CS272952B1 - Method of solid phosphoric fertilizer production - Google Patents

Abstract

The invention concerns a method of producing solid phosphoric fertiliser in which the share of phosphoric oxide from the extractive trihydrogen phosphoric acid and ground phosphorus is here between 0.8 : 1 to 1.8 : 1. The method is based on effective homogenisation of the reaction compounds, whereas, depending of the given ratio, sulphuric acid and/or ammonium sulphate and/or water is added to the homogenisation stage of the process so that the total amount of the reaction mixture represents the immitted amount of water of 8.8 to 32.0 % and immitted amount of sulphur ions represents 0.46 to 9.38 %. Derivatives of lignosulphonic acid can also be added to the homogenisation stage. The stiffened reaction mixture is broken up by mechanical force.

Description

The invention relates to a process for the production of a solid phosphorous fertilizer in which the proportion of PgOg from the extractive trihydrogenphosphoric acid and the phosphite is in the range of 0.6: 1 to

2,3: 1.

In the context of the worldwide increase in raw material and energy prices, the ways of ensuring their economic entry into crop production are in the field of phosphorus fertilizer production. It is known that about 10-20% of the applied water-soluble phosphate fertilizers are used in the first year (I. Michalík, “Phosphorus intake and metabolism in plants”, Agriculture 2/85, A series, VEDA - publishing house SAS, Bratislava 1985;

EC Sample et al., "Reaction of Phosphate Fertilizers in Soils, Chapter 11 in" The Role of Phosphorus in Agriculture Madison, WI 53711, USA 1980). For this reason, fertilizers in which the traditionally recognized form of P ₂ 0g was water-soluble are starting to be increasingly applied to sources of P ₂ 0g in a gradually effective form (VI. Lavers,

The British Sulfur Corporation Ltd., Factors Affecting the World Fertilizer Industry to 2000 and Bey Blond, Trends and Developments Seminar in Fertilizer Industry, Istanbul (Turkey), 13-17 May 1985).

The main source of the P ₂ 0g post-sorber is the use of Fertilizer manual powdered, finely ground phosphites. 13, UNIDO, New York, 1980; "Ground rock phosphate for direct application", Annual Fertlizer Rewiew 1974, Roma), modified by granulation (P. P. Thíiring, paper presented at the 6th AGRICHEM Congress "Chemistry in Agriculture, Bratislava - June 1984) incorporated into granular fertilizers ( AO No. 254 029, AO No. 254 028, USSR No. 1 217 859, USSR No. 971 833) or partially decomposed by mineral acids (Garbachev I., Soil Science Society of America, 1981, 45, 5, Novikov AA; Zavertiaeva TI, "Technologia digifrofosa - novovo vida phosphorus udobrenij", Seminar after trends and changes in the process of udobrenij, Stambul (Turcia), 13-17 May 1985; Kostadinov N., Popov P., Garbučev I., "The Phosphorous Pollution of Humiliated Growth in the Constitution of the Doors and the Door-Oliver Method", Seminar on Trends and Changes in Udobrenij, Stambul (Turcia), May 1985.

In addition to reducing the raw material intensities of phosphorus entry into agricultural practice in the form of new types of fertilizers, the industry is roosting the technological possibilities of their production on existing machinery and technology, as far as possible with minimal modifications.

It has now been found that the new type of phosphorous fertilizers (partially decomposed phosphites) containing simultaneously phosphorus bound in the form of dicalcium phosphate, dicalcium phosphate and dicalcium phosphate, in which the proportion of phosphorus pentoxide originating from extracting to 2.3: 1, can be prepared by a method based on the efficient homogenization of ground phosphorus with commercially available trihydrogenphosphoric acid, the temperature of which can be between 15 and 85 ° C and the phosphorus pentoxide content of 47 and 55 wt. %. Depending on the ratio P ₂ 0g of the extractive trihydrogenphosphoric acid and phosphorus, sulfuric acid and / or ammonium sulphate and / or water are added to the homogenization stage of the process. The amount of water introduced by all reactants is 8.8 to 32.0% by weight. and the total content of the introduced sulphate ions is 0.46 to 9.38%.

Optionally, lignosulfonic acid derivatives are added to the homogenization stage of the process. After solidification, the reaction mixture disintegrates under the influence of mechanical force.

The resulting product can be used in powder form for direct application or used as an intermediate in the production of granular fertilizers. Compared with known production methods, the new process allows the production of phosphorous products in a wide range of P ₂ Og ratios from extraction HgPO 4 and phosphorus with a total P 2 O 8 content in the range of about 32 to 42%. The proportion of P 2 O 8 in the water-soluble form is in the range of about 35 to 70%. A further advantage is the possibility of realizing this process on an existing machine-technology apparatus of the ventricular triple superphosphate production process. The method makes it possible to ensure the economical entry of phosphate fertilizers into agricultural practice.

CS 272 952 Bl

The following examples illustrate but do not limit the scope of the invention.

Example 1

A homogenized mixture containing 237 g of extraction HgPO ₄ containing 51.83% P ₂ O ₅ at 65 ° C and 6.2 g of ammonium sulfate as a 38% solution was introduced into a laboratory mixer. 150 g of Oordan phosphite with a particle size of 92.4% of particles smaller than 0.25 mm and a P ₂ 0g ³ content of 21.96% were added to the mixer. Within 5 s, the system was homogenized at 6000 rpm and the reaction mixture was poured into 0.75 L stainless steel aging flasks. After this time, the solidified product was mechanically removed from the aging vessels and subjected to chemical analysis. A product of the following composition was obtained:

total content P ₂ 0 ₅ = 42,4% content Ρ £ θ5 ^a ^ ° ^v0 ^ ^{n H} 3 ^P0 4 = 5/94% content P ₂ 0 ₅ water-soluble = 35,19% content ll ₂ 0 = 9,14 %

Example 2

The following raw materials were continuously fed into the laboratory high-speed flow mixer:

- 25 g / s ground phosphorus with a particle size of 92,4% of particles smaller than 0,25 mm containing 31,96% P ₂ 0 ₅ , 50,36% CaO and 1,14% H ₂ O,

- 20 g / s of 60 ° C trihydrophosphoric acid containing 51,82% / 25%

MgO, 2.3% R ₂ 0 ₃ and 1.48% SoJ

The extraction was homogenized orthophosphoric acid, sulfuric acid, and water in an amount of 7.5 h H ₂ S0 ₄ and 12.5 g of H ₂ 0 per 100 g HgP0 _fourth The reaction mixture was collected in 0.75 L stainless steel vessels. The vessels were placed in a water bath where they were heated at 75 ° C for 30 minutes. After this time, the solidified product was mechanically removed from the aging vessels. The product of the following composition was obtained as follows:

P ₂ 0 ₅ - free P ₂ 0 ₅ - water dist. = 2,48% * 20,61% ^P 2 ° 5 “ ^c i ^ ^roroz = 22,17% P ₂ 0, - total = 37.67% h ₂ o - = 11.40%

Example 3

All other experiments were carried out in a manner identical to Example 1. Their decisive characteristics are shown in the following table.

CS 272 952 Bl

P. no. Proportion of PgOg in H ₃ PO ₄ and phosphorus product Temperature H ₃ P0 ₄ ° C) Dosing H ₂ S0 ₄ (100%) per 100 parts h ₃ by ₄ (parts) Dosing (nh ₄ ) ₂ with ₄ per 100 parts h ₃ by ₄ (parts) Dosage H ₂ 0 per 100 parts ^H 3 ^PO 4 (parts) Content P ₂ ° g total in product (%) ^P 2 ° 5 water-soluble in the product from total ^P 2 ° 5% First 0.6! 1 64 7.5 15 35.5 34.2 41.7 Second 0,8: 1 55 - - 20 37.2 42.8 Third 0,8: 1 85 20 17.5 20 34.6 53.8 4th 0,8: 1 20 20 - - 37.5 48.8 5th 0.98; 1 60 10.5 - - 39.3 51.4 G. 1,08: 1 35 - 7.5 9.8 39.6 50.7 7th 1,19: 1 65 - - 31.8 37.5 51.7 8th 1,30 _: 1 - 12.5 - - 40.8 58.4 9th 1.46: 1 70 - - 22.5 39.6 54.3 10th 1,63: 1 85 - 8.5 15.0 38.1 64.3 11th 1.80: 1 65 - - 18.2 41.3 60.4 12th 2,30: 1 55 • 4.5 5.5 42.1 78.8

OBJECT OF THE INVENTION

Claims (1)

OBJECT OF THE INVENTION Process for producing a solid phosphorous fertilizer in which the proportion of phosphorus pentoxide from the extractive trihydrogenphosphoric acid and the ground phosphorus is in the range of 0.6: 1 to 2.3: 1, characterized in that the phosphite is effectively homogenized with a commercial extractive trihydrogenphosphoric acid at 15 % to 85 ° C, containing 47 to 55 wt. % sulfuric acid and / or ammonium sulphate and / or water in the amount of 8.8 to 32.0 wt. and the total content of sulphate ions introduced into the process is 0.46 to 9.38%.