Fertilizer synergist for promoting absorption and preparation method thereof

Abstract

The invention belongs to the technical field of fertilizers, and particularly relates to a fertilizer synergist for promoting absorption and a preparation method thereof. The fertilizer synergist is prepared from the following components in parts by mass: 0.3 to 2.5 parts of dicyandiamide, 1 to 1.5 parts of potassium fulvate, 2.5 to 4.5 parts of phytic acid, 3.5 to 6 parts of N-butyl thiophosphoric triamide, 1 to 3 parts of magnesium sulfate, 1 to 3 parts of ferric ammonium sulfate, 3.5 to 5.5 parts of animal hair, 5 to 6 parts of bagasse, 2.5 to 6 parts of polyvinyl alcohol, 1.5 to 3 parts of gamma-polyglutamic acid, 0.6 to 0.9 part of glyceryl monostearate, 0.02 to 0.1 part of vitamin B, 0.08 to 0.2 part of ethylene diamine tetraacetic acid and 85 to 95 parts of water. The preparation method comprises the following steps: carrying out pretreatment, alkaline hydrolysis and reduction on animal wool, and then carrying out shearing emulsification and grafting reaction on the animal wool and a coating component to obtain coating liquid; and continuously adding the remaining components into the coating liquid to obtain the fertilizer synergist. When the prepared fertilizer synergist is specifically applied, the problems that the stability of the fertilizer synergist in high-temperature and acid-base environments and the compatibility among components are insufficient are effectively solved.

Description

Technical Field

[0001] This invention belongs to the field of fertilizer technology, specifically relating to a fertilizer synergist that promotes absorption and its preparation method. Background Technology

[0002] Fertilizer synergists are a general term for mixtures that assist fertilizers in exerting their effects. They can improve nutrient supply, promote plant nutrient absorption, or regulate soil microorganisms and enzyme activity. Fertilizer synergists can be broadly categorized into chemically synthesized types, such as urease inhibitors and nitrification inhibitors, and natural / biological types, such as humic acid, alginic acid, amino acids, and microorganisms. In practical applications, problems with these synergists often focus on their stability in high-temperature and acidic / alkaline environments, as well as insufficient compatibility between components. For example, urease inhibitors degrade into nitrogen, phosphorus, and sulfur elements in the soil after 1-2 weeks, leading to a sharp drop in urease activity inhibition. Nitrification inhibitors have a longer duration of action in highly acidic soils, but a relatively shorter duration in slightly alkaline soils. This is because high temperatures and acidic / alkaline environments can sometimes increase microbial activity, causing premature disintegration and degradation of components such as urease inhibitors and nitrification inhibitors in the soil.

[0003] Chinese patent CN106431719A discloses a fertilizer synergist, which, by mass parts, is composed of the following components: 6-10 parts of polymeric amino acids, 4-8 parts of ammonium nitrohumate, 3-5 parts of Bacillus subtilis, 5-7 parts of oxalic acid, 6-10 parts of magnesium sulfate, 4-6 parts of zeolite powder, 3-5 parts of ammonium humate, 2-4 parts of anhydrous borax, 4-6 parts of complexed rare earth elements, and 1-3 parts of indoleacetic acid.

[0004] In this patent, Bacillus subtilis, when mixed with anhydrous borax, complexed rare earth elements, etc., is at risk of inactivation under normal temperature storage conditions, and the compatibility of the components is poor. In addition, indoleacetic acid, as a natural plant growth hormone, is chemically unstable and is easily degraded in light, high temperature or alkaline environments, affecting its effectiveness.

[0005] Chinese patent CN106831099A discloses a fertilizer slow-release synergist, which, by mass parts, consists of the following components: 20-30 parts coal slime, 10-12 parts cobalt chloride, 10-20 parts corn cob, 10-15 parts gypsum powder, 5-7 parts sea asbestos wool, 4-6 parts vitamin B4, 4-6 parts salicylic acid, 8-10 parts fish washing water, 0.3-0.5 parts urease inhibitor, and 0.1-0.3 parts nitrification inhibitor.

[0006] In this patent, cobalt chloride and gypsum powder are highly hygroscopic components, which are prone to moisture absorption during long-term storage, leading to the loss of effective ingredients. Summary of the Invention

[0007] The purpose of this invention is to provide a fertilizer synergist that promotes absorption, addressing the shortcomings of fertilizer synergists in terms of stability under high temperature and acid / alkali environments, as well as the compatibility between components; this invention also provides a method for preparing the fertilizer synergist.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The fertilizer synergist for promoting absorption described in this invention comprises, by weight, the following components: 0.3-2.5 parts dicyandiamide, 1-1.5 parts potassium humate, 2.5-4.5 parts phytic acid, 3.5-6 parts N-butylthiophosphoric triamine, 1-3 parts magnesium sulfate, 1-3 parts ferric ammonium sulfate, 3.5-5.5 parts animal hair, 5-6 parts sugarcane bagasse, 2.5-6 parts polyvinyl alcohol, 1.5-3 parts γ-polyglutamic acid, 0.6-0.9 parts glyceryl monostearate, 0.02-0.1 parts vitamin B, 0.08-0.2 parts disodium ethylenediaminetetraacetate, and 85-95 parts water.

[0009] The preparation method of the fertilizer synergist that promotes absorption according to the present invention includes the following steps: S1. Animal hair, after pretreatment, is added to an alkaline system along with a reducing agent and then heated. S2. Continue to add grafting reagent, catalyst, dicyandiamide, polyvinyl alcohol, γ-polyglutamic acid, glyceryl monostearate and a portion of water, shear emulsify, and then carry out grafting reaction to obtain coating solution; S3. Potassium humate, phytic acid, N-butylthiophosphoric triamine, magnesium sulfate, ferric ammonium sulfate, bagasse, vitamin B, disodium ethylenediaminetetraacetate, and the remaining water are added in batches to the coating solution to obtain the fertilizer synergist.

[0010] in: In S1, the pretreatment involves cutting the animal hair into small pieces and soaking it in an aqueous sodium hydroxide solution with a sodium hydroxide mass fraction of 2-5 wt% and a mass ratio of animal hair to sodium hydroxide solution of 5:(12-16). The soaking time is 20-24 hours.

[0011] In S1, the reducing agent is sodium thiosulfate, the alkaline system is an aqueous solution of sodium hydroxide, and the mass fraction of sodium hydroxide is 12~18wt%; the mass ratio of animal hair, reducing agent and alkaline system is 5:(0.28~0.4):(6~8).

[0012] In S1, the heating treatment temperature is 75~85℃ and the heating treatment time is 1.5~2h.

[0013] In S2, the grafting agent is 1,4-butanediol diglycidyl ether, and the catalyst is triethanolamine.

[0014] The mass ratio of the animal hair, grafting reagent, and catalyst is 5:(0.45~0.55):(0.1~0.16).

[0015] In S2, the mass of water is 2 to 3.5 times the sum of the masses of dicyandiamide, polyvinyl alcohol, γ-polyglutamic acid, and glyceryl monostearate; the shear emulsification rate is 120 to 180 r / min, and the shear emulsification time is 20 to 40 min.

[0016] In S2, the grafting reaction temperature is 55~65℃ and the grafting reaction time is 3~5h.

[0017] In S3, the number of batches is 8 to 12. After each batch is added, stir for 3 to 6 minutes and observe that there is no obvious clumping. Then, continue to add the next batch. After all batches are added, continue to stir for 10 to 20 minutes.

[0018] The application of the fertilizer synergist that promotes absorption described in this invention is its use in fertilizer enhancement treatment: A certain mass of nitrogen fertilizer granules is sieved and then fed into a rotary drum coating machine. The machine is started, and the fertilizer synergist slurry is atomized and sprayed onto the surface of the nitrogen fertilizer granules through a pressurized spraying device. The mass ratio of commercially available nitrogen fertilizer granules to fertilizer synergist is 100:(12~15). The spraying temperature is set to 65~75℃, the spraying rate is 3~5wt% / min of the total mass of fertilizer synergist, and the atomizing air pressure is 6~9.5 bar during spraying. After spraying, dry hot air at 65~75℃ is introduced, and the mixture is stirred for 15~20 minutes. The material is then transferred to a drying device and dried until the moisture content is <2wt%. The granules are sieved to remove agglomerated particles, and the finished synergistic nitrogen fertilizer product is obtained.

[0019] Regarding the promotion of nutrient absorption in fertilizers, the individual components and synergistic effects between the components in the fertilizer synergist of this invention are as follows: Dicyandiamide and N-butylthiophosphoric acid triamine are nitrification / urease inhibitors: Dicyandiamide inhibits the conversion of ammonium nitrogen to nitrate nitrogen in the soil, reducing nitrate nitrogen leaching and denitrification gaseous loss; N-butylthiophosphoric acid triamine inhibits urea hydrolysis, delays ammonium nitrogen release, and reduces the risk of ammonia volatilization. The synergistic effect of the two can extend the effective period of nitrogen fertilizer, reduce ammonium nitrogen loss, make nitrogen supply more in line with crop demand, and improve the crop absorption efficiency of nitrogen.

[0020] Phytic acid, potassium humate, γ-polyglutamic acid, and disodium ethylenediaminetetraacetate have strong chelating abilities, which can chelate trace elements such as calcium, magnesium, iron, and zinc in the soil, preventing them from being fixed and improving crop absorption efficiency. Potassium humate can also stimulate root growth and enhance root vitality. When the four are combined, they can improve the mobility of trace elements and crop absorption efficiency, especially improving the availability of nutrients such as iron and zinc in alkaline soils, which is beneficial to crop absorption.

[0021] After animal hair undergoes alkaline hydrolysis, reduction, and grafting treatment, the modified keratin separated from it can form a porous adsorption structure when preparing synergistic nitrogen fertilizer, which can load nutrients and release them slowly; sugarcane bagasse provides cellulose, improves soil permeability, and enhances water and fertilizer retention capacity. A stable soil moisture environment is conducive to the absorption of nutrients; modified keratin and sugarcane bagasse themselves can degrade naturally and slowly, further providing organic matter for crops.

[0022] Polyvinyl alcohol and γ-polyglutamic acid form a hydrophilic gel network, which enhances the adhesion and film-forming properties of the slurry. After coating fertilizer particles, it reduces the nutrient dissolution rate. This can reduce nutrient loss, prolong fertilizer effect, and improve the rhizosphere microenvironment of crops.

[0023] Magnesium sulfate (provides magnesium), ammonium iron sulfate (provides iron and nitrogen), and B vitamins can enhance crop resistance to stress. Magnesium is a core element of chlorophyll, and iron participates in the synthesis of redox enzymes. When these three are combined, they can prevent nutrient deficiencies and promote crop photosynthesis and energy metabolism.

[0024] The beneficial effects of this invention are as follows: (1) This invention centers on phytic acid, coordinating the phosphoramide group, magnesium and iron ions in N-butylthiophosphoric triamine with the phosphate group in phytic acid. The alkyl chain in N-butylthiophosphoric triamine extends, forming a macromolecular complex. The free ammonium ions in ammonium iron sulfate also play a role in ionization balance and promote the stability of the complex. The macromolecular complex designed in this invention, on the one hand, forms a slow-release effect by reversibly coordinating the phosphoramide group in N-butylthiophosphoric triamine with magnesium and iron ions; on the other hand, the alkyl chain also plays a steric hindrance role, inhibiting free radical contact with the active ingredients (phytic acid, N-butylthiophosphoric triamine, magnesium and iron ions) in the fertilizer synergist. The macromolecular complex improves the stability of the active ingredients in high temperature and acid-base environments through both aspects.

[0025] Disodium ethylenediaminetetraacetate is added as a supplement to prevent the rapid disintegration of macromolecular complexes when small amounts of elements such as iron and magnesium decouple.

[0026] (2) During the shear emulsification process, dicyandiamide, polyvinyl alcohol, γ-polyglutamic acid, and glyceryl monostearate form a micelle system. First, glyceryl monostearate plays a role in interfacial emulsification and hydrophobic regulation, constructing the micelle matrix. Its hydrophobic end groups can inhibit excessive water penetration and delay the swelling of the micelle matrix. Second, the dicyandiamide molecule is composed of cyano, imine, and diamino groups, which have strong polarity and hydrogen bond donor / acceptor capabilities. As a small molecule, it can form a hydrogen bond network with γ-polyglutamic acid and polyvinyl alcohol in the aqueous phase. The cohesion and viscoelasticity of the micelle system are enhanced. Polyvinyl alcohol, as a water-soluble polymer, forms the backbone of the micelle system. The side chains of the polyvinyl alcohol molecular chain have hydroxyl groups that can form hydrogen bonds with water molecules, giving the micelle system good fluidity in the aqueous phase. Finally, γ-polyglutamic acid, as an anionic biopolyelectrolyte, contains a large number of free carboxyl groups and has a strong chelating ability. By incorporating γ-polyglutamic acid into the micelle system, the complexation and homogenization between the macromolecular complex and the micelle system can be further promoted, and phase separation can be prevented.

[0027] (3) In addition, the present invention converts insoluble keratin in animal hair into dispersible polypeptides through alkaline hydrolysis and reduction. In the micelle system, the present invention breaks the original stacking structure of keratin through grafting modification to form a more flexible three-dimensional cross-linked structure. At this time, the hydrophilic groups in the three-dimensional cross-linked structure form a hydrogen bond system with the hydrophilic groups in the micelle system (e.g., the carboxyl group of γ-polyglutamic acid and the hydroxyl group of polyvinyl alcohol). The long chains of polyvinyl alcohol and γ-polyglutamic acid in the micelle system are interspersed in the three-dimensional cross-linked structure to form a cross-linked system. Therefore, the three-dimensional cross-linked structure can better combine with the micelle system.

[0028] Furthermore, during the preparation of enhanced nitrogen fertilizer, a uniform thin film structure is formed during the drying process. This invention designs a crosslinking system and combines it with macromolecular complexes. Through hydrophobic cores to inhibit swelling, hydrogen bond networks and three-dimensional crosslinking structures to enhance cohesion, thin film encapsulation to reduce heat exposure, and polyelectrolyte buffering of pH, the stability of fertilizer enhancers in high-temperature and acid / alkali environments is improved, reducing the probability of premature disintegration and degradation. Furthermore, through micellar homogenization to prevent phase separation, thin film adhesion to enhance coating, and emulsifiers to improve interfacial compatibility, the compatibility between fertilizer enhancer components is enhanced.

[0029] In addition, bagasse, as a natural cellulose, has a surface rich in hydrophilic groups, abundant micropores, and a high specific surface area. As a porous inert framework, it provides physical support and prevents the slurry from settling.

[0030] When phytic acid and other substances are added to the coating solution in batches, the hydrophilic groups on the surface and in the pore structure of bagasse form multiple hydrogen bonds with the macromolecular complex and the hydrophilic groups in the cross-linking system (such as the carboxyl groups of γ-polyglutamic acid and the hydroxyl groups of polyvinyl alcohol). This makes the bagasse, macromolecular complex, and cross-linking system form a unified whole. Using the rigid porous inert framework of bagasse as a template, the flexible three-dimensional network structure of grafted modified keratin and the formed cross-linking system are combined with the macromolecular complex, which enhances the stability of the active ingredients in the macromolecular complex and cross-linking system in complex environments and the compatibility of various types of components in fertilizer synergists. Detailed Implementation

[0031] The present invention will now be described and illustrated in detail with reference to the embodiments.

[0032] The raw materials used in the following examples and comparative examples are all commercially available products. Polyvinyl alcohol was provided by Jinan Chuangshi Chemical Co., Ltd.; γ-polyglutamic acid was provided by Jiangsu Caiwei Biotechnology Co., Ltd.; and wool waste was wool from meat processing, animal fiber primary processing and other processes.

[0033] Example 1 Weigh out 2 kg of dicyandiamide, 1 kg of potassium humate, 4.5 kg of phytic acid, 4.5 kg of N-butylthiophosphoric triamine, 2 kg of magnesium sulfate, 2 kg of ferric ammonium sulfate, 4 kg of wool waste, 6 kg of bagasse, 2.5 kg of polyvinyl alcohol, 3 kg of γ-polyglutamic acid, 0.8 kg of glyceryl monostearate, 0.02 kg of vitamin B, 0.2 kg of disodium ethylenediaminetetraacetate, and 95 kg of water.

[0034] After alkaline hydrolysis and reduction, wool waste is combined with coating components and grafted to obtain a coating solution. The preparation process is as follows: 5 kg of wool waste was shredded and soaked in 15 kg of 3.5 wt% sodium hydroxide aqueous solution at room temperature for 24 hours. It was then removed and washed with tap water. Sodium hydroxide was added to the prepared water to obtain 6 kg of 12 wt% sodium hydroxide aqueous solution. The washed wool waste and 400 g of sodium thiosulfate were then added. The mixture was heated to 85°C and stirred for 1.5 hours. Large particles of residue were then filtered out and set aside.

[0035] Add 550g of 1,4-butanediol diglycidyl ether and 160g of triethanolamine and mix. Then add dicyandiamide, polyvinyl alcohol, γ-polyglutamic acid, glyceryl monostearate and 3.5 times the amount of water to be prepared and mix. Shear at 180r / min for 20min, then reduce the stirring rate to 90r / min and keep warm at 55℃ for 5h. Adjust the pH to neutral to obtain the coating solution.

[0036] While maintaining stirring, add the weighed and prepared phytic acid, N-butylthiophosphoric triamine, magnesium sulfate, ammonium ferric sulfate, sugarcane bagasse, potassium humate, vitamin B, disodium ethylenediaminetetraacetate, and the remaining water to the coating solution in 8 batches. After each batch is added, stir for 3 minutes and observe if there is any obvious clumping. Then continue to add the next batch. After all batches are added, continue stirring for 20 minutes until the slurry is fine, uniform, and free of sediment. The fertilizer synergist is then obtained.

[0037] Example 2 Weigh out 0.3 kg of dicyandiamide, 1.2 kg of potassium humate, 3 kg of phytic acid, 3.5 kg of N-butylthiophosphoric triamine, 1 kg of magnesium sulfate, 3 kg of ferric ammonium sulfate, 5.5 kg of wool waste, 5 kg of sugarcane bagasse, 6 kg of polyvinyl alcohol, 1.5 kg of γ-polyglutamic acid, 0.6 kg of glyceryl monostearate, 0.05 kg of vitamin B, 0.12 kg of disodium ethylenediaminetetraacetate, and 90 kg of water.

[0038] After alkaline hydrolysis and reduction, wool waste is combined with coating components and grafted to obtain a coating solution. The preparation process is as follows: 5 kg of wool waste was shredded and soaked in 12 kg of 5 wt% sodium hydroxide aqueous solution at room temperature for 20 hours. It was then removed and washed with tap water. Sodium hydroxide was added to the prepared water to obtain 8 kg of 14 wt% sodium hydroxide aqueous solution. The washed wool waste and 360 g of sodium thiosulfate were then added, the temperature was raised to 80°C, and the mixture was stirred for 1.8 hours. Large particles of residue were then filtered out and set aside.

[0039] While maintaining stirring, add 500g of 1,4-butanediol diglycidyl ether and 100g of triethanolamine and mix. Then add dicyandiamide, polyvinyl alcohol, γ-polyglutamic acid, glyceryl monostearate and 3 times the amount of water to be prepared and mix. Shear at 160r / min for 40min, then reduce the stirring rate to 80r / min and keep warm at 65℃ for 3h. Adjust the pH to neutral to obtain the coating solution.

[0040] Weigh out the prepared phytic acid, N-butylthiophosphoric triamine, magnesium sulfate, ammonium ferric sulfate, sugarcane bagasse, potassium humate, vitamin B, disodium ethylenediaminetetraacetate, and the remaining water, and add them to the coating solution in 10 batches. After each batch is added, stir for 5 minutes and observe if there is any obvious clumping. Then continue to add the next batch. After all batches are added, continue to stir for 10 minutes until the slurry is fine, uniform, and free of sediment. The fertilizer synergist is then obtained.

[0041] Example 3 Weigh out 2.5 kg of dicyandiamide, 1.5 kg of potassium humate, 2.5 kg of phytic acid, 6 kg of N-butylthiophosphoric triamine, 3 kg of magnesium sulfate, 1 kg of ammonium iron sulfate, 3.5 kg of wool waste, 5.5 kg of sugarcane bagasse, 4 kg of polyvinyl alcohol, 2 kg of γ-polyglutamic acid, 0.9 kg of glyceryl monostearate, 0.1 kg of vitamin B, 0.08 kg of disodium ethylenediaminetetraacetate, and 85 kg of water.

[0042] After alkaline hydrolysis and reduction, wool waste is combined with coating components and grafted to obtain a coating solution. The preparation process is as follows: 5 kg of wool waste was shredded and soaked in 16 kg of 2 wt% sodium hydroxide aqueous solution at room temperature for 22 hours. It was then removed and washed with tap water. Sodium hydroxide was added to the prepared water to obtain 7 kg of 18 wt% sodium hydroxide aqueous solution. The washed wool waste and 280 g of sodium thiosulfate were then added, the temperature was raised to 75°C, and the mixture was stirred for 2 hours. Large particles of residue were then filtered out and set aside.

[0043] Add 450g of 1,4-butanediol diglycidyl ether and 130g of triethanolamine and mix. Then add weighed dicyandiamide, polyvinyl alcohol, γ-polyglutamic acid, glyceryl monostearate and 2 times the mass of water and mix. Shear at 120r / min for 35min, then reduce the stirring rate to 70r / min and keep warm at 60℃ for 4h. Adjust the pH to neutral to obtain the coating solution.

[0044] While maintaining stirring, add the weighed and prepared phytic acid, N-butylthiophosphoric triamine, magnesium sulfate, ammonium ferric sulfate, sugarcane bagasse, potassium humate, vitamin B, disodium ethylenediaminetetraacetate, and the remaining water to the coating solution in 12 batches. After each batch is added, stir for 6 minutes and observe if there is any obvious clumping. Then continue to add the next batch. After all batches are added, continue stirring for 15 minutes until the slurry is fine, uniform, and free of sediment. The fertilizer synergist is then obtained.

[0045] Example 4 Preparation of enhanced nitrogen fertilizer 100 kg of commercially available nitrogen fertilizer granules were screened and then fed into a rotary drum coating machine. The machine was started, and 15 kg of the fertilizer synergist prepared in Example 1 was atomized and sprayed onto the surface of the nitrogen fertilizer granules through a pressurized spraying device. The spraying temperature was set to 75°C, the spraying rate was 5 wt% / min of the total mass of the fertilizer synergist, and the atomizing air pressure was 6 bar during spraying. After spraying, 65°C dry hot air was introduced and the mixture was stirred for another 15 min. The material was then transferred to a drying device and dried until the moisture content was <2 wt%. The agglomerated particles were removed by screening to obtain the finished synergistic nitrogen fertilizer product.

[0046] The rotary drum wrapping machine used in this embodiment is a commercially available device. The same applies to the following embodiments and comparative examples.

[0047] Example 5 100 kg of commercially available nitrogen fertilizer granules were screened and then fed into a rotary drum coating machine. The machine was started, and 12 kg of the fertilizer synergist prepared in Example 1 was atomized and sprayed onto the surface of the nitrogen fertilizer granules through a pressurized spraying device. The spraying temperature was set to 70°C, the spraying rate was 3 wt% / min of the total mass of the fertilizer synergist, and the atomizing air pressure was 9.5 bar during spraying. After spraying, 70°C dry hot air was introduced and the mixture was stirred for another 20 min. The material was then transferred to a drying device and dried until the moisture content was <2 wt%. The agglomerated particles were removed by screening to obtain the finished synergistic nitrogen fertilizer product.

[0048] Example 6 100 kg of commercially available nitrogen fertilizer granules were screened and then fed into a rotary drum coating machine. The machine was started, and 14 kg of the fertilizer synergist prepared in Example 1 was atomized and sprayed onto the surface of the nitrogen fertilizer granules through a pressurized spraying device. The spraying temperature was set to 75°C, the spraying rate was 4 wt% / min of the total mass of the fertilizer synergist, and the atomizing air pressure was 8.5 bar during spraying. After spraying, 75°C dry hot air was introduced and the mixture was stirred for 18 min. The material was then transferred to a drying device and dried until the moisture content was <2 wt%. The agglomerated particles were removed by screening to obtain the finished synergistic nitrogen fertilizer.

[0049] Comparative Example 1 Without adding γ-polyglutamic acid, the rest of the operation process and raw materials used are the same as in Example 1.

[0050] Comparative Example 2 Polyvinyl alcohol was not added, and the remaining operation process and raw materials used were the same as in Example 1.

[0051] Comparative Example 3 Without adding glyceryl monostearate, the remaining procedures and raw materials are the same as in Example 1.

[0052] Comparative Example 4 Phytic acid was not added, and the remaining procedures and raw materials used were the same as in Example 1.

[0053] Comparative Example 5 Without adding N-butylthiophosphoric triamine, the rest of the operation process and raw materials used are the same as in Example 1.

[0054] Comparative Example 6 The coating solution is prepared by directly shearing and emulsifying the coating components. No wool waste is added, and no alkaline hydrolysis or reduction is performed. It is not combined with the coating components for grafting treatment. The remaining operation process and raw materials used are the same as in Example 1.

[0055] Comparative Example 7 Without adding sugarcane bagasse, the rest of the operation process and raw materials used are the same as in Example 1.

[0056] Implementation effect evaluation Collect soil from the top 10-20cm of the ground, sieve it to remove roots and stones, and dry it to obtain dry soil.

[0057] Weigh 1000g of dry soil, add urea solution to it until the pure nitrogen content is 120mg, then add sulfur powder and dilute sulfuric acid until pH=5.4±0.2, finally add 95mg of fertilizer synergist slurry prepared in Example 1, and add an appropriate amount of tap water until the water content in the dry soil is 18±2%, thus obtaining experimental group A1.

[0058] Weigh 1000g of dry soil, add urea solution to it until the pure nitrogen content is 120mg, then add quicklime powder and calcium hydroxide solution until pH=8.0±0.2, finally add 95mg of fertilizer synergist slurry prepared in Example 1, and add an appropriate amount of tap water until the water content in the dry soil is 18±2%, thus obtaining experimental group A2.

[0059] Weigh 1000g of dry soil, add urea solution to it until the pure nitrogen content is 120mg, add 95mg of fertilizer synergist slurry prepared in Example 1, and add an appropriate amount of tap water until the water content in the dry soil is 18±2%, thus obtaining experimental group A3.

[0060] Weigh 1000g of dry soil, add the enhanced nitrogen fertilizer granules prepared in Example 4 (equivalent to adding 95mg of fertilizer enhancer slurry), and add an appropriate amount of tap water until the water content in the dry soil is 18±2%, thus obtaining experimental group A4.

[0061] Weigh 1000g of dry soil, add urea solution to it until the pure nitrogen content is 120mg, add an appropriate amount of tap water until the water content in the dry soil is 18±2%, and obtain blank group B1.

[0062] A1, A2, A4, and B1 were cultured in an open environment at 35% RH and 23±5℃, while A3 was cultured in an open environment at 35% RH and 38±1℃. Appropriate water was added daily to maintain a stable water content in the dry soil. In addition, A1 and A2 required a stable pH, and A3 required a stable temperature.

[0063] On day 28 of cultivation, equal masses of samples were taken and dissolved in 2M KCl solution to determine the NH4+ content in the extract. + -N content, to obtain A1 NH4 + -N content, denoted as N A1 Similarly, let's denote it as N. A2 N A3 N A4 N B1 The inhibition effect S is then calculated. Taking A1 as an example, S A1 =(NA1 -N B1 ) / N B1 Similarly, we can obtain S A2 S A3 S A4 .

[0064] The operation methods for other embodiments and comparative examples are the same as above, and the specific inhibition effect data are shown in Table 1.

[0065] Table 1. Test data on inhibition effect

[0066] From Table 1 S A1 S A2 S A3 and S A4 It can be seen that after 28 days, the ammonium nitrogen in Examples 1-3 was basically unaffected by urease and nitrifying bacteria in the dry soil, and the active components in the fertilizer synergist remained stable in acidic and alkaline environments (S). A1 S A2 ), temperature (S) A3 The environment can effectively play its role, and the various components in the fertilizer synergist have excellent compatibility (S). A4 ).

Claims

1. A fertilizer synergist that promotes absorption, characterized in that, It is prepared by means of the following components in parts by weight: 0.3-2.5 parts dicyandiamide, 1-1.5 parts potassium humate, 2.5-4.5 parts phytic acid, 3.5-6 parts N-butylthiophosphoric triamine, 1-3 parts magnesium sulfate, 1-3 parts ferric ammonium sulfate, 3.5-5.5 parts animal hair, 5-6 parts bagasse, 2.5-6 parts polyvinyl alcohol, 1.5-3 parts γ-polyglutamic acid, 0.6-0.9 parts glyceryl monostearate, 0.02-0.1 parts vitamin B, 0.08-0.2 parts disodium ethylenediaminetetraacetate, and 85-95 parts water.

2. A method for preparing the fertilizer synergist for promoting absorption as described in claim 1, characterized in that, Includes the following steps: S1. Animal hair, after pretreatment, is added to an alkaline system along with a reducing agent and then heated. S2. Continue to add grafting reagent, catalyst, dicyandiamide, polyvinyl alcohol, γ-polyglutamic acid, glyceryl monostearate and a portion of water, shear emulsify, and then carry out grafting reaction to obtain coating solution; S3. Potassium humate, phytic acid, N-butylthiophosphoric triamine, magnesium sulfate, ferric ammonium sulfate, bagasse, vitamin B, disodium ethylenediaminetetraacetate, and the remaining water are added to the coating solution in batches to obtain the fertilizer synergist.

3. The method for preparing the fertilizer synergist that promotes absorption according to claim 2, characterized in that, In S1, the pretreatment involves cutting the animal hair into small pieces and soaking it in an aqueous sodium hydroxide solution with a sodium hydroxide mass fraction of 2-5 wt% and a mass ratio of animal hair to sodium hydroxide solution of 5:(12-16). The soaking time is 20-24 hours.

4. The method for preparing the fertilizer synergist that promotes absorption according to claim 2, characterized in that, In S1, the reducing agent is sodium thiosulfate, the alkaline system is an aqueous solution of sodium hydroxide, and the mass fraction of sodium hydroxide is 12~18wt%; the mass ratio of animal hair, reducing agent and alkaline system is 5:(0.28~0.4):(6~8).

5. The method for preparing the fertilizer synergist that promotes absorption according to claim 2, characterized in that, In S1, the heat treatment temperature is 75~85℃ and the heat treatment time is 1.5~2h.

6. The method for preparing the fertilizer synergist that promotes absorption according to claim 2, characterized in that, In S2, the grafting agent is 1,4-butanediol diglycidyl ether, and the catalyst is triethanolamine.

7. The method for preparing the fertilizer synergist that promotes absorption according to claim 2, characterized in that, The mass ratio of animal hair, grafting reagent, and catalyst is 5:(0.45~0.55):(0.1~0.16).

8. The method for preparing the fertilizer synergist that promotes absorption according to claim 2, characterized in that, In S2, the mass of water is 2 to 3.5 times the sum of the masses of dicyandiamide, polyvinyl alcohol, γ-polyglutamic acid, and glyceryl monostearate; the shear emulsification rate is 120 to 180 r / min, and the shear emulsification time is 20 to 40 min.

9. The method for preparing the fertilizer synergist that promotes absorption according to claim 2, characterized in that, In S2, the grafting reaction temperature is 55~65℃ and the grafting reaction time is 3~5h.

10. The method for preparing the fertilizer synergist for promoting absorption according to claim 2, characterized in that, In S3, the number of batches is 8 to 12. After all batches are added, continue stirring for 10 to 20 minutes.

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