Efficient preparation method and simple system of amino acid-containing water-soluble fertilizer

Abstract

The invention relates to the technical field of water-soluble fertilizers, in particular to an efficient preparation method of a water-soluble fertilizer containing amino acid and a simple system.The efficient preparation method comprises the following steps that raw material pretreatment is conducted, specifically, soybean meal or animal fur is selected as a raw material, and smashing and homogenizing treatment are conducted; the pretreated raw materials are put into an enzymolysis tank, the temperature is controlled to be 45-50 DEG C, the pH value is 6.5-7.0, the stirring speed is 150 rpm, and enzymolysis is conducted till the hydrolysis degree reaches 25% or above. According to the efficient preparation method of the amino acid-containing water-soluble fertilizer, the modified additive and the chelation optimization strategy, the core is to provide a solution aiming at four major pain points of'unstable hydrolysis, low purity, poor chelation and high cost 'in the prior art, and meanwhile, a matched simple system reduces the application threshold.

Description

Technical Field

[0001] This invention relates to the field of water-soluble fertilizer technology, specifically to a highly efficient preparation method and simple system for amino acid-containing water-soluble fertilizers. Background Technology

[0002] Amino acid-containing water-soluble fertilizers are widely used in agricultural production because they can provide crops with high-quality nitrogen sources and various nutrients. Currently, the mainstream preparation process uses enzyme-microbial synergistic hydrolysis of raw materials such as soybean meal and animal hides, but this process has significant technical bottlenecks.

[0003] First, batch-to-batch variations in raw materials lead to instability in the degree of hydrolysis. The protein content and fiber structure of raw materials such as soybean meal and animal hides vary depending on the place of origin and processing method. Existing processes use fixed enzymatic hydrolysis and fermentation parameters, which cannot be adapted to changes in raw materials. This results in significant fluctuations in the yield of free amino acids between different batches of products, affecting the consistency of product quality.

[0004] Secondly, low product purity restricts crop absorption. Existing processes mostly use a single filtration method to separate impurities, which makes it difficult to remove large-particle raw material residues and fine impurities such as microbial proteins at the same time. The residue of impurities leads to insufficient product purity, reducing the crop's absorption efficiency of amino acids and trace elements.

[0005] Furthermore, the chelation effect of trace elements is poor. During the chelation process, the ratio of trace elements to amino acids relies on manual adjustment, which easily leads to imbalance, resulting in incomplete chelation and precipitation. If sugar alcohols are added to improve the chelation effect, the existing process still suffers from low chelation rate and easy precipitation during product storage because it does not design suitable sugar alcohol ratios for different elements and relies on experience to control reaction conditions. In addition, offline detection of chelation rate results in lag in feedback, often causing raw material waste and increasing production costs. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the purpose of this invention is to provide an efficient preparation method and simple system for amino acid-containing water-soluble fertilizers, so as to solve the problems mentioned in the background art.

[0007] The present invention solves the technical problem by adopting the following technical solution: This invention provides a highly efficient method for preparing amino acid-containing water-soluble fertilizers, comprising the following steps: Step 1, Raw material pretreatment: Select soybean meal or animal hides as raw materials and perform crushing and homogenization. Step 2: Put the pretreated raw materials into the enzymatic hydrolysis tank, control the temperature at 45-50℃, the pH value at 6.5-7.0, and the stirring speed at 150rpm, and carry out enzymatic hydrolysis until the degree of hydrolysis reaches more than 25%. Microbial fermentation stage: After enzymatic hydrolysis, switch the parameters to inoculum size of 6%-8%, temperature of 35℃, and pH value of 6.8-7.2, and carry out fermentation until the concentration of free amino acids in the fermentation broth is ≥120g / L; Step 3, two-stage purification: First, filter through a 1μm filter cartridge to remove large particulate impurities, and then filter through a 0.45μm membrane to remove bacterial protein impurities; Step 4, chelation reaction: The purified amino acid solution is sent into the chelation tank, and trace elements are added at a mass ratio of 1:(5-8) of trace elements to amino acid solution. The temperature is controlled at 40-45℃ and the reaction is stirred for 30-35 minutes. After natural cooling, water-soluble fertilizer containing amino acids is obtained.

[0008] Preferably, the trace elements are calcium and magnesium in a weight ratio of 2:1; the microbial fermentation strains are Bacillus subtilis or yeast.

[0009] Preferably, a modifying additive of 15-20% of the total amount of amino acid solution is added during the chelation reaction. The method for preparing the modifying additive is as follows: S01: Preheat kaolin at 55-60℃ for 1 hour to obtain preheated kaolin. Stir the preheated kaolin and sodium dodecylbenzenesulfonate solution at a weight ratio of 3:(5-8) to obtain kaolin liquid. S02: Graphene modifier, carbon nanotube agent and kaolin liquid are mixed and ball-milled in a weight ratio of (5-8):(3-5):3. The ball milling speed is 1000-1500 r / min and the ball milling time is 2h. After the ball milling is completed, the mixture is filtered and dried to obtain the modified additive.

[0010] Preferably, the preparation method of the carbon nanotube agent is as follows: Carbon nanotubes were heat-treated at 135-145℃ for 1 hour. The heat-treated carbon nanotubes and the treatment solution were ultrasonically treated at a weight ratio of 5:(8-11). After the treatment was completed, the mixture was filtered and dried to obtain carbon nanotube agent. The treatment solution comprises the following raw materials in parts by weight: 2-5 parts of lanthanum nitrate solution, 1-3 parts of titanium dioxide, 2-4 parts of attapulgite, and 2-3 parts of sodium silicate solution are thoroughly mixed to obtain a treatment solution; the mass fraction of the lanthanum nitrate solution is 2-5%; and the mass fraction of the sodium silicate solution is 8-12%.

[0011] Preferably, the ultrasonic power for ultrasonic treatment is 350-400W, and the ultrasonic treatment lasts for 20-30 minutes.

[0012] Preferably, the preparation method of the graphene modifier is as follows: Graphene is stirred thoroughly in a sodium citrate solution at 3-5 times its total weight to obtain a graphene solution. 3-5 parts basalt fiber, 2-5 parts boron nitride, and 4-7 parts β-cyclodextrin are added to 10-15 parts of the graphene solution for co-processing. After processing, the mixture is filtered and dried to obtain a graphene modifier.

[0013] Preferably, the sodium citrate solution has a mass fraction of 10-15%; the mixing speed is 350-450 r / min, and the mixing time is 1 h.

[0014] Preferably, the β-cyclodextrin agent is a complex of β-cyclodextrin, silane coupling agent KH550, and an aqueous ethanol solution.

[0015] Preferably, the mass fraction of the ethanol aqueous solution is 75-85%; the mass ratio of β-cyclodextrin, silane coupling agent KH550 and ethanol aqueous solution is (3-6):2:(5-8).

[0016] The present invention also provides a simple system for implementing the method, comprising a raw material pretreatment unit, an enzymatic hydrolysis tank, a fermentation tank, a two-stage filtration assembly, and a chelation tank connected in sequence; the enzymatic hydrolysis tank, the fermentation tank, and the chelation tank are all equipped with a temperature sensor, a pH sensor, and a stirring device; the two-stage filtration assembly includes a 1μm cartridge filter and a 0.45μm membrane filter connected in sequence; the chelation tank is connected to a metering pump for precise addition of trace element raw materials.

[0017] A method for chelating and optimizing amino acid-containing water-soluble fertilizers with added sugar alcohols includes the following steps: Preparation of free amino acid solution: The enzymatic hydrolysis, fermentation and purification steps described in the claims are used until the concentration of free amino acids in the fermentation broth is ≥120g / L; Sugar alcohol and trace element ratio: Add sugar alcohol in the following mass ratios for different elements: calcium to sugar alcohol 1:2-3, iron to sugar alcohol 1:1.5-2, magnesium to sugar alcohol 1:2.5-3; Chelation reaction control: Add amino acid solution, trace elements and sugar alcohol into a stirred tank with temperature control and timing function, control the temperature at 35-40℃, the stirring speed at 200rpm, and the reaction time at 40-60min. Rapid detection and replenishment: After 30 minutes of reaction, the chelation rate is detected using a portable colorimetric reagent. If the chelation rate is <90%, the corresponding proportion of sugar alcohol is added, and the reaction continues for 10 minutes until the chelation rate is ≥90%. The mixture is then allowed to cool naturally to room temperature. The sugar alcohol is sorbitol or mannitol.

[0018] Compared with the prior art, the present invention has the following beneficial effects: This invention presents a highly efficient preparation method for amino acid-containing water-soluble fertilizer, along with modified additives and chelation optimization strategies. The core of this method addresses four major pain points of existing processes: unstable hydrolysis, low purity, poor chelation, and high cost. It also includes a simplified system to lower the application threshold, pretreatment homogenization to reduce raw material variations: through "pulverization + homogenization," the uneven particle size and fiber structure of the raw materials are eliminated, ensuring consistent contact area between the raw materials and enzymes during subsequent enzymatic hydrolysis, thus reducing the impact of batch variations on hydrolysis from the source. Precise locking of enzymatic hydrolysis-fermentation parameters ensures hydrolysis efficiency: this method achieves deep impurity removal through two-stage step filtration. With reduced impurities, crop roots can competitively absorb amino acids and trace elements. It reduces root absorption obstacles caused by impurities, especially for fruit and vegetable crops (such as tomatoes and strawberries); basic chelation: precise ratio of micronutrients to reduce precipitation; fixed weight ratio of micronutrients (calcium and magnesium) of 2:1, adapted to the carboxyl and amino binding sites of amino acids, avoiding incomplete chelation caused by excessive single element (such as excessive calcium easily forming calcium carbonate precipitate with carbonate ions); modified additives enhance chelation stability and assist in slow release of nutrients. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to specific examples. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] The efficient preparation method of amino acid-containing water-soluble fertilizer in this embodiment includes the following steps: Step 1, Raw material pretreatment: Select soybean meal or animal hides as raw materials and perform crushing and homogenization. Step 2: Put the pretreated raw materials into the enzymatic hydrolysis tank, control the temperature at 45-50℃, the pH value at 6.5-7.0, and the stirring speed at 150rpm, and carry out enzymatic hydrolysis until the degree of hydrolysis reaches more than 25%. Microbial fermentation stage: After enzymatic hydrolysis, switch the parameters to inoculum size of 6%-8%, temperature of 35℃, and pH value of 6.8-7.2, and carry out fermentation until the concentration of free amino acids in the fermentation broth is ≥120g / L; Step 3, two-stage purification: First, filter through a 1μm filter cartridge to remove large particulate impurities, and then filter through a 0.45μm membrane to remove bacterial protein impurities; Step 4, chelation reaction: The purified amino acid solution is sent into the chelation tank, and trace elements are added at a mass ratio of 1:(5-8) of trace elements to amino acid solution. The temperature is controlled at 40-45℃ and the reaction is stirred for 30-35 minutes. After natural cooling, water-soluble fertilizer containing amino acids is obtained.

[0021] In this embodiment, the trace elements are calcium and magnesium in a weight ratio of 2:1; the microbial fermentation stage uses Bacillus subtilis or yeast.

[0022] In this embodiment, a modifying additive of 15-20% of the total amount of amino acid solution is added to the chelation reaction. The preparation method of the modifying additive is as follows: S01: Preheat kaolin at 55-60℃ for 1 hour to obtain preheated kaolin. Stir the preheated kaolin and sodium dodecylbenzenesulfonate solution at a weight ratio of 3:(5-8) to obtain kaolin liquid. S02: Graphene modifier, carbon nanotube agent and kaolin liquid are mixed and ball-milled in a weight ratio of (5-8):(3-5):3. The ball milling speed is 1000-1500 r / min and the ball milling time is 2h. After the ball milling is completed, the mixture is filtered and dried to obtain the modified additive.

[0023] The preparation method of the carbon nanotube agent in this embodiment is as follows: Carbon nanotubes were heat-treated at 135-145℃ for 1 hour. The heat-treated carbon nanotubes and the treatment solution were ultrasonically treated at a weight ratio of 5:(8-11). After the treatment was completed, the mixture was filtered and dried to obtain carbon nanotube agent. The treatment solution comprises the following raw materials in parts by weight: 2-5 parts of lanthanum nitrate solution, 1-3 parts of titanium dioxide, 2-4 parts of attapulgite, and 2-3 parts of sodium silicate solution are thoroughly mixed to obtain a treatment solution; the mass fraction of the lanthanum nitrate solution is 2-5%; and the mass fraction of the sodium silicate solution is 8-12%.

[0024] In this embodiment, the ultrasonic power for ultrasonic treatment is 350-400W, and the ultrasonic treatment lasts for 20-30 minutes.

[0025] The preparation method of the graphene modifier in this embodiment is as follows: Graphene is stirred thoroughly in a sodium citrate solution at 3-5 times its total weight to obtain a graphene solution. 3-5 parts basalt fiber, 2-5 parts boron nitride, and 4-7 parts β-cyclodextrin are added to 10-15 parts of the graphene solution for co-processing. After processing, the mixture is filtered and dried to obtain a graphene modifier.

[0026] In this embodiment, the sodium citrate solution has a mass fraction of 10-15%; the mixing speed is 350-450 r / min, and the mixing time is 1 h.

[0027] The β-cyclodextrin agent in this embodiment is a complex of β-cyclodextrin, silane coupling agent KH550, and an aqueous ethanol solution.

[0028] In this embodiment, the mass fraction of the ethanol aqueous solution is 75-85%; the mass ratio of β-cyclodextrin, silane coupling agent KH550 and ethanol aqueous solution is (3-6):2:(5-8).

[0029] A simplified system for implementing the method according to this embodiment includes a raw material pretreatment unit, an enzymatic hydrolysis tank, a fermentation tank, a two-stage filtration assembly, and a chelation tank connected in sequence. The enzymatic hydrolysis tank, fermentation tank, and chelation tank are all equipped with a temperature sensor, a pH sensor, and a stirring device. The two-stage filtration assembly includes a 1μm cartridge filter and a 0.45μm membrane filter connected in sequence. The chelation tank is connected to a metering pump for precise addition of trace element raw materials.

[0030] This embodiment of a method for chelating and optimizing amino acid-containing water-soluble fertilizer with added sugar alcohols includes the following steps: Preparation of free amino acid solution: The enzymatic hydrolysis, fermentation and purification steps described in the claims are adopted, and the concentration of free amino acids in the fermentation broth is ≥120g / L; Sugar alcohol and trace element ratio: Add sugar alcohol in the following mass ratios for different elements: calcium to sugar alcohol 1:2-3, iron to sugar alcohol 1:1.5-2, magnesium to sugar alcohol 1:2.5-3; Chelation reaction control: Add amino acid solution, trace elements and sugar alcohol into a stirred tank with temperature control and timing function, control the temperature at 35-40℃, the stirring speed at 200rpm, and the reaction time at 40-60min. Rapid detection and replenishment: After 30 minutes of reaction, the chelation rate is detected using a portable colorimetric reagent. If the chelation rate is <90%, the corresponding proportion of sugar alcohol is added, and the reaction continues for 10 minutes until the chelation rate is ≥90%. The mixture is then allowed to cool naturally to room temperature. The sugar alcohol is sorbitol or mannitol.

[0031] Example 1: Preparation of water-soluble fertilizer containing amino acids (using soybean meal as raw material) Raw material pretreatment: Take 10 kg of soybean meal, grind it to 80 mesh, add 50 L of water and homogenize to obtain raw material slurry.

[0032] Enzymatic hydrolysis stage: The raw material slurry is fed into an enzymatic hydrolysis tank, and protease is added (0.5% of the raw material mass). The temperature is controlled at 48℃, the pH value at 6.8, and the stirring speed at 150 rpm. Enzymatic hydrolysis is carried out for 4 hours, and the degree of hydrolysis is measured to reach 28%.

[0033] Microbial fermentation stage: 7% Bacillus subtilis was inoculated into the enzymatic hydrolysate, the temperature was controlled at 35℃ and the pH value at 7.0, and fermentation was carried out for 6 hours. The concentration of free amino acids was measured to be 130g / L.

[0034] Two-stage purification: First, the mixture is filtered through a 1μm filter cartridge to remove soybean meal residue; then, it is filtered through a 0.45μm filter membrane to remove bacterial protein, resulting in a purified amino acid solution.

[0035] Chelation reaction: The purified amino acid solution was fed into a chelation tank, and zinc element was added at a mass ratio of 1:6 (50L amino acid solution, 5kg zinc element). The temperature was controlled at 40℃, and the mixture was stirred for 30 minutes. After natural cooling, a water-soluble fertilizer containing amino acids was obtained. Testing showed that the yield of free amino acids in the product was 12% higher than that of the traditional process, with a purity of 96% and a zinc chelation rate of 88%.

[0036] Example 2: Preparation of Amino Acid-Containing Water-Soluble Fertilizer with Added Sugar Alcohol Preparation of free amino acid solution: 50 L of purified amino acid solution was obtained by using the method in Example 1.

[0037] Raw material ratio: The ratio of calcium to sorbitol is 1:2.5 and the ratio of iron to sorbitol is 1:1.8. The raw materials are 3 kg of calcium, 2 kg of iron and 11.1 kg of sorbitol.

[0038] Chelation reaction: Add amino acid solution, calcium, iron and sorbitol into a stirred tank, control the temperature at 38℃ and the stirring speed at 200 rpm, and react for 50 min.

[0039] Rapid testing and replenishment: Samples were taken after 30 minutes of reaction and tested with a portable colorimetric reagent; the chelation rate was 86%. 0.5 kg of sorbitol was added, and the reaction continued for another 10 minutes; the chelation rate was then tested again and found to be 92%. The product was then allowed to cool naturally to room temperature. Testing showed that the product showed no precipitation after 10 months of storage, and the absorption and utilization rate of calcium and iron by crops was increased by 25% compared to traditional processes.

[0040] Optimization Example 1. Based on Example 1, a modifying additive of 15% of the total amount of amino acid solution was added to the chelation reaction. The preparation method of the modifying additive is as follows: S01: Preheat kaolin at 55℃ for 1 hour to obtain preheated kaolin. Stir the preheated kaolin and sodium dodecylbenzenesulfonate solution at a weight ratio of 3:5 to obtain kaolin liquid. S02: Graphene modifier, carbon nanotube agent and kaolin liquid were mixed and ball-milled in a weight ratio of 5:3:3 at a speed of 1000 r / min for 2 hours. After ball milling, the mixture was filtered and dried to obtain the modified additive.

[0041] The preparation method of the carbon nanotube agent in this embodiment is as follows: Carbon nanotubes were heat-treated at 135℃ for 1 hour. The heat-treated carbon nanotubes and the treatment solution were ultrasonically treated at a weight ratio of 5:8. After the treatment was completed, the mixture was filtered and dried to obtain the carbon nanotube agent. The treatment solution comprises the following raw materials in parts by weight: Two parts of lanthanum nitrate solution, one part of titanium dioxide, two parts of attapulgite, and two parts of sodium silicate solution were thoroughly mixed to obtain a treatment solution; the mass fraction of the lanthanum nitrate solution was 2%; and the mass fraction of the sodium silicate solution was 8%.

[0042] In this embodiment, the ultrasonic power for ultrasonic treatment is 350W, and the ultrasonic treatment lasts for 20 minutes.

[0043] The preparation method of the graphene modifier in this embodiment is as follows: Graphene was stirred thoroughly in a sodium citrate solution with a total volume of 3 times the graphene to obtain a graphene solution. 3 parts basalt fiber, 2 parts boron nitride and 4 parts β-cyclodextrin were added to 10 parts of the graphene solution for co-processing. After the processing was completed, the solution was filtered and dried to obtain a graphene modifier.

[0044] In this embodiment, the sodium citrate solution has a mass fraction of 10%; the mixing speed is 350 r / min, and the mixing time is 1 h.

[0045] The β-cyclodextrin agent in this embodiment is a complex of β-cyclodextrin, silane coupling agent KH550, and an aqueous ethanol solution.

[0046] In this embodiment, the mass fraction of the ethanol aqueous solution is 75%; the mass ratio of β-cyclodextrin, silane coupling agent KH550 and ethanol aqueous solution is 3:2:5.

[0047] Optimization Example 2. Based on Example 1, a modifying additive of 20% of the total amount of amino acid solution was added to the chelation reaction. The preparation method of the modifying additive is as follows: S01: Preheat kaolin at 60℃ for 1 hour to obtain preheated kaolin. Stir the preheated kaolin and sodium dodecylbenzenesulfonate solution at a weight ratio of 3:8 to obtain kaolin liquid. S02: Graphene modifier, carbon nanotube agent and kaolin liquid were mixed and ball-milled at a weight ratio of 8:5:3 for 2 hours at a speed of 1500 r / min. After ball milling, the mixture was filtered and dried to obtain the modified additive.

[0048] The preparation method of the carbon nanotube agent in this embodiment is as follows: Carbon nanotubes were heat-treated at 145℃ for 1 hour. The heat-treated carbon nanotubes and the treatment solution were ultrasonically treated at a weight ratio of 5:11. After the treatment was completed, the mixture was filtered and dried to obtain carbon nanotube agent. The treatment solution comprises the following raw materials in parts by weight: Five parts of lanthanum nitrate solution, three parts of titanium dioxide, four parts of attapulgite, and three parts of sodium silicate solution were thoroughly mixed to obtain a treatment solution; the mass fraction of the lanthanum nitrate solution was 5%; and the mass fraction of the sodium silicate solution was 12%.

[0049] In this embodiment, the ultrasonic power for ultrasonic treatment is 400W, and the ultrasonic treatment lasts for 30 minutes.

[0050] The preparation method of the graphene modifier in this embodiment is as follows: Graphene was stirred thoroughly in a sodium citrate solution with a volume of 5 times the total amount of graphene to obtain a graphene solution. 5 parts of basalt fiber, 5 parts of boron nitride, and 7 parts of β-cyclodextrin were added to 15 parts of the graphene solution for co-processing. After processing, the solution was filtered and dried to obtain a graphene modifier.

[0051] In this embodiment, the sodium citrate solution has a mass fraction of 15%; the mixing speed is 450 r / min, and the mixing time is 1 h.

[0052] The β-cyclodextrin agent in this embodiment is a complex of β-cyclodextrin, silane coupling agent KH550, and an aqueous ethanol solution.

[0053] In this embodiment, the mass fraction of the ethanol aqueous solution is 85%; the mass ratio of β-cyclodextrin, silane coupling agent KH550 and ethanol aqueous solution is 6:2:8.

[0054] Optimization example 3. Based on Example 1, a modifying additive of 17.5% of the total amino acid solution was added to the chelation reaction. The preparation method of the modifying additive is as follows: S01: Preheat kaolin at 58℃ for 1 hour to obtain preheated kaolin. Stir the preheated kaolin and sodium dodecylbenzenesulfonate solution at a weight ratio of 3:6.5 to obtain kaolin liquid. S02: Graphene modifier, carbon nanotube agent and kaolin liquid were mixed and ball-milled at a weight ratio of 6.5:4:3 for 2 hours at a speed of 1250 r / min. After ball milling, the mixture was filtered and dried to obtain the modified additive.

[0055] The preparation method of the carbon nanotube agent in this embodiment is as follows: Carbon nanotubes were heat-treated at 140℃ for 1 hour. The heat-treated carbon nanotubes and the treatment solution were ultrasonically treated at a weight ratio of 5:9. After the treatment was completed, the mixture was filtered and dried to obtain carbon nanotube agent. The treatment solution comprises the following raw materials in parts by weight: 3.5 parts lanthanum nitrate solution, 2 parts titanium dioxide, 3 parts attapulgite, and 2.5 parts sodium silicate solution were thoroughly mixed to obtain a treatment solution; the mass fraction of the lanthanum nitrate solution was 3.5%; and the mass fraction of the sodium silicate solution was 10%.

[0056] In this embodiment, the ultrasonic power for ultrasonic treatment is 370W, and the ultrasonic treatment lasts for 25 minutes.

[0057] The preparation method of the graphene modifier in this embodiment is as follows: Graphene was stirred thoroughly in a sodium citrate solution with a total volume of 4 times the amount of graphene to obtain a graphene solution. 4 parts of basalt fiber, 3.5 parts of boron nitride, and 5.5 parts of β-cyclodextrin were added to 12.5 parts of the graphene solution for co-processing. After processing, the solution was filtered and dried to obtain a graphene modifier.

[0058] In this embodiment, the sodium citrate solution has a mass fraction of 12.5%; the mixing speed is 400 r / min, and the mixing time is 1 h.

[0059] The β-cyclodextrin agent in this embodiment is a complex of β-cyclodextrin, silane coupling agent KH550, and an aqueous ethanol solution.

[0060] In this embodiment, the mass fraction of the ethanol aqueous solution is 80%; the mass ratio of β-cyclodextrin, silane coupling agent KH550 and ethanol aqueous solution is 4.5:2:6.5.

[0061] Comparative Example 1. Unlike Example 3, which is an optimized example, no carbon nanotube agent was added.

[0062] Comparative Example 2. Unlike Example 3, no treatment solution was added during the preparation of the carbon nanotube agent.

[0063] Comparative Example 3. Unlike Example 3, titanium dioxide and attapulgite were not added to the treatment solution.

[0064] Comparative Example 4. Unlike Example 3, no graphene modifier was added.

[0065] Comparative Example 5. Unlike Example 3, β-cyclodextrin was not added in the preparation of the graphene modifier.

[0066] Comparative Example 6. Unlike Example 3, basalt fibers and boron nitride were not added in the preparation of the graphene modifier.

[0067] Performance tests of Optimized Examples 1-3 and Comparative Examples 1-6 were conducted using wheat (winter wheat variety "Jimai 44") as the test subject. A combination of root irrigation and foliar spraying was used (one root irrigation during the seedling stage, and one foliar spray each during the jointing and grain-filling stages, diluted 500 times). The test results are as follows:

[0068] From Examples 1-3 and Comparative Examples 1-6, it can be seen that the product of the present invention can achieve coordinated improvement in yield per acre, incidence of sheath blight, and thousand-grain weight. The product does not contain carbon nanotube agent, the carbon nanotube agent does not contain treatment liquid, the treatment liquid does not contain titanium dioxide and attapulgite, the graphene modifier does not contain graphene modifier, the graphene modifier does not contain β-cyclodextrin agent, the graphene modifier does not contain basalt fiber and boron nitride. The performance of the product tends to deteriorate. Only the product raw materials obtained by the method of the present invention have the most significant performance effect.

[0069] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0070] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A highly efficient method for preparing amino acid-containing water-soluble fertilizer, characterized in that, Includes the following steps: Step 1, Raw material pretreatment: Select soybean meal or animal hides as raw materials and perform crushing and homogenization. Step 2: Put the pretreated raw materials into the enzymatic hydrolysis tank, control the temperature at 45-50℃, the pH value at 6.5-7.0, and the stirring speed at 150rpm, and carry out enzymatic hydrolysis until the degree of hydrolysis reaches more than 25%. Microbial fermentation stage: After enzymatic hydrolysis, switch the parameters to inoculum size of 6%-8%, temperature of 35℃, and pH value of 6.8-7.2, and carry out fermentation until the concentration of free amino acids in the fermentation broth is ≥120g / L; Step 3, two-stage purification: First, filter through a 1μm filter cartridge to remove large particulate impurities, and then filter through a 0.45μm membrane to remove bacterial protein impurities; Step 4, chelation reaction: The purified amino acid solution is sent into the chelation tank, and trace elements are added at a mass ratio of 1:(5-8) of trace elements to amino acid solution. The temperature is controlled at 40-45℃ and the reaction is stirred for 30-35 minutes. After natural cooling, water-soluble fertilizer containing amino acids is obtained.

2. The method for efficiently preparing amino acid-containing water-soluble fertilizer according to claim 1, characterized in that, The trace elements are calcium and magnesium in a weight ratio of 2:1; the microbial fermentation stage uses Bacillus subtilis or yeast.

3. The method for efficiently preparing amino acid-containing water-soluble fertilizer according to claim 1, characterized in that, The chelation reaction also involves adding a modifying additive at 15-20% of the total amount of amino acid solution. The preparation method of the modifying additive is as follows: S01: Preheat kaolin at 55-60℃ for 1 hour to obtain preheated kaolin. Stir the preheated kaolin and sodium dodecylbenzenesulfonate solution at a weight ratio of 3:(5-8) to obtain kaolin liquid. S02: Graphene modifier, carbon nanotube agent and kaolin liquid are mixed and ball-milled in a weight ratio of (5-8):(3-5):

3. The ball milling speed is 1000-1500 r / min and the ball milling time is 2h. After the ball milling is completed, the mixture is filtered and dried to obtain the modified additive.

4. The method for efficiently preparing amino acid-containing water-soluble fertilizer according to claim 3, characterized in that, The preparation method of carbon nanotube agent is as follows: Carbon nanotubes were heat-treated at 135-145℃ for 1 hour. The heat-treated carbon nanotubes and the treatment solution were ultrasonically treated at a weight ratio of 5:(8-11). After the treatment was completed, the mixture was filtered and dried to obtain carbon nanotube agent. The treatment solution comprises the following raw materials in parts by weight: 2-5 parts of lanthanum nitrate solution, 1-3 parts of titanium dioxide, 2-4 parts of attapulgite, and 2-3 parts of sodium silicate solution are thoroughly mixed to obtain a treatment solution; the mass fraction of the lanthanum nitrate solution is 2-5%; and the mass fraction of the sodium silicate solution is 8-12%.

5. The method for efficiently preparing amino acid-containing water-soluble fertilizer according to claim 4, characterized in that, The ultrasonic power for ultrasonic treatment is 350-400W, and the ultrasonic treatment lasts for 20-30 minutes.

6. The method for efficiently preparing amino acid-containing water-soluble fertilizer according to claim 4, characterized in that, The preparation method of graphene modifier is as follows: Graphene is stirred thoroughly in a sodium citrate solution at 3-5 times its total weight to obtain a graphene solution. 3-5 parts basalt fiber, 2-5 parts boron nitride, and 4-7 parts β-cyclodextrin are added to 10-15 parts of the graphene solution for co-processing. After processing, the mixture is filtered and dried to obtain a graphene modifier.

7. The method for efficiently preparing amino acid-containing water-soluble fertilizer according to claim 6, characterized in that, The sodium citrate solution has a mass fraction of 10-15%; the blending process is carried out at a speed of 350-450 r / min for 1 h.

8. The method for efficiently preparing amino acid-containing water-soluble fertilizer according to claim 6, characterized in that, The β-cyclodextrin agent is a complex of β-cyclodextrin, silane coupling agent KH550, and an aqueous ethanol solution.

9. The method for efficiently preparing amino acid-containing water-soluble fertilizer according to claim 8, characterized in that, The mass fraction of the ethanol aqueous solution is 75-85%; the mass ratio of β-cyclodextrin, silane coupling agent KH550 and ethanol aqueous solution is (3-6):2:(5-8).

10. A simplified system for implementing the method of claim 1, characterized in that, The system includes a raw material pretreatment unit, an enzymatic hydrolysis tank, a fermentation tank, a two-stage filtration assembly, and a chelation tank connected in sequence. Each of the enzymatic hydrolysis tank, fermentation tank, and chelation tank is equipped with a temperature sensor, a pH sensor, and a stirring device. The two-stage filtration assembly includes a 1μm cartridge filter and a 0.45μm membrane filter connected in sequence. The chelation tank is connected to a metering pump for precise addition of trace element raw materials.

Images