JPS6012311B2 - Granular compound fertilizer - Google Patents

Description

[Detailed description of the invention] The present invention relates to a granular compound fertilizer.

More specifically, the present invention relates to a granular compound fertilizer that contains a hydrophilic nitrogen fertilizer and a potash fertilizer in water and does not float when applied to paddy fields. Imbutylidene diurea, which is a condensate of urea and isobutyraldehyde, is used as a water-soluble nitrogen fertilizer, and this is mixed with potassium fertilizer such as potassium chloride and other fertilizers as necessary, and calcium Granules made from compounds and scale acid are used as a compound fertilizer for top-dressing paddy fields, but when sprayed on paddy fields, they become difficult to dissolve in water as the water-repellent fertilizer components are leached out. The drawback is that some of the fertilizer components tend to float near the water surface.

As a result of extensive research into preventing the levitation of granular compound fertilizers as described above, the present inventors found that when the granular compound fertilizers contain a specific compound, the levitation of fertilizers can be almost completely prevented. , completed the invention.

That is, the present invention aims to provide a granular compound fertilizer that has slow release properties and is particularly suitable for use in paddy fields. A fertilizer mixture mainly consisting of a condensate of poorly water-soluble nitrogen fertilizer and potash is granulated using a calcium compound and a mineral acid, and then an alkali metal salt of alkylbenzenesulfonic acid or an alkali metal salt of alkylbenzenesulfonic acid This is a granular compound fertilizer containing an alkali metal salt.

The present invention will be explained in detail below. In the present invention, the water-soluble nitrogen fertilizer which is a condensate of urea and an aldehyde having a carbon number of 4 or less is a mixture of urea and isobutyraldehyde, normal butyraldehyde, propionaldehyde, crotonaldehyde, acetaldehyde, formaldehyde, etc. It is obtained by reacting with an aldehyde having 4 or less carbon atoms or a mixture thereof, and specifically, imbutylidene diurea, normal butylidene diurea, propylidene diurea, crotonylidene diurea, ethylidene diurea, Examples include condensates of urea and formaldehyde, which have the same solubility in water as imbutylidene diurea.

Typical examples include imbutylidene diurea and crotonylidene diurea, which are commercially available as grain-effective fertilizers. These water-soluble nitrogen fertilizers have a particle size of 0.05 to 3.0, preferably 01 to 2.0. It is best to use something about the size of Gomatsu. Potassium chloride, potassium sulfate, potassium nitrate, etc. can be cited as the additives.

These fertilizers are mixed and then granulated, and if necessary, other fertilizer components may be added, such as urea, water-soluble nitrogenous fertilizers such as ammonium sulfate and ammonium nitrate, ammonium phosphorus, peroxide, filtrate, molten phosphorus, and calcined fertilizers. Phosphate fertilizers such as phosphorus, heavy calcined phosphorus, and magnesium superphosphate, and sources of texture elements such as shelving elements, manganese, and zinc can also be added.

Granulation of fertilizer mixtures is carried out in the presence of calcium compounds and mineral acids.

Calcium compounds include calcium hydroxide, calcium oxide, calcium carbonate, mixtures thereof, or acidic fertilizers containing about 5% by weight or more of calcium as Ca○, such as ferronickel ore or stainless steel ore. , magnesium mineral regulations, etc.

The amount of calcium compound used is
1.0 to 8 as ○. % by weight, preferably from 2.0 to 5
．． % by weight.

If the amount of calcium compound is too small, the effect of preventing floating will be insufficient, and if it is too large, the content of fertilizer components will be low, which is not preferable. Examples of mineral acids include sulfuric acid, phosphoric acid, and nitric acid.

The amount of mineral acid used is 0.5 of the neutralization equivalent of the calcium compound.
-1.3 volume, preferably about 0.7 to 1.2 times the volume. Granulation is usually carried out by blending a fertilizer mixture with a calcium compound, using a drum-type or dish-type granulator, and adding a mineral acid.

The particle size of the granules obtained by granulation is determined by the use of the compound fertilizer and varies from 0.5 to 10 ribs, but for paddy fields, it is generally about 1.5 to 4.5 ribs.

The alkali metal salt or alkali metal salt of alkylbenzenesulfonic acid to be contained in the granular composite fertilizer of the present invention has 6 to 1 carbon atoms and preferably 10 to 14 carbon atoms.
Salts of benzenesulfonic acid having a straight-chain alkyl group with alkali metals such as sodium and potassium, or alkali metals such as calcium, magnesium, and barium are listed, and typical examples include dodecyl Examples include sodium benzenesulfonate.

In order to incorporate an alkali metal salt or an alkali metal salt of an alkylbenzenesulfonic acid into a granular composite fertilizer, it may be added at any stage from production to use of the granular composite fertilizer, for example, before granulating the fertilizer. How to add it to
Methods include adding it to the fertilizer mixture during granulation, or adding it to granules after granulation, but the method of adding it to the fertilizer mixture during granulation is preferred because it is easy to operate and has excellent effects. . The amount of alkali metal salt or alkali metal salt of alkylbenzenesulfonic acid to be contained is 0.05 to 0.5% by weight based on the entire granular compound fertilizer;
Preferably it is about 0.1 to 0.4% by weight.

If this amount is too small, the effect of preventing floating cannot be expected. On the other hand, if there are too many, no special effects can be expected. Furthermore, ``In the method of adding an alkali metal salt or alkali metal salt of alkylbenzenesulfonic acid during granulation or to the fertilizer before granulation, granulation becomes difficult if the amount added is too large. Not preferred. The granular composite fertilizer of the present invention contains slow-release nitrogen fertilizer and potassium fertilizer and does not float in water, so it has great utility value, especially as a fertilizer for top-dressing paddy fields.

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof.

In the examples, "parts" and "%" indicate "parts by weight" and "% by weight," respectively.

Example 1 and Comparative Examples 1-2 Inbutylidene diurea (particle size 0.2-0.7 ribs) Shigeru 6
101 parts of urea, 326 parts of ammonium sulfate, and 242 parts of potassium chloride were mixed and charged into a dish-type granulator.
20% of sodium dodecylbenzenesulfonate (manufactured by Lion Oil ■, product name L-D Spot #50) while being transferred.
After adding 13.4 parts of an aqueous solution and then adding 41 parts of calcium hydroxide, transfer granulation was carried out at 55oC for 6 minutes while adding 56 parts of 70% sulfuric acid.

The obtained granules were dried for 20 minutes at a temperature of 10 mm to a particle size of 1.5 to 4. A granular compound fertilizer from Hiro was obtained.

The results of measuring the hardness and floating rate in water of this granular composite fertilizer are shown in the table below. For comparison, in the above example, sodium dodecylbenzenesulfonate was not added (Comparative Example 1), and calcium hydroxide and sulfuric acid were not added and tumble granulation was performed for 6 minutes (Comparative Example 2). ) results are also listed.

However, in the above table, the hardness indicates the average value of 2 hardness values measured using a Jupiter type hardness meter for willow particles having a particle size of 2.4 to 2.8.

In addition, the water surface surfacing rate is 170 x 22 with 600 secretions of water.
Add 25 ml of the sample granular fertilizer to a 0 x 25 rib vat and leave it at room temperature.After 1 hour and 6 hours of standing,
Those that floated to the surface within the depth were collected and dried, and the percentages relative to the sample granular fertilizer were expressed.

Claims (1)

[Scope of Claims] 1. A fertilizer mixture mainly consisting of a water-insoluble nitrogen fertilizer and a potassium fertilizer, which is a condensation product of urea and an aldehyde having a carbon number of 4 or less, is granulated using a calcium compound and a mineral acid. A granular composite fertilizer comprising granules containing an alkali metal salt or alkaline earth metal salt of alkylbenzenesulfonic acid. 2. The granular composite fertilizer according to claim 1, wherein the content of the alkali metal salt or alkaline earth metal salt of alkylbenzenesulfonic acid is 0.05 to 0.5% by weight based on the granular composite fertilizer.