SU1101438A1 - Method for producing granulated slow-release oxamide-containing fertilizer - Google Patents

Abstract

A method for producing granular, slow-acting oxime containing aids, including sc19 oxime oxidation with a bitumen concentrate, followed by granulation of the resulting mass, characterized in that, in order to improve the physical and mechanical properties of the product, it is a reduction in cost reduction. in powder form in the amount of 0.5-5% by weight of the fertilizer, and Tsgao granules are pressed by pressing at forces of 1300-2500 kg. (L 4: eo j 6 p-w

Description

The invention relates to the production of mineral fertilizers and can be used to obtain granulated slow-acting nitrogen oxides based on oxides and oxides. There is a known method for producing slow granulated oxamide-containing fertilizer, in which powdered oxamide is mixed with anhydrous or hydrated calcium sulfate (gypsum) in a 1: 1 ratio of 1: 1 followed by granulation with granulated oxamide mixture with gypsum (2–4) and gypsum (10). as a finished fertilizer or after grinding is introduced into the complex fertilizer 1. The disadvantages of this method are a significant reduction in the nutrient content of the fertilizer (from 31.8 to 15.9%) due to the introduction of large quantities of gypsum, low mechanical strength of the fertilizer face (16.8 kg / cm), limited use of fertilizer (used only on acidic soils, for which the gypsum that is part of it is an improver). The closest to the invention is the method preparation of a slow-acting oxamide-containing fertilizer, in which the granulation of powdered oxamide is carried out by mixing oxamide with sulphite-bard concentrate solutions in the presence of water to obtain a pulp with a moisture content of 5040% (in ereschete on dry substance) forcing the mass through a die having a hole diameter (2-3) "m length and forming rods (2-3) - 10 m and a diameter of (2-3). 10 m of drying the obtained granules at a temperature of 363–403 K, followed by their fractionation. In this case, the concentration of the sulfite bard concentrate binder is 5-15 wt.% 2. The disadvantages of this method are the high concentration of the binder, which reduces the content of nutrients in the fertilizer, the short duration of the fertilizer, the increased hygroscopicity of the fertilizer due to high hygroscopicity of sulphite-bard concentrate, taken as a solution 2. The purpose of the invention is to improve the physical and mechanical properties of the product and (to reduce its decomposition. The goal is achieved According to the method for producing a granular, slow-acting oxamide-containing fertilizer, including blending oxamide with a binder sulphite-bard concentrate followed by granulation of the obtained Mass, sulphite-bard concentrate is used in powder form in an amount of 0.5-5% by weight of fertilizer, and granulation is carried out by bridging at forces of 1300–2500 kg. The mechanical strength of the :: ablets is determined by the method of their destruction in the axial direction (on the end surface). The drawing shows the dependence of the mechanical strength of oxamide granules on the pressing forces (the content of sulfite bard concentrate 0.5, 1 and 5% is indicated by curves 1, 2 and 3, respectively). The strength of granules is maximum (210-300 kg / cm) in the range of pressing forces equal to 1300-2500 kg. With a further increase in the pressing force, the strength decreases due to repressing caused by elastic stresses in the tablets when the structure is over-compacted. The obtained granules were used as a ready-made, slow-acting nitrogen fertilizer, the hygroscopic characteristics of which are given in Table. 2. Considered in the table. 1 and Examples 1-3, the degree of decomposition of oxamide in the soil, as well as under the conditions of the known method, was determined from the expression: The amount of nitrogen in the composition of inorganic compounds formed in the soil during decomposition (oxidation of oxamide. Decomposition degree,% of applied nitrogen in an organic farm. Example 1. A mixture of 0.050 kg of powdered oxamide and 0.00263 kg of sulphite-bard concentrate (sulphite-bard concentrate content 51), are thoroughly mixed and the mixture is tableted by pressing at a force of 1300 kg to obtain tablets dh. taking into account the rate of decomposition of the obtained oxamide granules in the soil with the granules obtained by the method 1 and using conditions known by the known method, composting was used at a temperature of 301 K and moisture content of 60% of the capillary soil moisture (black earth). , 1 kg. Fertilizer was applied in such an amount that the mass in the sample was 1, O Yu kg. The strength of the fertilizer granules is 290 kg / cm, its hygroscopic characteristics are given in table. 2. At 2 weeks intervals, the degree of decomposition of oxamide was determined. The repetition of the experience is fourfold. The results on the decomposition rate are given in Table. 1. Example 2. A mixture of 0.050 kg of powdered oxamide and 0.00025 kg of sulphite-bard concentrate (content, Tie-bard sulphite concentrate in the fertilizer is 0.5%) is tabletted by pressing at a force of 2000 kg to obtain tablets d, h 5ЧО m and a strength of 225 kg / cm. The determination of the rate of fertilizer decomposition in soil was carried out according to the method of Example 1. The data on the degree of decomposition of fertilizer in soil and the characteristics of its hygroscopicity are given in Table. 1 and 2.10

.. Example 3. A mixture of 0.050 kg of powdered oxamide and 0.0005 kg of sulphite bard concentrate (sulphite bard concentrate content in fertilizer) is tabletted 5 by pressing to obtain granules d 5-10 m, h 5-10 m at effort 2500 kg. Granules with a strength of 235 kg / cm are obtained. Data on the degree of decomposition of fertilizer and characteristics of its hygroscopicity are given in Table. 1 and 2.

The data table. 1 and 2 indicate that the addition of sulfite-bard concentrate to oxamide in the amount of 0.5-5.0 wt.% In the process of its granule

Double-sided pressing contributes to an increase in the tip of the duration of the crush for two weeks and an increase in the strength of the granules by 3.4-4.8 times. This improves the physical properties of the fertilizer, in particular, its hygroscopicity decreases. In addition, the degree of decomposition of granular fertilizer containing less than 0.5% sulphite-bard concentrate is commensurate with the degree of decomposition of pure oxamide.

The introduction of sulphite-bard concentrate into the oxamide in an amount exceeding 5 wt.% Is inexpedient, since it leads to a decrease in the nitrogen content in the fertilizer. Granulated oxamide, obtained by the proposed method, is especially effective in irrigated agriculture, for example, when rice is grown on flooding, where pacTBOpHNiHe nitrogen fertilizers (urea, ammonium sulfate) have been found to be ineffective due to significant nitrogen losses due to dinitrification and washing out by filtration waters.

Hygroscopic characteristics of oxamide-based nitrogenous fertilizers with carrier gas humidity -f - 81%

table 2

+ 15% SBC

N

+ 5% SBC + 1% SBC + 0.5% SBC

75.0

2.23 76.7

1.1 77.0

0.56 77.0

0.35

Claims (1)

METHOD FOR PRODUCING GRANULATED SLOW-ACTING OXAMIDE CONTAINING FERTILIZER, comprising mixing oxamide with a sulphate-binder concentrate followed by granulation of the resulting mass, characterized in that, in order to improve the physicomechanical properties of the product and reduce the concentration of sulfate, it is used form in an amount of 0.5-5% by weight of the fertilizer, and granulation is carried out by pressing with efforts of 1300-2500 kg. SU. „1101438