Anti-blocking agent for agricultural calcium ammonium nitrate fertilizer as well as preparation method and application of anti-blocking agent

Abstract

The invention relates to the technical field of agricultural fertilizers, in particular to an anti-blocking agent technology, and more particularly relates to an agricultural calcium ammonium nitrate fertilizer anti-blocking agent as well as a preparation method and an application technology thereof. The anti-blocking agent comprises the following components in percentage by weight: 10.0%-20.0% of alkylphenol polyoxyethylene ether phosphate; 8.0% to 16.0% of dodecyl benzene sulfonic acid triethanolamine salt; 7.0%-15.0% of ammonium polyacrylate salt; 4.0% to 10.0% of fatty alcohol polyoxyethylene ether methyl silane; 20.0% to 70.0% of a polyhydric alcohol; the sum of the mass percentages of all the components is 100%. The anti-blocking agent provided by the invention is excellent in performance, is added to the rear end of a granulation process in the production process of the agricultural calcium ammonium nitrate fertilizer, and can meet the requirement that the agricultural calcium ammonium nitrate fertilizer is kept loose within 6-9 months (in a normal state) after being uniformly mixed with fertilizer particles.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of agricultural fertilizer, in particular to the anti-caking agent technology, more particularly to an agricultural calcium ammonium nitrate anti-caking agent and a preparation method and application thereof. BACKGROUND

[0002] The agricultural calcium ammonium nitrate, also known as nitramite or ammoniated calcium nitrate, has a chemical formula of 5Ca(NO3)2·NH4NO3·10H2O and is a new type of solid water-soluble fertilizer. The agricultural calcium ammonium nitrate contains calcium and nitrogen (nitrate nitrogen and ammonium nitrogen) and has good water solubility. It is suitable for various soils, especially for acid soils and saline-alkali soils. It is suitable for a variety of crops, especially for fruit trees, vegetables, flowers and the like.

[0003] The agricultural calcium ammonium nitrate has been widely used in foreign countries, especially in Western Europe. After China included ammonium nitrate in the range of explosives in 2002 and prohibited the sale of ammonium nitrate as a fertilizer, the calcium ammonium nitrate began to attract attention as a substitute for ammonium nitrate. At present, many ammonium nitrate plants in China have shifted to producing calcium ammonium nitrate, and many newly built calcium ammonium nitrate production devices have also been put into operation. The production of calcium ammonium nitrate has made great progress in China. In terms of industrial layout, the production capacity of calcium ammonium nitrate is concentrated in Henan, Hebei, Guizhou, Shandong, Liaoning and Hubei provinces. The leading enterprises in these regions occupy a large market share. According to the statistics of the Nitrocalcite and Magnesium Fertilizer Branch of the China Nitrogenous Fertilizer Industry Association, the production of calcium ammonium nitrate in China exceeded 2 million tons in 2023, and the market size reached tens of billions of yuan. As of the end of 2024, the domestic production capacity of calcium ammonium nitrate was 2.79 million tons, up 7% year on year.

[0004] There are mainly two production processes for domestic agricultural calcium ammonium nitrate. One is the crystallization method, which uses nitric acid, limestone and ammonium nitrate solution as main raw materials, combines them, evaporates, granulates, cools and forms the product. This method is mainly used for ammonium nitrate plants to produce calcium ammonium nitrate. The other is the by-product of nitric acid phosphate fertilizer, which is a solid water-soluble fertilizer formed by neutralizing the by-product of calcium nitrate (containing excess nitric acid) and ammonia after combining the by-product of calcium nitrate (containing excess nitric acid) and calcium carbonate.

[0005] The agricultural calcium ammonium nitrate and its use procedures (NY / T 2269-2020) stipulate the physical and chemical indicators and detection methods of agricultural calcium ammonium nitrate. Most production enterprises produce agricultural calcium ammonium nitrate in accordance with this standard, and some production enterprises produce agricultural calcium ammonium nitrate in accordance with the standard of medium element water-soluble fertilizer (NY 2266-2012). The water content index in both standards is ≤3.0%, and the water content index is very strict.

[0006] Calcium ammonium nitrate for agricultural use has strong hygroscopicity and caking property. From the molecular formula, calcium ammonium nitrate is mixed by ammonium nitrate and calcium nitrate in a ratio of 1:5. From the micro-morphology analysis, it belongs to a kind of complex salt, i.e. Ca5·NH4·(NO3) 11 ·10H2O. Its hygroscopic and caking properties can be explained from three aspects: (1) Ammonium nitrate has strong hygroscopicity and is easy to caking; it has high surface energy on the surface of ammonium nitrate particles, and has a strong tendency to adsorb external water molecules, which are combined with hydrogen bonds through electrostatic attraction; the surface of ammonium nitrate crystal has a multi-capillary pore structure, containing a large porosity and capillary pore radius, which all cause ammonium nitrate to have a strong adsorption of water. For example, at 30℃, the relative critical humidity of ammonium nitrate is 59.4%, and at 40℃, it is 52.5%; (2) Calcium nitrate tetrahydrate is a colorless transparent monoclinic crystal in normal state, which is extremely easy to absorb moisture and deliquesce in air. Experimental data show that under the same conditions, at 10℃, the moisture absorption change rate of calcium nitrate tetrahydrate increases with time, while when the temperature is higher than 20℃, the moisture absorption change rate of calcium nitrate tetrahydrate continues to decrease with time, and 3h will appear water reduction, i.e. dehydration phenomenon; (3) Ammonium nitrate crystal exists in multiple crystal forms, each of which must exist within a certain temperature range; when the temperature is higher than 32.3℃, the crystal form changes from type III to type IV, and the crystal lattice volume changes greatly, almost doubling; under the condition of pressure, this deformation reorganizes into a new crystal form process, which is easy to make the crystal break and pulverize, and make the crystal contact more closely and caking.

[0007] Overall, due to the water absorption and moisture absorption characteristics of ammonium nitrate crystal, the moisture absorption and dehydration characteristics of calcium nitrate tetrahydrate, and the crystal form transformation characteristics of ammonium nitrate crystal, the calcium ammonium nitrate fertilizer for agricultural use is easy to absorb moisture and caking. The manufacturers often control the technical indicators of raw materials, improve the production process conditions, optimize the packaging specifications, and improve the storage and transportation conditions to slow down the caking problem, but the effect is very small, especially in the high temperature and high humidity season, the caking is quite serious.

[0008] The existing technology proposes an anti-caking agent, which is mainly for compound fertilizer. This kind of product is generally divided into two categories, one is an oily paste anti-caking agent composed of animal and vegetable fats and oils and mineral oil; the other is an inert powder based on physical isolation, such as kaolin, diatomite, talc, etc. In recent years, the anti-caking agent for full water-soluble fertilizer also shows speciality. For the new variety of calcium ammonium nitrate for agricultural use, due to its complex caking mechanism, serious caking phenomenon and relatively high product technical index requirements (such as water content ≤3.0%, water insoluble content ≤0.5%, etc.), the traditional fertilizer anti-caking agent does not have the corresponding solving ability due to its shortcomings in formula composition, water solubility, appearance, anti-caking effect, etc.

[0009] Furthermore, on the one hand, there are differences in understanding among those skilled in the art; on the other hand, the inventors studied a large number of documents and patents when making this invention, but due to space limitations, not all details and contents were listed in detail. However, this does not mean that the present invention does not possess the features of these prior art. On the contrary, the present invention already possesses all the features of the prior art, and the applicant reserves the right to add relevant prior art to the background art. Summary of the Invention

[0010] To address the aforementioned technical problems, this invention proposes an anti-caking agent for agricultural ammonium calcium nitrate fertilizer.

[0011] One objective of this invention is to provide an anti-caking agent for agricultural ammonium calcium nitrate fertilizer, which comprises the following raw material components by weight percentage: Alkylphenol polyoxyethylene ether phosphate 10.0%–20.0%; Triethanolamine dodecylbenzenesulfonate salt: 8.0%–16.0%; Ammonium polyacrylate 7.0%–15.0%; Fatty alcohol polyoxyethylene ether methylsilane 4.0%–10.0%; Polyols 20.0%–70.0%; The sum of the mass percentages of all components is 100%.

[0012] According to a preferred embodiment, the agricultural ammonium calcium nitrate fertilizer anti-caking agent comprises, by weight percentage, the following raw material components: Alkylphenol polyoxyethylene ether phosphate 12.0%–18.0%; Triethanolamine dodecylbenzenesulfonate salt 9.0%–15.0%; Ammonium polyacrylate 8.0%–14.0%; Fatty alcohol polyoxyethylene ether methylsilane 5.0%–9.0%; Polyols 22.0%–68.0%; The sum of the mass percentages of all components is 100%.

[0013] According to a preferred embodiment, the alkylphenol polyoxyethylene ether phosphate is nonylphenol polyoxyethylene ether phosphate monoester. The molecular formula of nonylphenol polyoxyethylene ether phosphate monoester is C9H. 19 -C6H4-O-(CH2CH2O) n PO(OH)2, with a degree of polymerization n of 3~30.

[0014] According to a preferred embodiment, the molecular formula of the ammonium polyacrylate is as follows: The degree of polymerization, n, is 50~200.

[0015] According to a preferred embodiment, the molecular formula of fatty alcohol polyoxyethylene ether methylsilane is CH3Si[(CH2CH2O)]. n OR]3, with a degree of aggregation n ranging from 5 to 50.

[0016] According to a preferred embodiment, the polyol is diethylene glycol.

[0017] One objective of this invention is to provide a method for preparing an anti-caking agent for agricultural ammonium calcium nitrate fertilizer, which includes the following steps: S1. Solvent preparation: Add the solvent carrier polyol to the reaction vessel according to the above formula ratio of agricultural ammonium calcium nitrate fertilizer anti-caking agent, start stirring and heat up; S2, Compounding and Fusion: Using the above-mentioned formulation ratio of agricultural ammonium calcium nitrate fertilizer anti-caking agent, alkylphenol polyoxyethylene ether phosphate, triethanolamine dodecylbenzene sulfonate, ammonium polyacrylate, and fatty alcohol polyoxyethylene ether methylsilane are added to the solvent in S1, and stirred to mix thoroughly to obtain agricultural ammonium calcium nitrate fertilizer anti-caking agent.

[0018] According to a preferred embodiment, in S1, the stirring conditions are: continuous stirring at a speed of 50 r / min, heating to 40°C and maintaining the temperature until the mixture is uniformly stirred.

[0019] According to a preferred embodiment, in S2, the stirring conditions are: stirring at 50 r / min for 30 min at 40°C.

[0020] One of the objectives of this invention is to provide an anti-caking agent for agricultural ammonium calcium nitrate fertilizer in the preparation of fertilizers. The anti-caking agent is the above-mentioned anti-caking agent for agricultural ammonium calcium nitrate fertilizer or an anti-caking agent for agricultural ammonium calcium nitrate fertilizer prepared based on the above preparation method.

[0021] One of the objectives of this invention is to provide a fertilizer comprising the above-mentioned anti-caking agent for agricultural ammonium calcium nitrate fertilizer or an anti-caking agent for agricultural ammonium calcium nitrate fertilizer prepared based on the above-mentioned preparation method.

[0022] According to a preferred embodiment, the amount of anti-caking agent added, by mass fraction, is 1.0‰ to 3.0‰. Preferably, the amount of anti-caking agent added, by mass fraction, is 1.0‰. Preferably, the amount of anti-caking agent added, by mass fraction, is 2.0‰. Preferably, the amount of anti-caking agent added, by mass fraction, is 3.0‰.

[0023] According to a preferred embodiment, the anti-caking agent is directly added to the downstream end of the granulation process and uniformly mixed with the fertilizer granules. Preferably, the mixing method involves uniformly spraying the anti-caking agent onto the surface of agricultural ammonium nitrate calcium fertilizer at the granulator outlet.

[0024] The beneficial effects of this invention include the following four points.

[0025] 1. In the anti-caking agent of this invention, the selected raw material components are surfactant materials. Alkylphenol polyoxyethylene ether phosphate, triethanolamine dodecylbenzenesulfonate, ammonium polyacrylate, and fatty alcohol polyoxyethylene ether methylsilane are anionic or nonionic surfactants, which have the functions of dispersing, lubricating, penetrating, and spreading. As shown in the agglomeration breaking pressure in the following examples, the selected surfactants also have a synergistic effect when used in combination.

[0026] 2. In the anti-caking agent of this invention, all the raw material components are in liquid form. Liquid form anti-caking agents are more convenient to add and use, and are easier to spread and penetrate to the surface of agricultural ammonium nitrate calcium fertilizer granules, which is more conducive to the function of the anti-caking agent.

[0027] 3. The proportions of each component in the anti-caking agent provided by this invention enable the components to work synergistically to form an effective anti-caking effect. If any component exceeds the specified range, or if any component is replaced or missing, the anti-caking effect of the anti-caking agent will be poor. For example, when the mass proportions of alkylphenol polyoxyethylene ether phosphate in Comparative Example 1, ammonium polyacrylate in Comparative Example 2, fatty alcohol polyoxyethylene ether methylsilane in Comparative Example 3, and polyol in Comparative Example 4 exceed the ranges described in this invention, and when alkylphenol polyoxyethylene ether phosphate is replaced with alkylphenol polyoxyethylene ether sulfonate in Comparative Example 5, triethanolamine dodecylbenzenesulfonate is replaced with sodium dodecylbenzenesulfonate in Comparative Example 6, ammonium polyacrylate is removed in Comparative Example 7, and fatty alcohol polyoxyethylene ether methylsilane is removed in Comparative Example 8, the anti-caking effect of the anti-caking agent decreases sharply.

[0028] 4. The anti-caking agent provided by this invention has excellent performance. Agricultural ammonium calcium nitrate fertilizer, after adding the anti-caking agent provided by this invention, can remain loose for 6-9 months (under normal conditions). The anti-caking agent provided by this invention will not affect the quality of agricultural ammonium calcium nitrate fertilizer, nor will it harm the soil or crops when applied to agricultural fertilization.

[0029] In summary, the anti-caking agent of this invention, a liquid form composed of specific surfactants, delivers significant beneficial effects when applied to calcium ammonium nitrate fertilizer. Its liquid properties ensure that the anti-caking agent forms an ultra-thin, uniform, and robust hydrophobic coating on the surface of fertilizer granules, effectively preventing moisture and humidity from penetrating into the granules and reducing hardening caused by surface dissolution and recrystallization between granules. Simultaneously, the liquid formulation itself possesses excellent wetting and penetrability, making application simple and quick; only a small amount is needed to achieve the desired anti-caking effect. Compared to solid powdered anti-caking agents, it produces no dust pollution, is easier to disperse evenly, and is less prone to detachment. This anti-caking agent excels in inhibiting the hygroscopic solidification of calcium ammonium nitrate. It not only maintains the fertilizer in a loose and free-flowing state for a long time, significantly reducing losses and handling problems caused by caking during storage and transportation, and ensuring the stability of the fertilizer's physical properties, but also ensures efficient and smooth field fertilization operations, avoiding clogging of fertilization equipment. Ultimately, this highly efficient anti-caking property helps maintain the physical availability and uniform distribution of key nutrients (nitrogen and calcium) in calcium ammonium nitrate, promoting effective absorption and utilization by crops, thereby supporting the maximization of fertilizer efficiency. Detailed Implementation

[0030] In the description of this invention, terminology is used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly defined.

[0031] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods; the materials, reagents or instruments used, unless otherwise specified by the manufacturer, are all commercially available reagents and materials; the conditions not specified in the examples are all carried out according to conventional conditions or conditions recommended by the manufacturer. At the same time, the present invention does not limit the source of the raw materials used. Unless otherwise specified, the raw materials used in the present invention are all commercially available products in this technical field.

[0032] In this application, alkylphenol polyoxyethylene ether phosphate, triethanolamine dodecylbenzenesulfonic acid salt, ammonium polyacrylate, and fatty alcohol polyoxyethylene ether methylsilane are all surfactants, and their simultaneous use has a synergistic effect. Alkylphenol polyoxyethylene ether phosphate monoester, an anionic surfactant, is a light yellow viscous liquid with good wetting, penetration, detergency, emulsification, and dispersion properties. It is stable in acidic and alkaline solutions, resistant to electrolytes, has good thermal stability, and good compatibility. Triethanolamine dodecylbenzenesulfonic acid salt, an anionic surfactant, is a pale yellow transparent liquid with excellent lubricating properties. Its molecular structure contains lipophilic alkyl chains and hydrophilic sulfonic acid groups, giving it excellent wetting, emulsification, and dispersion functions, and it is often used for anti-caking treatment of ammonium salt fertilizers. Ammonium polyacrylate, an anionic surfactant, is a polymeric dispersant and a pale yellow liquid. Ammonium polyacrylate dispersants possess excellent dispersing properties, effectively dispersing various powders and particles. This substance achieves efficient dispersion of powders and particles through an electrostatic stabilization mechanism, resulting in superior flowability. Fatty alcohol polyoxyethylene ether methylsilane, a nonionic surfactant, has low surface tension, reducing surface tension on liquid surfaces and making it easier for liquids to wet solid surfaces. Polyols are commonly used organic solvents, characterized by strong dissolving power, low volatility, and good compatibility with many organic components.

[0033] Example 1 The components (mass ratio) of the anti-caking agent 1 in this embodiment are as follows: Alkylphenol polyoxyethylene ether phosphate 20.0%; Triethanolamine dodecylbenzenesulfonate 8.0%; Ammonium polyacrylate 7.0%; Fatty alcohol polyoxyethylene ether methylsilane 10.0%; Polyols 55.0%; Preparation method of anti-caking agent for agricultural ammonium calcium nitrate fertilizer: Add solvent carrier polyol to the reaction vessel in proportion, start stirring at 50 r / min, heat to 40℃ and maintain; add alkylphenol polyoxyethylene ether phosphate, triethanolamine dodecylbenzene sulfonate, ammonium polyacrylate, and fatty alcohol polyoxyethylene ether methylsilane to the solvent carrier in the above step in proportion, maintain 40℃, stir for 30 min at 50 r / min, mix thoroughly to obtain the finished anti-caking agent. Mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer: The anti-caking agent is added to the agricultural ammonium calcium nitrate fertilizer at the end of the granulation process by spraying and mixed evenly.

[0034] Example 2 The components (mass ratio) of the anti-caking agent 2 in this embodiment are as follows: Alkylphenol polyoxyethylene ether phosphate 18.0%; Triethanolamine dodecylbenzenesulfonate 9.0%; Ammonium polyacrylate 8.0%; Fatty alcohol polyoxyethylene ether methylsilane 9.0%; Polyols 56.0%; The preparation method of the anti-caking agent for agricultural ammonium calcium nitrate fertilizer is the same as in Example 1.

[0035] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0036] Example 3 The components (mass ratio) of the anti-caking agent 3 in this embodiment are as follows: Alkylphenol polyoxyethylene ether phosphate 14.5%; Triethanolamine dodecylbenzenesulfonate 14.0%; 10.5% ammonium polyacrylate; Fatty alcohol polyoxyethylene ether methylsilane 6.0%; Polyols 55.0%; The preparation method of the anti-caking agent for agricultural ammonium calcium nitrate fertilizer is the same as in Example 1.

[0037] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0038] Example 4 The components (mass ratio) of the anti-caking agent 4 in this embodiment are as follows: Alkylphenol polyoxyethylene ether phosphate 16.5%; Triethanolamine dodecylbenzenesulfonate 10.0%; Ammonium polyacrylate 12.5%; Fatty alcohol polyoxyethylene ether methylsilane 8.0%; Polyols 53.0%; The preparation method of the anti-caking agent for agricultural ammonium calcium nitrate fertilizer is the same as in Example 1.

[0039] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0040] Example 5 The components (mass ratio) of the anti-caking agent 5 in this embodiment are as follows: Alkylphenol polyoxyethylene ether phosphate 10.0%; Triethanolamine dodecylbenzenesulfonate 16.0%; Ammonium polyacrylate 14.0%; Fatty alcohol polyoxyethylene ether methylsilane 5.0%; Polyols 55.0%; The preparation method of the anti-caking agent for agricultural ammonium calcium nitrate fertilizer is the same as in Example 1.

[0041] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0042] Example 6 Alkylphenol polyoxyethylene ether phosphate 12.0%; Triethanolamine dodecylbenzenesulfonate 15.0%; Ammonium polyacrylate 15.0%; Fatty alcohol polyoxyethylene ether methylsilane 4.0%; Polyols 54.0%; The preparation method of the anti-caking agent for agricultural ammonium calcium nitrate fertilizer is the same as in Example 1.

[0043] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0044] Comparative Example 1 The components (mass ratio) of anti-caking agent 7 in this comparative example are as follows: Alkylphenol polyoxyethylene ether phosphate 25.0%; Triethanolamine dodecylbenzenesulfonate 15.0%; Ammonium polyacrylate 11.0%; Fatty alcohol polyoxyethylene ether methylsilane 5.0%; Polyols 44.0%; The preparation method of the anti-caking agent for agricultural ammonium calcium nitrate fertilizer is the same as in Example 1.

[0045] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0046] Comparative Example 2 The components (mass ratio) of anti-caking agent 8 in this comparative example are as follows: Alkylphenol polyoxyethylene ether phosphate 20.0%; Triethanolamine dodecylbenzenesulfonate 12.0%; Ammonium polyacrylate 20.0%; Fatty alcohol polyoxyethylene ether methylsilane 6.0%; Polyols 42.0%; The preparation method of the anti-caking agent for agricultural ammonium calcium nitrate fertilizer is the same as in Example 1.

[0047] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0048] Comparative Example 3 The components (mass ratio) of anti-caking agent 9 in this comparative example are as follows: Alkylphenol polyoxyethylene ether phosphate 18.0%; Triethanolamine dodecylbenzenesulfonate 14.0%; Ammonium polyacrylate 10.0%; Fatty alcohol polyoxyethylene ether methylsilane 16.0%; Polyols 42.0%; The preparation method of the anti-caking agent for agricultural ammonium calcium nitrate fertilizer is the same as in Example 1.

[0049] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0050] Comparative Example 4 The components (mass ratio) of anti-caking agent 10 in this comparative example are as follows: Alkylphenol polyoxyethylene ether phosphate 10.0%; Triethanolamine dodecylbenzenesulfonate 4.0%; Ammonium polyacrylate 6.0%; Fatty alcohol polyoxyethylene ether methylsilane 5.0%; Polyols 75.0%; The preparation method of the anti-caking agent for agricultural ammonium calcium nitrate fertilizer is the same as in Example 1.

[0051] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0052] Comparative Example 5 Alkylphenol polyoxyethylene ether sulfonate 18.0%; Triethanolamine dodecylbenzenesulfonate 9.0%; Ammonium polyacrylate 8.0%; Fatty alcohol polyoxyethylene ether methylsilane 9.0%; Polyols 56.0%; This embodiment serves as a comparative example of the present invention. The only difference between this embodiment and Example 2 is that the alkylphenol polyoxyethylene ether phosphate component of the agricultural ammonium nitrate calcium fertilizer anti-caking agent is replaced with alkylphenol polyoxyethylene ether sulfonate instead of alkylphenol polyoxyethylene ether phosphate. The remaining components, dosages, and production processes are the same.

[0053] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0054] Comparative Example 6 Alkylphenol polyoxyethylene ether phosphate 18.0%; Sodium dodecylbenzenesulfonate 9.0%; Ammonium polyacrylate 8.0%; Fatty alcohol polyoxyethylene ether methylsilane 9.0%; Polyols 56.0%; This embodiment serves as a comparative example of the present invention. The only difference between this embodiment and Example 2 is that the agricultural ammonium calcium fertilizer anti-caking agent component does not contain triethanolamine dodecylbenzenesulfonate salt, but is replaced by sodium dodecylbenzenesulfonate. The remaining components, dosages, and production processes are the same.

[0055] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0056] Comparative Example 7 Alkylphenol polyoxyethylene ether phosphate 18.0%; Triethanolamine dodecylbenzenesulfonate 9.0%; Fatty alcohol polyoxyethylene ether methylsilane 9.0%; Polyols 64.0%; This embodiment serves as a comparative example of the present invention. The only difference between this embodiment and Example 2 is that the ammonium polyacrylate salt is not added to the anti-caking agent component of agricultural ammonium calcium nitrate fertilizer, and polyol is used instead as the solvent carrier. The other components, dosages, and production processes are the same.

[0057] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0058] Comparative Example 8 Alkylphenol polyoxyethylene ether phosphate 18.0%; Triethanolamine dodecylbenzenesulfonate 9.0%; Ammonium polyacrylate 8.0%; Polyols 65.0%; This embodiment serves as a comparative example of the present invention. The only difference between this embodiment and Example 2 is that the fatty alcohol polyoxyethylene ether methylsilane was not added to the anti-caking agent component of agricultural ammonium calcium fertilizer; instead, a solvent carrier polyol was used instead. The remaining components, dosages, and production processes are the same.

[0059] The mixing method of agricultural ammonium calcium nitrate fertilizer with fertilizer is the same as in Example 1.

[0060] Test results The anti-caking agents from the above embodiments and comparative examples were uniformly mixed into agricultural ammonium nitrate calcium fertilizer experimental samples at a certain dosage. Samples were taken and molded into cylinders of Φ50×70 mm under a pressure of 1.5 MPa. These cylinders were then placed in a test chamber at 80% RH and 60℃ for 12 hours under the same pressure; subsequently, they were placed in an environment at 60% RH and 40℃ for 12 hours under the same pressure, and this cycle was repeated four times. The samples were then left at room temperature for 24 hours to obtain the final sample. The crushing pressure of this sample was then measured on an electronic pressure testing machine. The higher the crushing pressure, the more severe the agglomeration and the worse the effect of the anti-caking agent.

[0061] The samples of agricultural ammonium calcium nitrate fertilizer obtained by adding the anti-caking agents of the above embodiments and comparative examples were subjected to crushing pressure tests, and parallel blank samples were used for comparison. The test results are shown in Table 1 and Table 2.

[0062] Table 1 shows the agglomeration breaking pressure data when the anti-caking agent dosage is 1.8 (kg / T).

[0063] Table 1

[0064] Table 2 shows the agglomeration breaking pressure data when the anti-caking agent dosage is 2.5 (kg / T).

[0065] Table 2

[0066] Experimental results demonstrate that agricultural ammonium calcium nitrate fertilizer samples with the added anti-caking agent of this invention exhibit significantly reduced agglomeration and breakup pressure compared to the blank control under the same environmental temperature, humidity, and pressure conditions. Furthermore, the proportions of each component in the anti-caking agent system formulation play a crucial role in its anti-caking performance. Within this specific proportion range, experiments show that the addition of the anti-caking agent of this invention can substantially reduce the agglomeration phenomenon in agricultural ammonium calcium nitrate fertilizer, achieving the desired anti-caking effect. While the anti-caking agents in the comparative examples, exceeding the proportion range of this invention, also exhibit some anti-caking performance, the effect falls far short of the ideal level.

[0067] It should be noted that the specific embodiments described above are exemplary, and those skilled in the art can devise various solutions inspired by the disclosure of this invention. These solutions all fall within the scope of this invention and its protection. Those skilled in the art should understand that this specification is illustrative and not intended to limit the scope of the claims. The scope of protection of this invention is defined by the claims and their equivalents.

Claims

1. An anti-caking agent for agricultural ammonium calcium nitrate fertilizer, characterized in that, By weight percentage, it includes the following raw material components: Alkylphenol polyoxyethylene ether phosphate 10.0%–20.0%; Triethanolamine dodecylbenzenesulfonate salt: 8.0%–16.0%; Ammonium polyacrylate 7.0%–15.0%; Fatty alcohol polyoxyethylene ether methylsilane 4.0%–10.0%; Polyols 20.0%–70.0%; The sum of the mass percentages of all components is 100%.

2. The agricultural ammonium calcium nitrate fertilizer anti-caking agent according to claim 1, characterized in that, By weight percentage, it includes the following raw material components: Alkylphenol polyoxyethylene ether phosphate 12.0%–18.0%; Triethanolamine dodecylbenzenesulfonate salt 9.0%–15.0%; Ammonium polyacrylate 8.0%–14.0%; Fatty alcohol polyoxyethylene ether methylsilane 5.0%–9.0%; Polyols 22.0%–68.0%; The sum of the mass percentages of all components is 100%.

3. An anti-caking agent for agricultural ammonium calcium nitrate fertilizer according to claim 1 or 2, characterized in that, The alkylphenol polyoxyethylene ether phosphate is nonylphenol polyoxyethylene ether phosphate monoester.

4. An anti-caking agent for agricultural ammonium calcium nitrate fertilizer according to claim 1 or 2, characterized in that, The polyol is diethylene glycol.

5. A method for preparing an anti-caking agent for agricultural ammonium calcium nitrate fertilizer, characterized in that, Includes the following steps: S1. Solvent preparation: Add the solvent carrier polyol to the reaction vessel according to the formulation ratio of the agricultural ammonium calcium nitrate fertilizer anti-caking agent according to any one of claims 1 to 4, start stirring, and heat up; S2, Compounding and Fusion: Using the formulation ratio of the agricultural ammonium nitrate calcium fertilizer anti-caking agent according to any one of claims 1 to 4, alkylphenol polyoxyethylene ether phosphate, triethanolamine dodecylbenzene sulfonate, ammonium polyacrylate, and fatty alcohol polyoxyethylene ether methylsilane are added to the solvent in S1, and stirring is maintained to fully mix them to obtain the agricultural ammonium nitrate calcium fertilizer anti-caking agent.

6. The preparation method according to claim 5, characterized in that, In S1, the stirring conditions are as follows: continuous stirring at a speed of 50 r / min, heating to 40℃ and maintaining that temperature until the mixture is homogeneous.

7. The preparation method according to claim 5, characterized in that, In S2, the stirring conditions are: stirring at 50 r / min for 30 min at 40℃.

8. The application of an agricultural ammonium nitrate calcium fertilizer anti-caking agent in fertilizer preparation, characterized in that, The anti-caking agent is the agricultural ammonium nitrate calcium fertilizer anti-caking agent as described in any one of claims 1 to 4, or the agricultural ammonium nitrate calcium fertilizer anti-caking agent prepared based on the preparation method described in any one of claims 5 to 7.

9. A fertilizer, characterized in that, It includes the agricultural ammonium nitrate calcium fertilizer anti-caking agent as described in any one of claims 1 to 4, or the agricultural ammonium nitrate calcium fertilizer anti-caking agent prepared based on the preparation method described in any one of claims 5 to 7.

10. The fertilizer according to claim 9, characterized in that, The amount of the anti-caking agent added is 1.0‰ to 3.0‰ by mass fraction.

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