SU833923A1 - Method of producing high-concentrated phosphorus fertilizer - Google Patents

Description

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This invention relates to a method for producing phosphate fertilizers that can be used in agriculture. as a highly concentrated fertilizer with a post-effect effect.

A known method of producing highly concentrated phosphate fertilizer by heating condensed calcium phosphate in an atmosphere of saturated water vapor at 180-200C and a suspended form of phosphoric acid.

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The disadvantage of this method is the need to introduce phosphoric acid to regulate the solubility of the resulting product.

The closest to the proposed technical performance and the achieved result is a method of obtaining highly concentrated phosphate fertilizer by treating pre-ground condensed phosphate with calcium vapors for 1 h 2.

The disadvantage of this method is that all the phosphorus in the fertilizer is represented by water-soluble compounds, and therefore, when applied to the soil of this fertilizer

nutrient loss due to leaching, which reduces fertilizer utilization. The duration of the aftereffect is determined. only the rate of hydrolysis of calcium pyrophosphate in the soil. In addition, with. granulation cannot achieve an even distribution of water- and citrate-soluble forms of DO in the granules.

The purpose of the invention is to create the possibility of the formation of both water-soluble forms and citrate-soluble as well as more uniform recoil.

5 nutrients to the soil.

The goal is achieved by the fact that in the method of obtaining highly concentrated phosphorus fertilizer, which includes the treatment of condensed phosphate with calcium with water vapor at elevated temperature, the granulated condensed calcium phosphate with a diameter of 0.25-3.0 mm is treated with water vapor.

5 for 15-60 minutes

Claims (2)

Under the action of water vapor, when heated, calcium phosphate is subjected to hydrolytic cleavage, as a result of which the initial citrate-thorny granule is coated with a water-soluble layer, represented by ortho-pyrophosphates. When such a granule is introduced into the soil, the water-soluble layer provides both a direct action due to the orthophosphate anion, and some aftereffect due to the pyrophosphate anion hydrolyzed in the soil by the reaction H ,, P, H, 0-2H2P04 Leaving the granulated condensed phosphate in the soil degrades from the surface with the formation of ortho and high molecules of the anions, the ratio between which is determined by the ratio SaogP O in the initial phosphate. The high molecular weight phosphates are then hydrolyzed from a series of intermediate stages to the orthophosphate form, thereby providing a long lasting effect for plants of phosphorus fertilizer. The effect of the fertilizer is maintained throughout the entire period, as the orthophosphate is applied initially and is formed continuously during the degradation of the ultraphosphate. Example. Granulated calcium ultraphosphate (75.2%, Ca 24.3%) with a particle diameter of 0.25 mm is treated with water vapor for 1 hour in a fluidized bed furnace. The content in the resulting product,%: total 65.0; water soluble forms 44.9) citrate soluble forms 20.1. By varying the duration of the pyrolysis process and the size of the granules, products with different ratios of water and citrate soluble forms are obtained. In tab. 1 shows the content of water- and citrate-soluble forms in the products, depending on the size of the initial phosphate granules. Table. . Continuation of the table. 1 In table. Table 2 shows the content of odor- and citrate-soluble forms in products depending on the treatment. (Diameter of granules 0, 5 mm), Table2. 71.6 -4.9, 70.1 19.9 The proposed method allows to obtain fertilizers with a gradual transfer of nutrients to the soil, reduce their loss and thereby increase the efficiency of the fertilizer. The invention method of obtaining highly concentrated phosphate fertilizer, including the treatment of condensed phosphate with calcium water vapor at elevated temperature, characterized in that, in order to create the possibility of formation of both water-soluble forms and citrate-soluble, as well as a more even return of nutrients to the soil, water, inhale nutrients, as well as more uniform return of nutrients to the soil, water, and citrate-soluble, as well as a more even return of nutrients to the soil, water. process granulated condensed calcium phosphate with a diameter of 0.25-3.0 mm for 15-60 minutes. Sources of information taken into account in the examination 1. The author's certificate of the USSR 479745, cl. On 05/13/06, 03/12/73. 2. USSR author's certificate number 484207, cl. C 05 B 1/04, 29jl0.71.