JPS6012312B2 - granular compound fertilizer - Google Patents

Description

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

Specifically, the present invention relates to a granular compound fertilizer that contains a slow-release nitrogen fertilizer and a potash fertilizer and does not float when applied to paddy fields. As a water-soluble fertilizer,
Using isobutylidene diurea, which is a condensation product of urea and isobutyraldehyde, it is mixed with potassium fertilizer such as potassium chloride and other fertilizers as necessary, and granulated by moat with gypsum. This product is known as a compound fertilizer for top-dressing paddy fields, but when it is sprayed on paddy fields, as the water-soluble fertilizer components elute, some of the fertilizer components that are elutriated by the water are deposited near the water surface. The disadvantage is that it makes it easier to float.

As a result of extensive research into preventing the levitation of the granular compound fertilizers described above, the present inventors have found that when the granules contain a specific compound, the levitation of the fertilizer can be almost completely prevented. Heading The invention has been completed.

That is, the purpose of the present invention is to provide a granular compound fertilizer that is effective for rice fields and is particularly suitable for use in paddy fields. It is a granular compound fertilizer made by mixing an aqueous nitrogen fertilizer, a potash fertilizer, and gypsum in water, which is a condensate, and granulating it, and then adding an alkali metal salt or an alkali metal salt of an alkylbenzenesulfonic acid to the granulate. .

The present invention will be explained in detail below.

The water-soluble nitrogenous fertilizer of the present invention, which is a condensate of urea and an aldehyde having 4 or less carbon atoms, includes urea, isobutyraldehyde, n-butyraldehyde, propionaldehyde, crotonaldehyde, acetaldehyde,
It is obtained by reacting with an aldehyde having a carbon number of 4 or less, such as formaldehyde, or a mixture thereof, and specifically, imbutylidene diurea, normal butylidene diurea, propylidene diurea, crotonylidene diurea, ethylidene diurea, etc. Examples include dendiurea and a condensate of urea and formaldehyde, which has a solubility in water comparable to that of imbutylidene diurea.

Typical examples include imbutylidene diurea and crotonylidene diurea, which are commercially available as grain-effective nitrogen fertilizers. These nitrogen fertilizers that are poorly soluble in water are
It is best to use one with a diameter of about 0.05 to 3, preferably about 0.1 to 2. Examples of potassium fertilizers include potassium chloride, potassium sulfate, and potassium nitrate.

In the granular compound fertilizer of the present invention, fertilizer components other than those mentioned above may be used as necessary, such as urea, ammonium sulfate, water-drop nitrogen fertilizers such as ammonium nitrate, ammonium phosphorus, dosuishi, dosuishi, molten phosphorus, Akatsuki phosphorus, Phosphate fertilizers such as phosphorus phosphoric acid, or sources of trace elements such as shelf elements, manganese, and zinc can also be added.

As the gypsum, anhydrite, hemihydrate gypsum, and dihydrate gypsum can all be used. Industrially, it is advantageous to use gypsum produced as a by-product during phosphoric acid production (phosphoric acid-generated gypsum), or gypsum obtained as a product during flue gas desulfurization (flue gas desulfurization gypsum). The amount of gypsum to be used is preferably 2 to 15% by weight, preferably 5 to 1% by weight, based on the entire granular compound fertilizer. If the amount is too small, the hardness will not be sufficient and only granular compound fertilizer will be obtained that tends to float. On the other hand, if it is too large, the content of fertilizer components will be low, which is not preferable. Granulation is usually carried out by mixing the fertilizer components and gypsum as described above, using a drum-type or dish-type granulator, and transferring the mixture while adding water.

The particle size of the granules obtained by granulation is determined by the use of the granular compound fertilizer, and varies from 0.5 to 10 grains.
For use in paddy fields, it is generally on the 1.5 to 4.5 side.
In the present invention, the alkali metal salt or alkali metal salt of alkylbenzenesulfonic acid to be contained in the granular compound fertilizer includes benzenesulfonic acid having an alkyl group having 6 to 1 carbon atoms and preferably 10 to 14 carbon atoms, and sodium chloride. , salts with alkali metals such as potassium, or alkali metals such as calcium, magnesium, and barium, and a typical example is sodium dodecylbenzenesulfonate.

In order to incorporate an alkali metal salt or an alkaline earth metal salt of alkylbenzenesulfonic acid into a granular composite fertilizer, it may be added at any stage from the production of the granular composite fertilizer to its use, for example, the fertilizer component before granulation. Alternatively, there are methods such as adding it to gypsum, adding it during granulation, or adding it to granules after granulation. It is preferable to add an aqueous solution of about 2 to 3% by weight of the metal salt or alkali metal salt during granulation or to the fertilizer component or gypsum before granulation.

The amount of alkali metal salt or alkali metal salt of alkylbenzenesulfonic acid to be contained is 0.05 to 1. % by weight, preferably from 0.1 to 0
．． It is about 4% by weight.

If this amount is too small, the effect of preventing floating can no longer be expected. On the other hand, if there is too much, no special effect can be expected. In addition, when adding an alkali metal salt or alkali metal salt of alkylbenzenesulfonic acid during granulation or adding it to fertilizer components or gypsum before granulation, if the amount added is too large, granulation will occur. I don't like it to be difficult. The granular composite fertilizer of the present invention contains slow-release nitrogen fertilizer and potassium fertilizer and does not float in water, so it is particularly suitable 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 addition, in the examples, "part" and "
%" indicates "parts by weight" and "% by weight," respectively.

Example 1 and Comparative Examples 1-2 Inbutylidene diurea (particle size 0.2-0.7 side) Shigeru 6
32 parts of ammonium sulfate, 104 parts of urea, 242 parts of potassium chloride, and 8 parts of gypsum dihydrate (phosphate by-product) were mixed and charged into a dish-type granulator, and sodium dodecylbenzenesulfonate (manufactured by Lion Oil Co., Ltd.) was mixed. , Product name L-D
Transfer granulation was carried out at 55:00 for 6 minutes while spraying 15 parts of a 20% aqueous solution of #50) and 8 parts of water.

The obtained granules were tumble-dried at 80 qo for 20 minutes to obtain a particle size of 1.5-4. Obtained granular compound fertilizer on the side.

The results of measuring the hardness and floating rate in water of this granular composite fertilizer are shown in the table below. For comparison, the results obtained when sodium dodecylbenzenesulfonate was not added in the above example (Comparative Example 1) and when dihydrate gypsum was not used (Comparative Example 2) are also shown.

However, in the above table, the hardness indicates the average value of 2 hardness values measured using a Kiya type hardness meter for particles having a particle size of 2.4 to 2.8 ribs. In addition, the water surface flotation rate was determined by adding 25 μm of granular fertilizer to a 170×220×25-sided pad containing 600 μm of water and leaving it at room temperature for 1 hour and 6
After a period of time, those that floated to a depth of 5 skins below the water surface were collected, dried, and expressed as a percentage of the granular fertilizer provided.

Claims (1)

[Scope of Claims] 1. Granules made by mixing a poorly water-soluble nitrogen fertilizer, potassium fertilizer, and gypsum, which is a condensation product of urea and an aldehyde having a carbon number of 4 or less, are mixed with an alkali metal salt of alkylbenzenesulfonic acid. Or granular compound fertilizer containing alkaline earth metal salts. 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 1.0% by weight based on the granular composite fertilizer.