JPS5820790A - Manufacture of granular fused phosphate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for producing granular molten phosphorus fertilizer, more specifically, a method for producing granular molten phosphorus fertilizer, and more specifically, a method for producing granular molten phosphorus fertilizer, which includes a method for granulating molten phosphorus fertilizer, a molten phosphorus fertilizer hydrate, a molten phosphorus fertilizer pulverized product, and a Na-type phosphorus fertilizer. This invention relates to a method for producing granular fused phosphorus fertilizer with excellent water disintegrability, which is granulated by adding an aqueous solution of ma salt of carboxymethyl cellulose to a mixture with bentonite.

18M phosphorus fertilizer is produced by drying and sieving molten phosphorus granules, and is commercially available as a sand-like product with particles of 2,000 μm in diameter. It is a well-balanced plant nutrient and is preferred as a soil improvement material.

However, in recent years, mechanical spreading of fertilizer using a broadcaster and bulk blending have become popular, and granular fused phosphorus fertilizer suitable for these applications is required, and various proposals have been made for granulating this fertilizer. For example, there is a method of using an aqueous solution of pulp waste liquid, densified acid, nitrofumic acid, etc. as a binder, but if these are used alone, the amount used is large, the process becomes complicated, it becomes too expensive, or it causes crawling and storage. It is not strong enough to withstand such things.

There is also a method of granulating molten phosphorus granules using a solid substance such as bentonite or potassium silicate alone as a binder, but even if 5 to 20 g of bentonite molten phosphorus is used, the granulated product will not The hardness is only about 0.5 kg/cIna, and in addition, the effective phosphoric acid component is greatly reduced, and even if potassium silicate is used as a binder, it is too expensive to be used as a fertilizer.

In addition, in recent years, molten phosphorus fertilizer has been sold as a mixed phosphorus fertilizer under the name of Dublin, which is used as part of the fertilizer raw material, but phosphoric acid solution is added to the molten phosphorus fertilizer to cause a negative effect, or molten phosphorus fertilizer is used as a mixed phosphorus fertilizer. It is a mixed phosphorous fertilizer that is made by mixing phosphoric acid and heavy superphosphate lime and granulating it with water or an acid solution, but it is different from granular melted phosphorous fertilizer. The present inventors have conducted extensive research on the production of powdered molten phosphorus fertilizer, which is excellent as a soil improvement material and is easy to sow and has good disintegration properties in water. By mixing phosphorous fertilizer and finely pulverized material in an appropriate ratio, and granulating the mixture with highly swellable Na-type bentonite and Na salt of carboxymethyl cellulose,
Water-insoluble fused phosphorus that has enough strength to withstand transportation and storage; water-disintegrable powdered phosphorus that is necessary for smoke to be absorbed in the root zone of crops in the soil. He discovered a method for producing fertilizer.

That is, in the present invention, when granulating molten phosphorus fertilizer to produce powdered fused phosphorus fertilizer, 100 parts by weight of granulated molten phosphorus fertilizer and 150 parts by weight of pulverized molten phosphorus fertilizer granulated material are used. Powdered fused phosphorus fertilizer that passes 90% by weight or more through the sieve 20 to 10
0 parts by weight of Na-type bentonite 1 to 6
% by weight, and then, based on 100 parts by weight of these mixtures, Ua salt 0,1-Q of carboxymethyl cellulose
It is characterized in that 5 parts by weight is added as an aqueous solution with a viscosity of 2000 cps or more, kneaded, and granulated.

The present invention will be explained in more detail below. Used in the present invention,
Molten phosphorus granules are amorphous materials obtained by discharging the mixed raw materials melted in an open hearth or electric furnace outside the furnace and pulverizing them. It differs depending on the operating conditions and fracking conditions and equal pressure. An example of the particle size distribution is shown on a weight basis: 2'000 to 1000μ is 10 to 20 inches, 1000 to 590μ is 20 to 50 inches, 5
90-150μ is 30-60chi, 150μ or less is 1-5
%.

Next, the powdered fused phosphorus fertilizer used in the present invention is obtained by further pulverizing the above-mentioned fused phosphorus granules, or by passing the by-product fine powder through a 150-mesh sieve (
104μ) was crushed to pass 90 inches or more.

Next, the Na@l bentonite used in the present invention has excellent swelling properties with water, and is pulverized so that 90% of the bentonite passes through a 250-mesh sieve (61μ). . This is made by adding 20 parts by weight of the above-mentioned molten phosphorus granulate and powdered molten phosphorus to f1100 parts by weight.
In addition to acting as a binder when mixed in an amount of ~100 parts by weight, it also exhibits swelling properties when in contact with water, so it serves to impart disintegration properties when the granulated product is used as fertilizer.

The amount of Na-type bentonite added is 5 to 5% by weight, preferably 1 to 3% by weight, based on the molten phosphorus fertilizer mixture.

To 100 parts by weight of the raw materials explained above, 0.1 to 100% of Na salt of carboxymethyl cellulose (hereinafter referred to as OMC) is added.
6 parts by weight is used as an aqueous solution. It is appropriate to use an aqueous solution with a concentration of about 1 to 4 weight % and a viscosity of 2000 CpB or more (25° CB type viscometer).

Next, a specific manufacturing method of the present invention will be explained. .

First, add 150 mesh (1) 4μ to the molten phosphorus fertilizer water.
Mix finely pulverized powdered molten fertilizer so that it is more than 90% fertilized, and add 1 to 3% of the molten phosphorous fertilizer to this mixture and add Na-type bentonite that passes 90% of 250 mesh (61μ). Add OMO having a viscosity of 500 cps or more (25° OB type viscometer) to this, and add an amount equivalent to 0.1 to 0.3 of the molten phosphorus fertilizer mixture to 2 to 4 chips in advance. After adding and kneading as a viscous liquid dissolved to a certain concentration and granulating it to the required size using a dish-type granulator, the temperature is 100-110℃.
1 hour flJ'l dry L, particle size of 4-1m/m 80
Powdered fused phosphorus fertilizer can be obtained with a viscosity-forming yield of 1 or more.

As explained above, the present invention is a method of mixing fused phosphorus granules, powdered molten phosphorous, and Na-type bentonite in a predetermined needle, and adding an aqueous solution of KOMO to granulate the mixture.
According to the present invention, the yield of particles with a particle size of 1 to 4 cm is 80% or more, the hardness is 0.9 to 9/an'' or more, and the water disintegration rate is 82q6 or more. It has low production cost, uniform quality,
There is an advantage that the bentonite binder does not disintegrate in the storage cell during transportation, and by spraying water during fertilization, the bentonite binder swells and has a high water disintegration rate.

Next, the present invention will be explained by examples.

Example particle size is 2000-1000μ = 10.3% 1000
~590μ=27.2% 590~105μ=60
．． 8% 105μ or less = 1.7% fused phosphorus fertilizer water granulate and particle size of 300-150μ = 5.5% 150-8
8μ = 5.8chi 88~44μ = 16.9%, 44μ
Below = 71.8% powdered dissolved phosphorus, 88μ or less is 95% Na-type bentonite, and OMO with an average degree of polymerization of 1100
The mixture was mixed and kneaded in the proportions shown in the table and granulated using a dish-type granulator while spraying water so that the moisture content at the time of granulation was 10 to 11 inches. Furthermore, CMOF! A 4% aqueous solution prepared in advance was used.

For comparison, the same procedure as in Example was carried out except that bentonite CMC and n were used alone.

In Examples 461 to 4, bentonite and CMC were granulated in a mixture of a molten phosphorus granulated product and a powdered product.

Granules with a granulation step of 11180 cm or more and a size of 2 m/m or more are transported,
It had enough hardness to withstand storage and had good water disintegration properties.

This was done for comparison. In Comparative Examples 45 to 10, when granulated with only CMO, the water disintegrability was poor, and when granulated with only bentonite, the hardness was low and easily broken. ,
Sample No. 10 was a liquid with a viscosity of 2 and was granulated using a low viscosity OMO of less than 1000 psL, but it was not suitable as a granulating material because a large amount of ungranulated material was generated.

Claims (1)

[Claims] When producing granular molten phosphorus fertilizer by granulating molten phosphorus fertilizer,
A mixture of 100 parts by weight of granulated molten paper fertilizer and 20 to 100 parts by weight of granular molten phosphorus fertilizer that passes through 90% by weight or more of a sieve of 150 mesh obtained by finely pulverizing the granulated molten phosphorus fertilizer. 1 to 3% by weight of Na-type bentonite is mixed with the
Next, to 100 parts by weight of these mixtures, 0.1-0.3 parts by weight of Na salt of xymethyl cellulose was added as an aqueous solution with a viscosity of 2000 cps (25° C. Type B viscometer) or higher, and kneaded. A method for producing granular fused phosphorus fertilizer, which is characterized by granulation.