SK288976B6 - Process for the production of granular ammonium nitrate with dolomite containing the nitrification inhibitor 4-amino-1,2,4-triazole - Google Patents

Abstract

Described is a process for the production of granular ammonium nitrate with dolomite containing a nitrification inhibitor of 4-amino-1,2,4-triazole by incorporating it inside the granules in order to stabilize the ammonium nitrogen in the fertilizer (17). The fertilizer is prepared by adding 4-amino-1,2,4-triazole (6) to the reaction solution of ammonium nitrate (2) with dolomite (3) in the reactor (1), and then this reaction solution with the addition of 4 -amino-1,2,4-triazole (8) is processed by granulation (9). Ammonium sulphate (4) can also be added to the reaction solution (5) to improve the physico-mechanical properties of the fertilizer (17).

Description

The field of technology

The invention belongs to the field of agrochemistry, specifically, it relates to the method of production of granular ammonium slag with dolomite (hereinafter LAD) containing the nitrification inhibitor 4-amino-1,2,4-triazole, used as a granular fertilizer.

Current state of the art

The aim of adding nitrification inhibitors (IN) to fertilizers is to inhibit the biological oxidation of ammonia nitrogen to nitrate nitrogen, i.e. to slow down the bacterial oxidation of ammonium ions (NH ₄ ⁺ ) in the soil by Nitrosomonas type bacteria by reducing their activity for a certain time (several weeks). These types of bacteria convert the ammonium ion into nitrite, which is then subsequently converted into nitrate ion by other bacteria Nitrobacter and Nitrosolubus. Essentially, the use of IN reduces the loss of nitrate ion, which is easily leached from the soil, or further reduces the loss of nitrogen, which is released to the atmosphere by the formation of nitrogen oxides by denitrification.

Inhibitors of nitrification in fertilizers, in addition to reducing losses of nitrogen through leaching and the escape of N gases into the air, make it possible to reduce the number of fertilizer applications, which leads to savings in human labor and other costs. The advantages of using nitrification inhibitors in fertilizers containing ammonium or amide nitrogen are widely known and are reported in many publications, for example Trenkel (2010). This work lists the most well-known nitrification inhibitors, used in different forms and applied to fertilizers by different technological procedures. However, in the case of fertilizer production technologies that contain nitrification inhibitors, there is a fundamental requirement that the inhibitory effect of the inhibitors is maintained after the fertilizer production process during their handling until their application to the soil.

According to Trenkel, one of the most effective nitrification inhibitors is 4-amino-1,2,4-triazole (AT or ATC).

The effect of 4-amino-1,2,4-triazole as a nitrification inhibitor on the stabilization of mineral ammonium nitrogen has been known for many years. Bundy & Bremner (1973) and Bundy (1973) measured and compared the effect of ATC with several nitrification inhibitors. In the soils and conditions used, the average effectiveness of the strongest inhibitors was in the order: 2-chloro-6-(trichloromethyl)pyridine (nitrapyrin) > ATC > sodium azide > potassium azide > 2,4-diamino-6-trichloromethyl-s-triazine > dicyandiamide etc.

A comparison of nitrapyrin and ATC in soils with different textures was discussed by Guthrie and Bomke (1980). Although numerous laboratory studies have demonstrated the effectiveness of certain nitrification inhibitors, many field studies have shown no significant crop response to inhibitor treatment. However, most of the field studies to date have only evaluated nitrapyrin, which cannot be conveniently applied to solid fertilizers due to its volatility. ATC is a non-volatile, water-soluble nitrification inhibitor that can be easily applied to solid fertilizers without loss of volatility.

Ali et al (2012) studied the effect of eight compounds on the nitrification of applied ammonium sulfate in two soils incubated at high (35 °C) and medium (16 °C) temperatures. The tested compounds were: 1H-benzotriazole, ATC, benzothiazole, 3-methylpyrazole-1-carboxamide, 4-bromo-3-methylpyrazole (BMP), pyrazole and lignosulfonic acid of two different molecular weights. At both temperatures tested, ATC was the most effective compound with 44-71% inhibition at 35°C and 84-90% inhibition at 16°C, both at 10 mg/kg and followed for four weeks.

A more recent study (Mahmood et al. 2017) aimed to compare the potential of ATC with two of the most widely used nitrification inhibitors, 3,4-dimethylpyrazole phosphate (DMPP) and dicyandiamide (DCD), to inhibit ammonium sulfate nitrification in an alkaline calcareous soil incubated in aerobic conditions at temperatures of 35 °C, or 25 °C. Inhibitors were loaded into ammonium sulfate granules and inhibition of nitrification was calculated based on the loss of ammonium nitrogen and the accumulation of nitrate nitrogen. At 35°C, the inhibitory effect of DCD and DMPP persisted for only one week, while ATC was effective for up to 4 weeks. At 25 °C, the inhibitory effect of these substances was comparable.

Both studies indicated that ATC could be a potential nitrification inhibitor for agricultural use, especially in warm and temperate climates.

ATC was first used as an IN in US patent 3,697,244 in 1968 for nitrogen fertilizers containing ammonium ions, where in claim 1 the protected compounds ATC, 3,4-diamino-4H-1,2,4-triazole or their addition salts with mineral acid. Application of inhibitors is in the form of a liquid concentrate.

Almost at the same time, the Japanese patent JP 7104135 A was applied for. The subject of the patent protection is a method of suppressing the nitrification of ammonium nitrogen in the soil, thereby preventing the rapid loss of nitrogen from the soil. It is based on treating the soil with at least one 1,2,4-triazole or 4-amino-1,2,4-triazole, or their adducts with acid, in an amount sufficient to suppress nitrification. It can be used together with a carrier or fertilizer. The carrier can be water, xylol, benzene, alcohol, acetone, talc, gypsum, vermiculite, bentonite, soil or diatomaceous earth. The fertilizer can be ammonia, ammonium sulfate, chloride, nitrate, carbonate or phosphate, urea; or beans, fish waste or compost.

The subject of patent WO 2011137393 A1 (2010) is a fertilizer that includes a source of nitrogen such as urea, ammonia, ammonium nitrate or combinations thereof and a reaction product of formaldehyde (UFP), a source of ammonia and a nitrification inhibitor. A nitrification inhibitor can be ATC, its derivatives and any combination thereof.

The subject of another patent WO 2016070184 A1 (2014) is an improved nitrification inhibitor composition that contains UFP particles and a nitrification inhibitor that can be ATC for use as an additive in liquid and solid fertilizers, typically containing urea.

Mikhaylov et al. (1985) published work on the production and use of urea enriched with ATC.

Reducing the application amount of nitrification inhibitors is possible by using a combination of two or more inhibitors, as long as they are compatible with the fertilizers in which they are added. Such a combination of inhibitors can, through the mutual synergistic effect of their inhibitory effects, lead to a reduction in the total application quantity of inhibitors, to a more efficient use of nitrogenous fertilizers and to a gentler burden on the environment.

The invention SU 1137096 A1 (1983) relates to inhibitors of nitrification of ammonium nitrogen in the soil and can be used in agriculture. According to him, the IN mixture is prepared by mixing ATC and DCD in a ratio of 25-95% ATC and 5-75% DCD. The soil is moistened to 60%, allowed to stand in a thermostat at 28°C for 14 days, and then the content of ammonium ions and nitrate nitrogen and the rate of nitrification are determined. Analysis of the results showed that the simultaneous use of ATC and DCD reduces the nitrification rate by 1.5 times in black soil and 5 times in gray soil compared to the uninhibited procedure.

Joint use with ATC and thiourea in urea granules is the subject of patent protection DD 227957 Al (1984).

In Chinese patent application CN 1712387 A (2004), a long-acting composite fertilizer is described, consisting of nitrogen, phosphorus, potassium and a mixture of DCD and TZ in the amount of 0.4-1.2% by weight, where DCD constitutes 0-8% share and ATC 1 - 3% share, that means that the fertilizer can also contain ATC itself as IN. This composite fertilizer can achieve a high utilization of nitrogen and a long life of the fertilizer.

Patent application CN 107176894 A (2016) deals with NPK fertilizer with the addition of nitrification inhibitors DCD and ATC in the same proportions as in the previous patent application.

In patent CN 101298399 B (2007), an aqueous composition containing a synergistic agent is protected, where, in addition to ATC and DCD, there is also N-(n-butyl)-phosphorytriamidothioate (NBPT), dehydrated sorbitan fatty glyceride and water.

In none of the mentioned patents, the nitrification inhibitor 4-amino-1,2,4-triazole is not introduced into the hot liquid reaction solution (melt) of the ammonium dolomite fertilizer (LAD) before its granulation.

LAD is a granulated single-component nitrogen fertilizer, prepared from ammonium nitrate, finely ground dolomite and possibly also ground ammonium sulfate. It contains 27% by weight of total nitrogen, with the same ratio of nitrate nitrogen and ammoniacal nitrogen, and smaller amounts of calcium, magnesium and possibly sulfur.

The problem of introducing organic substances into single-component fertilizers of the ammonium nitrate type with a high nitrogen content is the explosive properties of ammonium nitrate, which can significantly affect the presence of organic substances in the fertilizer. This is dealt with legislatively in Annex III of EC Regulation No. 2003/2003: Technical regulations for fertilizers based on ammonium nitrate with a high nitrogen content; point 1. Properties and limits of single-component fertilizers based on ammonium nitrate with a high nitrogen content; point 1.2 Flammable components.

However, in the case of LAD fertilizer with the addition of the nitrification inhibitor ATC, the limited mass percentages of combustible substances designated as carbon are not indicated when the nitrogen content is below 28% by weight. In addition, experiments have shown that ATC is very stable in fertilizers of this type even at higher melt production temperatures, and chemical changes of this substance do not occur.

The essence of the invention

The subject of the invention is a method of producing granulated ammonium slag with dolomite with the addition of the nitrification inhibitor 4-amino-1,2,4-triazole (ATC) to the hot reaction solution (melt) of the fertilizer before its granulation based on the following method:

Nitrification inhibitor ATC in an amount from 0.4% by weight to 4% by weight of the ammoniacal nitrogen content expected in the final fertilizer is added to the hot reaction solution of the LAD fertilizer at a temperature of 110 to 170°C in a mixing reactor. After being incorporated into the reaction solution, the ATC is allowed to stir for 5 to 90 minutes.

The resulting reaction mixture is subsequently granulated, dried and surface-treated into the resulting fertilizer.

Advantageously, ammonium sulfate can be added to ammonium nitrate in an amount of 0.1 to 0.5% by weight. to improve the physical properties of granular fertilizer.

Incorporation of the ATC inhibitor mixture according to the mentioned procedure into the skeleton of the fertilizer granules leads to the preservation of the properties of the inhibitor not only during production and handling, but also during the storage of the fertilizer and manifests itself as an inhibitory effect on the stabilization of ammonium nitrogen in the soil after the application of granular fertilizer.

A significant advantage of incorporating the ATC inhibitor inside the granules compared to applying it to the surface of the granules is the uniform content of the inhibitor in the entire volume of the granulated fertilizer.

In addition, the presented method of production of granular fertilizer enables the preservation of good physical-mechanical properties and nutritional values of this fertilizer.

Overview of images on drawings

The invention is explained in more detail with the help of the drawing, in fig. 1 is a schematic representation of the production method of granulated LAD containing the nitrification inhibitor 4-amino-1,2,4-triazole.

Examples of implementation of the invention

A concrete example of the implementation of the method for the production of granular ammonium slag with dolomite containing the nitrification inhibitor 4-amino-1,2,4-triazole according to the invention is presented as an illustration and not as a limitation of the invention, not all components and means are dealt with in detail. Those skilled in the art will probably be able to discover, using no more than ordinary experimentation, other equivalents to a specific embodiment of the invention, and such equivalents will also fall within the scope of the described patent claims.

To reactor 1 no. 1, 28.43 t/h of 97% ammonium nitrate 2, part of dolomite 3 in the amount of 5.12 t/h and 175 kg/h of ground ammonium sulfate 4 are dosed. Into reactor 1 no. 2, 52.5 kg/h of 4-amino-1,2,4-triazole (ATC) 6 is added to reaction solution 5. The temperature of reaction solutions 5 and 8 in reactor 1 no. 1 and no. 2 is maintained in the range of 145-155 °C by the heat of reaction solutions 5 and 8 alone or by additional heating of 7 with steam. The reaction solution with ATC 8 passes through a hydraulic overflow into reactor 1 no. 3. Retention time of the mixture in reactor 1 no. 2 and no. 3 is about 50 min. From reactor 1 no. 3, the reaction solution with ATC 8 flows into granulation 9, where granulation of this solution takes place together with the second part of dolomite 3 in the amount of 2.76 t/h and recyclate 10. Wet granulate 11 is moved to drying 12, after drying further to sorting 13, after cooling 14, the surface is treated 15 with a substance against dustiness and caking 16. In this embodiment, 35 t/h of fertilizer 17 with a composition of 26.87% by weight is produced. of total nitrogen, of which 13.49 wt.% of ammonium nitrogen, 4.69 wt.% magnesium, 0.135% wt. 4-amino-1,2,4-triazole and 0.17 wt.% water.

List of relationship tags

1 2 Reactor Ammonium nitrate 5 3 Dolomites 4 Ammonium sulfate 5 Reaction solution 6 4-amino-1,2,4-triazole 7 Heating 10 8 Reaction solution with 4-amino-1,2,4-triazole 9 Granulation 10 Recycled 11 Wet granulate 12 Drying 15 13 Sorting 14 Cooling 15 Surface treatment 16 Substance against dust and caking

Fertilizer

Literature

Bundy LG, Bremner JM, 1973. Inhibition of Nitrification in Soils, Soil Sci. Soc. Amer. Proc., 37: 396 - 398.

Bundy LG, 1973. Control of nitrogen transformations in soils, Dissertation, lowa State University, Retrospective Theses and Dissertations. 5072.

https://lib.dr.iastate.edu/rtd/5072

Guthrie TF, Bomke AA, 1980. Nitrification Inhibition by N-Serve and ATC in Soils of Varying Texture, Soil Sci. Soc. Am. J., Vol. 44:314-332.

Mikhaylov Yul, Vodopyanov VG, lánov MG, Mushkin Yul, Búrmistrov VN, Blyum BG, Vyvolokina AG, Yashin NN, Strahkova lYa, Mezhunova NP, 1985. Preparation of carbamide supplemented with nitrification inhibitor 4-amino-1,2,4-triazole , Khimicheskaya promyshlennost in Russian, 9: 540-543.

Rehmat AA, Kanwal H, Iqbal Z, Yaqub M, Khan JA, Mahmood T, 2012. Evaluation of some nitrification inhibitors at different temperatures under laboratory conditions. Soil Environ, 31 (2): 134-145.

https://www.researchgate.net/publication/262313404_Evaluation_of_some_nitrification_inhibito rs_at_different_temperatures_under_laboratory_conditions

Mahmood T, Rehmat AA, Lodhi AA, Sajid MA, 2017. 4-Amino-1,2,4-triazole can be more effective than commercial nitrification inhibitors at high soil temperatures, Soil Research 55: 715722.

https://www.researchgate.net/publication/315782966_4-Amino-124- triazolecanbemoreeffectivethan _commercial_nitrification_inhibitors_at_high_soil_temper atures Trenkel M, 2010. Slow - and Controlled-Release and Stabilized Fertilizers An Option for Enhancing Nutrient Efficiency in Agriculture, Second edition, International Fertilizer Industry Association (IFA) Paris, France, ISBN 978-2-9523139-7-1.

Claims (5)

1. Method for the production of granular ammonium nitrate with dolomite containing the nitrification inhibitor 4-amino-1,2,4-triazole, characterized in that to ammonium nitrate (2) with dolomite (3) in a stirred reactor (1) with a temperature in range of 110 to 170 °C, 4-amino-1,2,4-triazole (6) is continuously added in an amount from 0.4% by weight to 4% by weight of the ammonia nitrogen content expected in the resulting fertilizer (17), then the reaction the solution with 4-amino-1,2,4-triazole (8) is further mixed and sent for processing by granulation (9). 2. A method of producing granular ammonium slag with dolomite containing the nitrification inhibitor 4-amino-1,2,4-triazole, characterized in that ammonium sulfate (4) is added to ammonium nitrate (2) with dolomite (3) in an amount from 0.1 to 0.5% by weight, the resulting reaction solution (5) is mixed in the reactor (1) with a temperature in the range of 110 to 170 °C, then 4-amino-1,2,4 is continuously added to it -triazole (6) in an amount from 0.4% by weight to 4% by weight of the ammonia nitrogen content expected in the resulting fertilizer (17), then the reaction solution with 4-amino-1,2,4-triazole (8) is mixed and it is taken for processing by granulation (9). 3. The method according to claims 1a 2, characterized in that the reaction solution with 4-amino-1,2,4-triazole (8) has a temperature in the range from 145 to 155 °C achieved by chemical reaction or additional heating (7). 4. The method according to claims 1a 2, characterized in that the reaction solution with 4-amino-1,2,4-triazole (8) is mixed in a time span of 5 to 90 minutes. 5. The method according to claims la 2, characterized in that after granulation (9) the wet granulate (11) is moved to drying (12), after drying it is further sorted (13), cooled (14) and surface treated (15) substance against dustiness and caking (16), thereby creating a ready-made fertilizer (17) granulated ammonium nitrate with dolomite containing the nitrification inhibitor 4-amino-1,2,4-triazole.