictional heat generated when the raw material mixture passes through the die without external heating.
The operation of extruding from a die while forming a molten state was repeated to form pellets of 3 × 10 mm.

After the raw material mixture was charged into the extruder, a proportion of pelletized particles of 3 × 10 mm was measured as a product yield after a lapse of a predetermined time. Further, after 20 minutes, the pelletized product was analyzed and the product hardness was measured by a Kiya type hardness tester, and an average value of n = 4 was calculated. Furthermore, the obtained pellets are polyethylene bags (thickness 0.1
The production rate of 0.1 mm vulgar products when 20 kg was put in 8 mm) and stored in a warehouse was measured. The results are shown in Tables 1 to 3.

Example 2 As a raw material mixture, 283 kg of lime nitrogen and 3 parts of molten phosphorus fertilizer
50 kg, potassium chloride 167 kg and urea 200 kg
Pelletization was carried out in the same manner as in Example 1 except that the above-mentioned product was used.

Example 3 As a raw material mixture, 817 kg of lime nitrogen and 100 k of urea
g and 83 kg of oil cake, except that
Pelletization was performed in the same manner as in Example 1.

Example 4 As a raw material mixture, 283 kg of lime nitrogen and 3 parts of molten phosphorus fertilizer were used.
Other than using 50 kg, 167 kg potassium chloride, 100 kg urea and 100 kg rice bran,
Pelletization was performed in the same manner as in Example 1.

[0017]

[Table 1]

[0018]

[Table 2]

[0019]

[Table 3]

[0020]

EFFECTS OF THE INVENTION According to the present invention, a compound fertilizer containing a plurality of fertilizing components can be applied by reducing the amount of the cyanamide component reduced during storage and imparting a component useful for agricultural crops by one-time application. Even if there is such a granular fertilizer, segregation of fertilizing components between the particles can be reduced and uniform fertilization can be performed, and the productivity can be increased without the need for equipment such as heating.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location C05G 5/00 Z 7537-4H // (C05C 13/00 7:00 9:00)

Claims (2)

[Claims] 1. When granulating lime nitrogen alone or a mixture thereof with one or more kinds selected from fused phosphorus fertilizer, calcined phosphorus fertilizer, ammonium phosphate and potassium salt with urea, Manufacture of granular fertilizer characterized in that a raw material mixture consisting of lime nitrogen alone or a mixture and urea is raised to the molten state of urea by frictional heat of a molding machine without external heating and they are combined and then granulated Method. 2. The method for producing granular fertilizer according to claim 1, wherein the raw material mixture further contains an organic fertilizer.