SU1255614A1 - Method of producing slowly-soluble granulated potassium fertilizer - Google Patents

Description

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The invention relates to the technology of obtaining mineral fertilizers from sylvinite ores and can be used in enterprises processing potash ores with a high content of clay and water-insoluble impurities.

The aim of the invention is to reduce the solubility, increase the mechanical strength and improve the agrochemical properties of the fertilizer.

Example 1, The original ore is crushed and desliming, thickened clay-salt sludge is treated with a modifying additive.

100 kg of clay-salt slurry is treated with acidic tar in an amount of 10 kg (10% of the mass of clay-salt slurry), then swept with pulverized potassium chloride in an amount of 180 kg to obtain 40% potassium salt. After mixing, the mixture is pressed, the obtained granules are dried at: 120-160 ° C and the finished fraction of 4-1 mm is recovered, which is used as a ready fertilizer. I

Example 2. 100 kg of clay-salt sludge is treated with acidic tar in an amount of 15 kg (15% of the mass of clay-salt sludge), then mixed with pulverized potassium chloride in an amount of 175 kg to obtain 40% potassium salt. The process is then carried out as in Example 1.

Example 3. 100 kg of clay-salt slurry is treated with acidic tar in an amount of 17 kg (17% of the mass of clay-salt slurry), then mixed with pulverized potassium chloride in an amount of 173 kg to obtain 40% potassium salt. Next, the process is carried out as in Example 1.

Acid tar is used in the amount of 10-17% by weight of clay-salt sludge. Further increase in acid sludge consumption is impractical due to He3Ha4HTejn3Horo improving the physicochemical properties of the finished product, reducing consumption of less than 10% does not have a noticeable effect on improving the properties of the finished fertilizer and is not sufficient for exchange reactions between the carbonates of clay-salt sludge and sulfuric acid acidic tar. Acidic tar is a significant waste of sulfuric acid cleaning.

five

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raw fractions and raw paraffin in the production of protein-vitamin concentrates and sulphate additives and has the following chemical composition, May. %: sulfuric acid 79.1; water 7.4; organic matter 13.5. Group composition of organic matter, May. %: oil-resinous substances 72.1; resinous asphalt 1.2; esters of 0.7; carboxylic acid 2.2; sulfonic acid 23.8.

In tab. 1 presents experimental data on the effect of addition on the quality of the product (solubility and strength of the granules) obtained by the known and proposed

ways. I

Samples of fertilizers are pressed at a pressure of 84 MPa for 3 minutes and dried at 140 ° C. The solubility is determined by the gravimetric method by dissolving fertilizer granules weighing 5 g in 100 ml of water for 30 minutes. The strength of the specimens is determined by the method of destruction under axial compression. Comparative analysis are given in table. 1 data demonstrates the advantages of the proposed

 way compared to the known. The strength of the potassium fertilizer obtained by the proposed method is 1.5 times higher, and the solubility is 1.7–2 times lower compared to the known method. This is due to the fact that the organic mass of acidic tar contains unsaturated hydrocarbons, which have a high ability to undergo polymerization and polycondensation reactions and form high molecular weight compounds during the drying process, which bind the fertilizer particles with a spatial polymer mesh. As a result, the strength of the granules increases, they are not destroyed during storage and transportation, they do not form dust-like fractions. The polymeric film formed prevents the penetration of moisture into the potash fertilizer granules, thereby reducing its dissolution rate. In addition, a decrease in solubility is also associated with a significant hydrophobic effect of hydrocarbons that are part of the organic mass of acid tar. Water repellency reduces hygroscopicity and

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caking of the finished product by reducing the absorption of moisture from the air. Reducing caking reduces labor costs for transportation and fertilization to the soil, and reduces their losses.

Table 2 presents comparative data on the content of the water-soluble part in the sludges treated by the known and proposed methods.

As can be seen from the above data, the proposed method is not inferior, and even slightly exceeds the known method in the efficiency of transferring macro- and microelements from a water-soluble form to a water-soluble one.

The implementation of the proposed method allows to obtain fertilizer with

Sol Na Acid

Solubility,%

58.09 49.62 51.82 44.57 43.20

30% Strength, solution MPa (known)

41

Sour tar (offered

)

Solubility,%

Strength,

that

40.84 29.53 22.85 21.64 24, i2

5159616462

table 2

0.08208.58 42.9

0.12010.1 50.5

0.052012.8 64.0

44

improved agrochemical properties. Studies on the comparative effectiveness of new forms of potash fertilizers prepared on the basis of clay-salt sludge treated with acidic tar for crops of barley and alfalfa were carried out under conditions of vegetative experiments on sod-podzolic sandy loam soil. As shown by tests, potash fertilizers prepared on the basis of clay-salt sludge treated with acidic tar are promising fertilizers. The yield increase under the conditions of the vegetative experiments compared with the background (NPK), depending on the content of the modifying additive in them, acidic tar, consists of barley grains 16-20%, alfalfa hay 20-23%.

Table D

40

43

46

47

8.82 44.1 10.64 53.2 13.28 66.4

 ,

The amount of sludge

g

The amount of water-soluble part in the slimes by the way

the famous

proposed

0.17 20 12.9 64.5 13.38 66.9 0.20 20 13.1 65.1 13.34 66.7

stny

I

proposed

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Claims (1)

METHOD FOR PRODUCING SLOWLY SOLUBLE GRANULATED POTASSIUM FOOT FERTILIZER by grinding and desliming the ore, thickening the clay-salt sludge, then treating it with a modifying additive, displacing it with a dusty fraction of potassium chloride, granulating, drying, isolating the finished fraction, characterized in that, in order to reduce solubility, increase mechanical strength and improve the agrochemical properties of the fertilizer, acid tar is used as a modified additive ί waste of sulfuric acid purification of oil fractions and raw paraffin in the production of protein-vitamin co centrate sulphate and additives in an amount of 10-17% by weight slurry of clay and salt.