JPS5860686A - Manufacture of phosphatic fertilizer - 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 relates to powdered calcium carbonate or a mixture of one or more alkaline earth metal carbonates such as magnesian calcium carbonate (dolomite), or a mixture thereof and blast furnace slag. A mixture with slag is used as a raw material, and a concentrated phosphoric acid solution and concentrated hydrochloric acid are added to this raw material in a specific ratio, and the mixture is reacted without adding water, thereby separating the water-soluble phosphoric acid content and the soluble phosphoric acid content. This relates to a method for easily and simply producing a phosphoric acid fertilizer that contains both of the above and has a granular form suitable for fertilization through sieving alone, without going through the processing steps of crushing, granulation, and drying. It is.

The present invention relates to powdered calcium carbonate or a mixture of one or more alkaline earth metal carbonates such as magnesian calcium carbonate (dolomite), or the above-mentioned alkaline earth metal carbonates. Concentrations (to
Add 80 g of concentrated phosphoric acid solution and concentrated hydrochloric acid to 1 mole of concentrated phosphoric acid solution, and add 0.05 to 0.20 mole of concentrated hydrochloric acid to 1 mole of concentrated phosphoric acid solution if no blast furnace water slag powder is added. This method of producing a phosphoric acid fertilizer is characterized in that when slag powder is added, it is added at a ratio of 0.05 to 0.30 moles, and the reaction is carried out without particularly adding water.

Phosphate fertilizers include fast-acting phosphate fertilizers whose main ingredient is mostly water-soluble phosphoric acid, such as superphosphate lime and heavy superphosphate lime, and water-soluble phosphate fertilizers, such as dissolved phosphorus fertilizers. Some plants do not contain phosphoric acid, but contain soluble phosphoric acid, which is commonly understood as the acid released from the roots during the growth process of crops.

Water-soluble phosphoric acid moves as necessary during the early stages of crop growth, but due to the iron and aluminum content in the soil, it becomes less soluble and becomes fixed over time, causing it to lose its fast-acting properties. On the other hand, soluble phosphoric acid is slow-release, so it is effective in soils where phosphoric acid is easily fixed, and is particularly effective in soils with a high phosphate absorption coefficient such as volcanic ash soil. Demonstrate. For this reason, phosphoric acid fertilizers containing soluble phosphoric acid are often used as fertilizers for soil improvement, and they are used in conjunction with water-soluble phosphoric acid fertilizers, which have a fast-acting effect. .

In addition, in recent years, phosphoric acid fertilizers that retain both water-soluble phosphoric acid content and <soluble phosphoric acid content have appeared, for example, the following are known.

(1) Manufactured from molten phosphorus fertilizer, superphosphate lime (or heavy superphosphate lime), and phosphoric acid solution.

(2) Manufactured from dissolved phosphorus fertilizer and heavy superphosphate lime or phosphoric acid solution.

(3) Manufactured by heating and decomposing ferronickel slag with a mixed solution of magnesiramular phosphoric acid and sulfuric acid to convert magnesium to magnesium phosphate.

As described above, the present invention is directed to powdered calcium carbonate or a mixture of two or more of alkaline earth metal carbonates such as magnesian calcium carbonate (dolomite), or a mixture of these and blast furnace slag slag. By adding a concentrated phosphoric acid solution and concentrated hydrochloric acid to the powder and reacting it in a predetermined range, it can be used as a phosphoric acid fertilizer.

In this case, a concentrated phosphoric acid solution (concentration 5() to 80%
%) and concentrated hydrochloric acid, the ratio of concentrated hydrochloric acid to 1 mole of concentrated phosphoric acid solution is 0.05 to 0.20 mole in the case of only alkaline earth metal carbonate, and 0.05 to 0.20 mole in the case of using only alkaline earth metal carbonate. When adding powder of Therefore, it is possible to obtain a product that forms granules suitable for fertilization without going through a granulation process or especially a drying process by heating. The reaction between earth metal carbonate and phosphoric acid solution is MeC03-1-2H3P04-+Me(H2PO4)
2-nH2O4002-=-(1) MeCO3+ H3
PO4-+ MeHP04-nH2O-1-Co2. ,
,,, - ・-== (2) (-E formula, Me is C!a, M
(alkaline earth metals such as
Magnesium is produced, these are water-soluble phosphates, (2)
The formula produces dicalcium phosphate and dimagnesium phosphate, which are soluble phosphates.

The reaction rate of (1) and (2) becomes faster when highly sensitive water is contained in the reaction system in the form of a slurry, and the reaction of formula (2) takes priority regardless of the addition period of phosphoric acid. Primarily, soluble phosphates are produced. The reaction of formula (1) does not occur unless the amount of phosphoric acid is 2 moles or more per mole of alkaline earth metal carbonate.

On the other hand, if the amount of water in the reaction system is small,
Regardless of the phosphoric acid content, the reaction of formula (1) takes priority, and if unreacted MeO03 remains, this remaining Mo2O3
and the generated Me(H2PO4)2-nH2O gradually react to generate MeHPO4.nH2O. This second
The reaction in the step is difficult to occur unless there is a certain amount of free water, so by adjusting the water content of the concentrated phosphoric acid solution as described above, that is, adjusting the concentration of the concentrated phosphoric acid solution, MeHP
It may be possible to control the reaction rate to produce O4.nH2O, i.e., soluble phosphate.

This also allows adjusting the concentration of the concentrated phosphoric acid solution and MθC
By adding 2 moles or less of concentrated IJ7 acid solution to 1 mole of O3, it is possible to produce a phosphoric acid fertilizer that simultaneously contains water-soluble phosphoric acid and water-soluble phosphoric acid in the reaction product. It is something that can be done.

On the other hand, the concentration of the concentrated phosphoric acid solution used is an important condition from the viewpoint of processing and handling such as crushing, granulation, drying, product transportation, and storage of the product after the reaction. If the solution is a dilute liquid, it will become a slurry and the reaction of equation (2) above will be agitated, and the product after the reaction will be in the form of a thick liquid, lacking in granulation properties, and free water may be present in the product. Since it contains a lot of 1, heat drying is necessary.

When a highly concentrated phosphoric acid solution is used, the water in the reaction system is consumed by evaporation due to the reaction heat and bonded to the compound as water of crystallization, and the product is formed without any drying process. can do.

However, in the decomposition reaction using only a concentrated phosphoric acid solution, the reaction rate is slow because the powder is insufficiently compatible with the phosphoric acid solution, and the product after the reaction is also viscous. It may be difficult to operate the crushing and granulation basin.

In other words, when a concentrated phosphoric acid solution is simply added to the alkaline earth metal carbonate powder as described above and allowed to react, the carbonate powder reacts with the phosphoric acid bath liquid and decomposes, releasing CO2, resulting in vigorous foaming. , fluidization continues. Thereafter, the reaction progresses gradually and the reaction system becomes more viscous and finally becomes lumpy. This lump is taken out from the storage container, and when aged, it gradually hardens to the extent that it solidifies. However, the reaction of the lumps produced by the reaction proceeds more gradually, and at the same time, the caking property increases and crushing becomes difficult.

On the other hand, when concentrated hydrochloric acid is added to the alkaline earth metal carbonate powder together with a concentrated phosphoric acid bath solution in a predetermined range and reacted as in the method of the present invention, the decomposition reaction of the carbonate is sufficiently carried out. As a result, the amount of undecomposed carbonate is reduced, and the product after the reaction can undergo synchronous motion through a simple processing machine without adding any additives. Particle size is approximately 1 to 4 just by giving it.
It can be made into a granular form suitable for moderate fertilization, and during this time the water content is consumed as water of crystallization in the product, which causes it to solidify moderately hard over time, and therefore is particularly suitable for drying processes. It can be made into a product as is without any modification. .

In the method of the present invention, the decomposition reaction of alkaline earth metal carbonate powder with a concentrated phosphoric acid solution (2. Concentrated hydrochloric acid to be added, i.e., concentration) ~ 1 of a concentrated phosphoric acid solution of 80%
The effects of adding 7.4 moles of concentrated hydrochloric acid to 0.05 to 0.20 moles, or 0.05 to 1.30 moles and causing the reaction to react are significant.

(1) By promoting the decomposition of carbonates and preventing the re-reaction of Ma(H2PO4)2・nH20 contained in the reaction product with unreacted residual carbonates, the composition of the product changes. Reduce.

(2) The granulation property can be improved by reducing the viscosity of the product after the reaction. That is, among the phosphoric acid compounds produced by the reaction of alkaline earth metal carbonate and phosphoric acid, Me(H2PO3)2.nH2O is microcrystalline and viscous, but MeHPO4.nH2O is microcrystalline and viscous.
In No. 20, crystals are relatively developed, and there is no adhesion and cohesion between particles. By adding concentrated hydrochloric acid as shown in this example, MeHPo
Since the production rate of 4.nH2O will increase,
The viscosity of the reaction product can be easily adjusted.

Furthermore, when blast furnace water slag powder is added in addition to alkaline earth metal carbonate powder, the violent bubbling phenomenon of decarbonation gas is alleviated during the decomposition reaction of a mixed acid solution consisting of concentrated phosphoric acid solution and concentrated hydrochloric acid, and the apparent This increases the reaction rate and reduces the viscosity of the product after the reaction, thus significantly shortening the subsequent aging time following the reaction, and the concentration of the concentrated phosphoric acid solution is relatively low. ~60
% can be used. Moreover, at this time, the phosphate of the CaOlMgO component in the sieve furnace water slag also works together with the active ingredient.

A process diagram of the method for producing phosphoric acid fertilizer of the present invention is shown in FIG.

In the above process diagram, A is the raw material alkaline earth metal carbonate powder, B is the blast furnace water slag powder, C is the concentrated phosphate solution with a concentration of 50 to 80%, and D is! I indicates hydrochloric acid, and the raw material may be A alone or A-1-B. In the case of A-1-B, it is preferable that A and B be in approximately the same amount1. Also, in Fig. 1, 1 is reaction, 2 is ripening, 3 is granulation by crushing and rotation, and 4 5 is the sieving process, and 5 is the processing process at each stage of the product.

According to the method of the present invention, a mixture of an alkaline earth metal carbonate powder or an alkaline earth metal carbonate powder and a furnace water slag powder is mixed with a concentrated phosphoric acid bath solution and a concentrated phosphoric acid bath solution under a predetermined acid ratio relationship. A mixed acid solution with sulfuric acid is added to react, and after completion of the reaction, wait for ripening, lightly crush the reaction product, and then granulate it by simply applying rotational motion, and without drying, just sieve it to make the desired product. A product consisting of granules of granular size can be obtained.

The phosphoric acid fertilizer that is the product obtained in this way contains both water-soluble phosphoric acid and soluble phosphoric acid, and the concentration of the concentrated phosphoric acid solution used is low. or if you want to shorten the aging period and proceed to the next step continuously after the reaction is completed, approximately the same amount of blast furnace slag powder is mixed in advance in addition to the alkaline earth metal carbonate powder. It is advantageous to use

The finer the particle size of the raw material powder used in the present invention, the better the reactivity, but a particle size of about 100 to 100 mesh is usually economical, and the concentration of the concentrated phosphoric acid solution used is He admitted that the 80th section is the most preferable.

Also, the concentrated hydrochloric acid used should preferably have a high concentration of 3!5%.
Hydrochloric acid was found to be the most suitable.

The molar ratio of concentrated phosphoric acid solution (H3P04) and concentrated hydrochloric acid (Hcg is 0.05 to 0 Hcz per mol of H3PO4.
．． 20 mol (0.0 when mixed with blast furnace water slag)
Experiments have shown that the addition effect is best when the amount is 5 to 0.30 mol). (1,20 mol (or 0
．． If the amount exceeds 30 mol), the reaction product loses its stickiness, and a binder (granulating agent) is especially required for granulation. 1. When mixing blast furnace water slag, it is desirable to mix the alkaline earth metal carbonate powder with an internal grinding rate of 60% (heavy ridge) of up to 8 degrees, and even when mixed in large quantities, components such as CaO, MgO, For effectiveness, it is possible to use sulfuric acid as an inorganic acid instead of concentrated hydrochloric acid, which has no bitter taste, but using sulfuric acid slows down the reaction rate, and the product after the reaction is more viscous. The effect of adding sulfuric acid to a deep level is not recognized because it is not suitable for granulation.

The present invention will now be explained with reference to Examples and Reference Examples.

Table 1 shows the blending ratio of Tanihara phase used in Examples 1 to 1]11.

In each raw material shown in Table 1, the carbonate of alkaline earth metal is 0. Magnesium calcium carbonate (dolomite) passed through an I49mm standard sieve (CaO34.1%, MgO
17.5%, alkaline content 58.4%) alone or together with blast furnace water slag (5i02:32.
Section 9, Section At20318.2, Ca039.4%, Mg
Ca in a mixture with O5.7%, Fe2O30.8%)
O+MgO or CaO+Mg, Oten (A1203+
The molar ratio of Fθ203) and H3PO4 is 1. ():1.
0 or 1.0: H3P0460 to be 1.1
% phosphoric acid solution or H3P0475g')
, 05 to 0.30, and the content fI
! [t]00t mixer. The mixer is manufactured by Kawada Seisakusho Co., Ltd. and is called the "-S~Zo-Mixer".
A stirring blade was installed at the bottom of the mixing container, and the container was rotated at 500 rpm.As shown in Table 1, a specified amount of each raw material powder was added, and if necessary, the powders were thoroughly mixed, and then the specified amount of A mixture of concentrated phosphoric acid solution and concentrated hydrochloric acid is added, and the stirring blade of the mixer is rotated and stopped for a short time to start the reaction.

The contents undergo a vigorous decarboxylation reaction and foam. After a while, the foaming phenomenon subsides 1. At this stage, the reaction is continued while the stirring blade of the mixer is continuously rotated for several minutes.

The contents gradually become viscous and the load on the mixer increases.

At this point, the rotation of the stirring blade is temporarily stopped, and the reaction product is allowed to stand for several minutes, and then further aged at room temperature for several hours to harden the reaction product.

The aged reaction product is crushed again by rotating the stirring blade of the mixer, and at the same time it is granulated, and the particle size is 1 to 1.
When the granules of 4 gourds were obtained, the stirring blade was stopped and the contents were taken out from the mixer. After taking out, the contents were simply sieved and used as a product without any particular drying.

As can be seen from Table 1, when dolomite powder was subjected to a decomposition reaction using only a 75% concentrated phosphoric acid solution as in Example 1, the viscosity of the reaction product was high; It took a long time of 24 hours or more to ripen the grain, and furthermore, the decomposition reaction continued gradually, making it difficult to commercialize the product.

Therefore, this Example 1 is a reference example of 3°, whereas the molar ratio of concentrated hydrochloric acid to HCl, /')13PO4 is 11.0.
In the case of Example 2 and Example 3 in which 5 and 0.20 were added, the viscosity of the reaction product decreased, and the aging time was about 6 hours, and the crushing and granulation could be performed well. .

In addition, in the case of Example 4 in which concentrated hydrochloric acid was added at a molar ratio of HC1/H3PO4 of 0.30, the viscosity of the reaction product was extremely reduced, and granulation was not possible in that one trench1. Example 4 is a reference example.

In Example 5, in which blast furnace water slag powder was added as a raw material to dolomite powder, the aging time for crushing and granulation was sufficient for about 1 to 2 minutes, but the viscosity of the reaction product was slightly high. Therefore, it was difficult to obtain a product with a relatively fine particle size of 1 to 4 square centimeters.

Compared to Example 5, in the case of Example 6, in which the reaction was carried out by adding concentrated hydrochloric acid at a molar ratio of HC1/H3PO4 of 0.30, the entire process was performed well and a product with a particle size of 1 to 4+m++ was obtained. I was able to do that. .

On the other hand, in the case of Example 7 in which a concentrated phosphoric acid bath solution with a concentration of 60% was used, the amount of water contained in the reaction system was excessive and a suitable granular product could not be obtained. Therefore, as in Example 8, when blast furnace water slag powder was mixed with a pair of dolomite powder at a ratio of 1:1, the reaction product was not crushed or granulated after aging for 5 to 6 minutes after the reaction. Although it is possible to some extent, crushing and granulation (
- It is difficult to obtain a product with a particle size of 1 to 4 degrees, and it tends to be large particles. Therefore, Examples 7 and 8 are reference examples.

In Examples 9 and 10, the added concentrated hydrochloric acid worked effectively and it was possible to obtain products with a particle size of 1 to 4 degrees.

In Example 11, the amount of concentrated phosphoric acid solution is CaO10Mg○+! The molar ratio of T (At203 +Fe203)/H3PO4 was increased to 1.1 to increase the proportion of the phosphoric acid component in the product. In this example, as in Examples 2, 3, 9, and 1o, all steps proceeded without any problems, and a product with a particle size of 1 to 4 mm was obtained without any drying process. Ta.

Analysis of these products after production (target j
,・For the granulation property, combine ♂ku-2 with 7 and 7tζ
(7.1°) At the same time as the soil analysis, we fixed the substances present in the products by X-ray diffraction, and found that ca(H2PO,), -H2O
, CaHPO4, Mg(H2PO4)2.2) (20,
MgHPO4・3H20! It was possible to recognize the L product.

Oa in products manufactured with mixed acid of phosphoric acid and hydrochloric acid
The diffraction peak of (H2PO4)2.H2O became smaller as the concentration of hydrochloric acid increased, the diffraction peak of Ca)iPO4 became sharper, and at the same time the diffraction peak of unreacted dolomite became smaller4, while blast furnace water For products manufactured using raw materials mixed with slag slab powder, A4PO4-:
3) (20) Formation of aluminum phosphates such as FePO4-3H20 and iron sulfate substrates could not be detected by pot X-ray diffraction.

Also, in order to test the component stability of some products including the obtained products, a temperature of 35° C1 relative humidity of 90° C.
After being left in a constant temperature and humidity chamber for 30 days, each component was measured and the results shown in Table 3 were obtained. Calcium carbonate) decreased slightly, and the progress of the degradative reaction could be observed, but the change h1 for each component was extremely small and negligible.

[Brief explanation of drawings]

FIG. 1 is a systematic diagram of step 7 of manufacturing the phosphoric acid fertilizer of the present invention. Patent Applicant: Saakashi Lime Industry Co., Ltd. Procedural Amendment November 2, 1980 To the Commissioner of the Patent Office (To the Examiner of the Patent Office) 1. Indication of the case 1981 Patent Application No. 158366 2. Name of the invention Acid fertilizer manufacturing method 3, Relationship with the case of the person making the amendment Applicant name: Murakashi Lime Industry Co., Ltd. 4, Agent address: 1-1-5 Minami-Aoyama-chome, Minato-ku, Tokyo Date of amendment order (Voluntary) (Delivery date) Showa year, month, day (1), the description of "Claims" from the 4th line of the 1st chapter of the specification to the 1st line of the 2nd chapter of the specification is corrected as shown in the attached sheet. . (2) Delete ``Crushing and granulation'' on line 10 of the second specification. (3) Delete ``Only by sieving'' from lines 11 to 12 of the second specification. do. (4) Correct the statement "On the other hand, the product after the reaction - 1111 may be difficult" from line 8 to line 4 of the 8th page of the specification as shown below. . "On the other hand, the concentration of the concentrated phosphoric acid solution used is important from the viewpoint of handling of the product after the reaction, such as crushing, granulation, drying, product transportation, and storage. If it is a liquid, it becomes a slurry, and the reaction of equation (2) above takes priority, and the product after the reaction has relatively developed crystals, and there is no adhesion and cohesion between particles, so the granulation property is low. In addition, the product contains a large amount of free water, requiring a drying process.On the other hand, when a highly concentrated phosphoric acid solution is used, the water in the reaction system is removed during the reaction. It is consumed by evaporation due to heat and bonded as water of crystallization in the compound, and can be made into a product without going through a drying process.However, in a decomposition reaction using only a highly concentrated concentrated phosphoric acid solution, the powder and the phosphoric acid solution are If the contact with the powder is insufficient, the reaction rate will be slow, and the product after the reaction will be highly viscous, making subsequent crushing and granulation operations difficult. 5), “Moreover” in line 13 of page 8 of the specification is corrected to “even thereafter” 8 (6), “Me (H3P03)” in line 2 of page 10 of the specification
2" should be corrected to "Me(H2PO4)2]. (7) - On page 11, line 14 of the specification, "concentrated sulfuric acid" should be corrected to "concentrated hydrochloric acid." (8), Specification No. 15, line 11 r HC: t75
Correct J to "Hcta". "2. Claim (1), powdered carnoum carbonate or a mixture of one or more alkaline earth metal carbonates such as magnesian calcium carbonate (dolomite) at a concentration of 50 to 80%. A concentrated phosphoric acid solution and a-uniform acid are reacted by adding a-hydrochloric acid at a ratio of 0.05 to 0.20 mol per 1 mol of the concentrated phosphoric acid solution, especially without adding water. (2) Powdered calcium carbonate or magnesian calcium carbonate (dolomite)
A concentrated phosphoric acid solution with a concentration of 50 to 80% and concentrated hydrochloric acid are added to a mixture of one or two carbonates of alkaline earth metals such as -F and blast furnace water slag powder. Add 0.05 to 0.0% hydrochloric acid to #1 mole of concentrated phosphoric acid solution.
Added at a ratio of 30 mol, without particularly adding water,
Method 1 for producing phosphoric acid fertilizer characterized by reaction
．． ” Procedural amendment - Written March 2, 1980, Director of the Patent Office (Examiner of the Patent Office) ■, Small case indication Showa Leap Year Patent Application No. 158366 2, Title of invention Process for manufacturing phosphoric acid fertilizer 3, Amendment Relationship with the case of a person who does
Description 1, Title of the invention: Process for producing phosphoric acid fertilizer 2, Claims (1), 1 of alkaline earth metal carbonates such as powdered calcium carbonate or magnesia calcium carbonate (dolomite) Species or mixtures of two or more species with H3PO4 concentration
80 person in charge! ! A phosphoric acid solution characterized by adding a condensed phosphoric acid solution and hydrochloric acid at a ratio of 0.05 to 1.20 mol to 1 mol of concentrated phosphoric acid solution to give a reaction (2) Powdered Cal/Rum carbonate or one kind of alkaline earth metal carbonate such as 1° Cal/Um decacarbonate (dolomite) or more than 2ft1! 2 and blast furnace water slag powder with H3PO4 concentration of 5.
A phosphoric acid substance characterized by reacting a 0 to 80% concentrated phosphoric acid solution and hydrochloric acid by adding hydrochloric acid at a ratio of 0 to 15 to 0.30 mol per 1 mol of the concentrated phosphoric acid solution. Method for producing fertilizer. 6. Detailed Description of the Invention The present invention provides a method for producing fertilizer using one or a mixture of two or more carbonates of alkaline earth metals such as powdered calcium carbonate or magnesium carbonate (dolomite). , or a mixture of these and blast furnace water slag as a raw material (12), and a concentrated phosphoric acid solution and hydrochloric acid are added to this raw material in a specific ratio and reacted, thereby changing the water-soluble phosphoric acid content and the <soluble phosphoric acid content. This relates to a method for easily and simply producing a phosphoric acid fertilizer which contains both of the following and which exhibits a granular form suitable for fertilization without subjecting the treated product after the reaction to any particular drying process. The present invention is directed to one or more mixtures of alkaline earth metal carbonates such as powdered calcium carbonate or magnesian calcium carbonate (dolomite), or the above-mentioned alkaline earth metal carbonates. A concentrated phosphoric acid solution with an H3PO4 concentration J) ~ 8o% and hydrochloric acid were added to a mixture of one or more carbonates and powdered blast furnace water slag to 1 mole of the concentrated phosphoric acid solution. On the other hand, hydrochloric acid is added at a ratio of 0.05 to 0.20 mol when blast furnace slag powder is not added, and 0.05 to 1.30 mol when blast furnace slag powder is added. This is a method for producing a phosphoric acid fertilizer, which is characterized by reacting the phosphoric acid fertilizer. Fast-acting phosphoric acid fertilizers and fertilizers that do not contain water-soluble phosphoric acid like dissolved phosphorus fertilizers, but contain soluble phosphoric acid that dissolves in the acid released from the roots during the growing process of crops. Water-soluble phosphoric acid has a safe effect during the early stages of crop growth, but due to iron and aluminum content in the soil, it becomes less soluble and becomes fixed over time. On the other hand, soluble phosphoric acid is slow-release, so it is effective in soils where phosphoric acid is easily fixed, especially in volcanic ash soils, which have a low phosphate absorption coefficient. For this reason, phosphoric acid fertilizers containing soluble phosphoric acid are often used as fertilizers for soil improvement. In addition, in recent years, phosphate fertilizers that retain both water-soluble phosphoric acid content and water-soluble phosphoric acid content have appeared, for example, the following are known: . (1) Manufactured from molten phosphorus fertilizer, superphosphate lime (or heavy superphosphate lime), and phosphoric acid solution. (2) Manufactured from dissolved phosphorus fertilizer and heavy superphosphate lime or phosphoric acid solution. (3) Manufactured by heating and decomposing magnesium with a mixed solution of magnesiramular phosphoric acid and sulfuric acid in ferronickel slag to change magnesium to magnesium phosphate. Or a mixture of one or more alkaline earth metal carbonates such as dolomite, or a mixture of them with powdered blast furnace slag, concentrated phosphoric acid solution and hydrochloric acid. By adding and reacting a predetermined amount of CaO and MgO in the powdered mixture, the CaO and MgO components in the powdered mixture are activated as calcium phosphate and magnesium phosphate and used as a phosphate fertilizer. In this case, when decomposing alkaline earth metal carbonate powder with acid, a concentrated phosphoric acid solution (a degree 50 to so%
) and hydrochloric acid, the ratio of hydrochloric acid to 1 mole of concentrated phosphoric acid solution is (1
,05 to 0.20 mol, or 0.05 to 0.05 when blast furnace water slag powder is added. By reacting in addition to the ratio of +o mol, the product after the reaction can be simply mechanically crushed, and at the same time only a slight rotational movement can be applied, so that it can be heated without going through a granulation process. It is possible to obtain a product that exhibits a granular shape suitable for fertilization without going through a drying process. The reaction between a carbonate of an alkaline earth metal such as calcium or magnesium and a phosphoric acid solution [5 is MeCO3+2H3PO4→Me(H2PO4)2・n
H2O+CO2...(1)MeCO3-)-H3P0
4-+MeHPO4-nH20+Co□-=-, (2
) (in the above formula, Me ij Ca, an alkaline earth metal such as Mg), which can be represented by (1) and (2), and the (1
) formula produces phosphoric acid-lime and phosphoric acid-magnesium, which are water-soluble phosphates, and formula (2) produces dicalcium phosphate,
Disodium phosphate is formed and these are soluble phosphates. The reaction of equations (1) and (2) above is faster if a large amount of water is present in the reaction rate, and the reaction of equation (2) takes priority regardless of whether phosphoric acid is added or not. 7. Furthermore, if excess phosphoric acid remains, the generated <soluble Me
HPO4・n H20 and phosphoric acid further react to form MeHP04-nH2O-1-H3PO4-) Me
By the reaction mechanism (H2PO4)2-nH2O, ra
e(H,,po4)2·nH2O is generated. On the other hand, when the amount of water in the reaction system is small, the reaction of equation (1) takes priority regardless of whether phosphoric acid is added, and if unreacted MeCO3 remains, this residual MeCO3
and the generated Me(H2PO4)2-nH2O gradually react to generate MeHPO4.nH2O. This second stage reaction is difficult to occur unless free water is present (1). Therefore, by adjusting the water content of the concentrated phosphoric acid solution, that is, adjusting the concentration of the concentrated phosphoric acid solution, MeHPO4・nH2O, that is, <soluble It may be possible to control the reaction rate for producing phosphate. This makes it possible for water-soluble phosphate to remain in the reaction product even if the reaction product is heated. On the other hand, from the viewpoint of processing and handling of the product after the reaction, such as crushing, granulation, drying, transportation and storage of the product, the concentration r1 of the concentrated phosphoric acid solution used is important, and the phosphoric acid solution When is a dilute liquid, it becomes a slurry, and the reaction of equation (2) above takes precedence (2. After the reaction, the product has relatively developed crystals (7. Because there is no adhesion and aggregation between the particle phases q) ,
It lacks granulation properties and contains a large amount of free water in the product, requiring a drying step. On the other hand, when using a highly concentrated phosphoric acid solution,
During the reaction, water in the reaction system is consumed by reaction heat (・'), evaporation, and binding as water of crystallization in the compound, and the product can be produced without any particular drying process. In a decomposition reaction using only a highly concentrated phosphoric acid solution,
The contact between the powder and the phosphoric acid solution is insufficient, resulting in a slow reaction rate, and the product after the reaction is highly viscous, making subsequent crushing and granulation operations difficult. It is. That is, if only a concentrated phosphoric acid solution is added to the alkaline earth metal carbonate powder as described above and allowed to react, the carbonate powder reacts with the phosphoric acid solution and decomposes, releasing CO2, resulting in vigorous foaming. Fluidize. Thereafter, the reaction progresses gradually, and the reaction system increases in viscosity [2] It finally becomes a lump (1) The lump is taken out from the container, and as it ages, it gradually hardens to the extent that it solidifies. However, the reaction of the lumps produced by the reaction proceeds gradually thereafter, and at the same time, the caking property increases and crushing becomes difficult. On the other hand, when a predetermined amount of hydrochloric acid is added to the alkaline earth metal carbonate powder together with a concentrated phosphoric acid solution as in the method of the present invention, the decomposition reaction of the carbonate is sufficiently carried out, resulting in carbonation. The amount of undecomposed salt decreases,
In addition, the product after the reaction is processed without adding any additives.
Utilizing the appropriate adhesiveness of the reaction product, it is possible to make it into granules suitable for fertilization with a particle size of approximately 1 to 4 mm by simply applying rotational motion through a simple processing machine, and it also contains 7 particles in between. The water is consumed as water of crystallization in the product, and as a result, the product solidifies appropriately over time, and can therefore be used as a product as it is without any particular drying process. In the method of the present invention, during the decomposition reaction of alkaline earth metal carbonate powder with a concentrated phosphoric acid solution, 0.05 to 0. .20 mol, 0.05~
The effects of reacting in addition to the ratio of 0.30 mol include the following points. (1) Promote the decomposition of carbonates 1 - Change the composition of the product by preventing re-reaction between Me(H2PO4)2・nH2O contained in the reaction product and unreacted residual carbonate. Make it a little less. (2) Pelletability can be improved by lowering the viscosity of the product after reaction. That is, among the phosphoric acid compounds produced by the reaction of alkaline earth metal carbonate and phosphoric acid, Me(H2PO4)2.nH2O is microcrystalline and viscous;
The crystals of O are relatively developed, and there is no adhesion and aggregation between the particles3.In this way, by adding hydrochloric acid, MeHPO4・n
Since the production rate of H2O increases, the viscosity of the reaction product can be easily adjusted. Furthermore, when blast furnace water slag powder is added in addition to alkaline earth metal carbonate powder, the violent foaming phenomenon of decarbonation gas is alleviated during the decomposition reaction of a mixed acid solution consisting of concentrated phosphoric acid solution and hydrochloric acid, and the apparent This increases the reaction rate and reduces the viscosity of the product after the reaction, thus significantly shortening the subsequent aging time following the reaction, and the concentration of the concentrated phosphoric acid solution is lower than 50%. 60%
It can be used up to a certain degree. Moreover, at this time, phosphoric acid and salts of CaO and MgO components in the blast furnace water slag also function as effective ingredients. The process diagram of the method for producing phosphate fertilizer of the present invention is shown in Figure 1.1 In the process diagram above, A is the raw material alkaline earth metal carbonate powder, and B is the blast furnace slag. Slag powder, C is concentrated phosphate solution with a concentration of 50-80%, D is hydrochloric acid,
The raw material may be only A or A and B. A-
In the case of 1-B, it is preferable that A and B be in approximately the same amount. In FIG. 1, ] is the reaction, 2 is ripening, 3 is granulation by crushing and rotation, 4 is sieving, and 5 is the treatment process at each stage of the product. According to the method of the present invention, a concentrated phosphoric acid solution and hydrochloric acid are added to a mixture of alkaline earth metal carbonate powder or alkaline earth metal carbonate powder and blast furnace water slag powder under a predetermined working ratio relationship. The mixed solution is added and reacted, and after the reaction is completed, the reaction product is lightly crushed after aging, and then granulated by simply applying rotational motion, and granules of the desired ψ particle size can be produced by simply sieving without drying. A product consisting of can be obtained. The phosphoric acid fertilizer obtained in this way contains both water-soluble phosphoric acid and soluble phosphoric acid, and the concentration of the concentrated phosphoric acid solution used is low. In this case, or if you want to shorten the aging period and move on to the next step continuously after the reaction is completed, approximately the same amount of blast furnace slag powder is mixed in advance in addition to the alkaline earth metal carbonate powder. It is advantageous to use The finer the particle size of the raw material powder used in the present invention, the better the reactivity, but the particle size of about 50 to 100 mesh is usually the most effective, and the concentration of the concentrated phosphoric acid solution used is 50 to 80%. was found to be the most preferable. Also, it is desirable that the hydrochloric acid used be of high concentration.
It was found that 5% hydrochloric acid was most suitable. The molar ratio of concentrated phosphoric acid solution (I(3PO4) and hydrochloric acid (HCt) is 0.05 to 1 mole of H3PO4 for Hot.
0.20 mol (0.20 mol if blast furnace water slag is mixed)
It has been experimentally found that the addition effect is best when the amount is 0.05 to 1.30 mol. When the amount exceeds 0.20 mol (or 13.30 mol), the reaction product loses its stickiness, and the binder (granulating agent) is especially safe for granulation. (For small amounts below 15, the addition of local acid υ1
1 effect cannot be obtained. It is desirable to mix blast furnace water slag with carbonate powder of alkaline earth metals (up to about 1 in. 1 in 7 increments).
Even if mixed with water, it has no meaning in activating components such as CaO, MgO, etc. 6. It is possible to use sulfuric acid as an inorganic acid instead of hydrochloric acid, but if sulfuric acid is used, the reaction rate will be slow. Moreover, the product after the reaction becomes even more viscous and unsuitable for granulation, so adding sulfuric acid will reduce its effectiveness.
There are no Mera 71. Next, the present invention will be explained with reference to Examples and Reference Examples. Table 1 shows the proportions of each raw material used in Examples 1 to 11. In each raw material 1 shown in Table 1, magnesium carbonate (dolomite) (Ca, 034.1%, M
Blast furnace water slag (810□ 32.9, A/12o 318.2, CaO39.4%, Mg0
5.7%, H in a mixture with Fe2O30.8%)
3PO4/(MeO-10,000 Hczl (Tatal, Mb○
:CaO-4 or Mg0) molar ratio is 1.0-1.45
H3P0460 tyrinic acid solution or H3PO
475/acid solution, HO435% hydrochloric acid
The molar ratio of 3PO4 was adjusted to be in the range of 0.05 to 0.30, and the mixture was charged into a mixer with a rating of 1001. The mixer was called "Super Mixer" manufactured by Kawada Seisakusho Co., Ltd., and was equipped with stirring blades on the bottom of the mixing container and rotated at 5 (10 rpm). If necessary, the powders were thoroughly mixed [-5], then a fixed amount of a mixture of concentrated phosphoric acid solution and hydrochloric acid was added, and the stirring blades of the mixer were briefly rotated and stopped. Start the reaction. The contents undergo a vigorous decarboxylation reaction and foam. After a while, the foaming phenomenon subsides. At this stage, the stirring blade of the mixer is continuously rotated for several minutes to continue the reaction. The contents are The mixture gradually becomes viscous, increasing the load on the mixer. At this point, the rotation of the stirring blade is stopped, and the mixture is allowed to stand for a few minutes, and then allowed to ripen at room temperature for several hours to harden the reaction mixture. The aged reaction mixture By rotating the stirring blade of the mixer again, the mixture is crushed and granulated at the same time.
When the mixture became granular, the stirring blade was stopped and the contents were taken out from the mixer. After taking out, the contents were simply sieved to obtain a kneaded product without further drying. As can be seen from Table 1, when dolomite powder was subjected to a decomposition reaction using only a 75% concentrated phosphoric acid solution as in Example 1, the viscosity of the reaction product was high; It took a long time of 24 hours or more to ripen the grains7, and furthermore, the decomposition reaction continued gradually, making it difficult to commercialize the product. Therefore, this Example 1 is a reference example. On the other hand, add hydrochloric acid at a molar ratio of HC4/H3PO4 of 0j1
In the case of Example 2 and Example 3 in which 5 and 0.20 were added, the viscosity of the reaction product decreased, and the aging time was about 6 hours, and the crushing and granulation could be performed well. . Additionally, hydrochloric acid was added at a molar ratio of HCt/H3PO4 of 0.30. In the case of Example 4, the viscosity of the reaction product was extremely reduced, and granulation could not be performed as it was. Therefore, this Example 4 is a reference example. In Example 5, in which blast furnace water slag powder was added as a raw material to dolomite powder, the maturation time for crushing and granulation was about 1 to 2 minutes, but the viscosity of the reaction product was slightly high. It was difficult to obtain a product with a relatively fine grain size of 1 to 4 particles. Compared to Example 5, hydrochloric acid was used at a molar ratio of HCt/H3PO4 of 0.
．． In the case of Example 6, in which the reaction was carried out after addition of 300 ml, the entire process was carried out well and a product with a particle size of 1 to 41 M could be obtained. On the other hand, in the case of Example 7 in which a concentrated phosphoric acid solution with a concentration of 60% was used, the amount of water contained in the reaction system was excessive and a suitable granular product could not be obtained. When blast furnace water slag powder was mixed with dolomite powder at a ratio of 1:1, it was possible to crush and granulate the reaction product after aging for 5 to 6 minutes after the reaction. However, as in the case of Example 5, it is difficult to obtain a product obtained by crushing and granulating with a particle size of 1 to 4 mm, and it tends to be large particles. Therefore, Examples 7 and 8 This is a reference example. In Examples 9 and 10, the added hydrochloric acid worked effectively and it was possible to obtain products with a particle size of 1 to 4. . In Example 11, the amount of concentrated phosphoric acid solution was changed to H3Po4/(Me
A large amount of phosphoric acid (O1, HC7) was used in the molar ratio of 1.45 to increase the proportion of the phosphoric acid component in the product. In this example, as in Examples 2, 3, 9, and 10, all steps proceeded without any problems, and a product with a particle size of 1 to 4 mm was obtained without any drying process. It was done. The analytical values and granulation properties of these products one day after manufacture are shown in Table 2. In addition, when the existing phases in the product were identified by X-ray diffraction at the same time as the analysis, it was found that for all samples from Examples 1 to 1, ca(H2PO4)2・H2o1caHPo4,
Mg(H2”o,h”2HzOXMgHP04-3H2
I was able to get the 0(7) product to Q. C in products manufactured with mixed acid of phosphoric acid and hydrochloric acid! a
The diffraction peak of (H2PO4) 2.H2O becomes smaller as the amount of added hydrochloric acid [1] increases;
The diffraction peak of the unreacted dolomite became large, and at the same time the diffraction peak of unreacted dolomite became small. On the other hand, X-ray diffraction confirmed the formation of aluminum phosphates and iron phosphates such as AtPO4-3H20 and FePO4-3H20 in products manufactured using raw materials mixed with blast furnace Suijin slag powder (-5). In addition, in order to test the component stability of some products including the obtained product, temperature j 35 ° C 1 phase i J humidity 9
After being left in a constant temperature and humidity chamber of 0 mode for 30 days, each component was measured and the results shown in Table 3 were obtained. . In all products, unreacted residual dolomite (magnetic calcium carbonate) decreased slightly, and some progress of the reaction could be observed.
The changes in each component were extremely small and negligible. 4. Brief description of the drawings FIG. 1 is a process flow diagram of the method for producing phosphoric acid fertilizer of the present invention. Patent Applicant Murakashi Lime Industry Co., Ltd. Procedural Amendment May 1980 Dear Commissioner of the Patent Office (Examiner of the Patent Office) 1. Indication of the case Showa Leap Year Patent Application No. 158366 2. Name of the invention Phosphate Fertilizer manufacturing method 3, Relationship with the case of the person making the amendment Applicant name: Murakashi Lime Industry Co., Ltd. 4, Agent address: 1-1-5 Minami-Aoyama-chome, Minato-ku, Tokyo Date of amendment order (spontaneous) ) (Delivery date) Showa year Month Date Contents of Z amendment (1) Insert the following between lines 14 and 15 on page 2 of the specification. Note: The concentrated phosphoric acid solution used in the present invention is a concentrate of the so-called wet method phosphoric acid solution produced by decomposing phosphate ore with mineral acids, and contains phosphoric acid, water, and a small amount of phosphoric acid in the manufacturing process and raw material ore. A liquid containing impurities, or a solution of dry process phosphoric acid dissolved in water may also be used.''

Claims (2)

[Claims] (1) Add one or more mixtures of alkaline earth metal carbonates such as powdered calcium carbonate or magnesian calcium carbonate (dolomite) to a concentrated phosphoric acid solution with a concentration between ~80% and concentrated phosphoric acid solution. Adding concentrated hydrochloric acid at a ratio of 0.05 to 0.20 mol per 1 mol of concentrated phosphoric acid solution,
A method for producing a phosphoric acid fertilizer, characterized in that the reaction is carried out without further adding water. (2) A mixture of powdered calcium carbonate or a mixture of one or more alkaline earth metal carbonates such as magnesian calcium carbonate (dolomite) and blast furnace water slag powder has a concentration of (Capital) - Add concentrated phosphoric acid solution and concentrated hydrochloric acid at a ratio of 0.05 to 0.30 concentrated hydrochloric acid per 1 mole of concentrated phosphoric acid solution, without particularly adding water, A method for producing a phosphoric acid fertilizer, which comprises causing a reaction.