Amino acid water-soluble fertilizer and preparation method thereof

Abstract

The invention discloses an amino acid water-soluble fertilizer and a preparation method thereof, and belongs to the technical field of fertilizer preparation. The amino acid water-soluble fertilizer comprises the following raw materials by weight: 10 to 15 parts of composite amino acids, 1 to 3 parts of ferrous sulfate, 2 to 4 parts of copper sulfate, 3 to 5 parts of zinc sulfate, 2 to 3 parts of manganese sulfate, 18 to 20 parts of carboxymethyl chitosan, 3 to 4 parts of potassium sulfate, 10 to 15 parts of potassium dihydrogen phosphate, and 3 to 4 parts of a wetting and dispersing agent. The amino acid water-soluble fertilizer of the present invention can induce crops to produce a large amount of cytokinins and promote chlorophyll synthesis, increase photosynthetic rate and photosynthesis intensity, and thus enhance plant vitality. The wetting and dispersing agent is reasonably added to make the dispersibility and solubility of the fertilizer better; at the same time, it is easier to be absorbed and utilized by plants, thereby helping plants to better absorb nutrients, greatly improving the crop's absorption rate of fertilizers, reducing fertilizer losses, and saving costs.

Description

Technical Field

[0001] The present invention relates to the technical field of fertilizer preparation, in particular to an amino acid water-soluble fertilizer and a preparation method thereof. Background Art

[0002] Amino acids act as accelerators and catalysts for the synthesis of various enzymes in plants, uniquely promoting plant growth, particularly photosynthesis. Amino acid fertilizers can increase the content of various nutrients required by plants, accelerate dry matter accumulation, and regulate the ratio and balance of macronutrients, trace elements, and various nutrients, thereby regulating normal plant growth. Amino acids also act as chelating agents, chelating trace elements such as Zn, Fe, Cu, Mn, B, and Mo, facilitating their absorption and utilization by plants. Amino acids can also increase plant resistance (disease resistance, cold resistance, and winter hardiness), improving plants' ability to withstand adverse environments.

[0003] Water-soluble fertilizer refers to a multi-element, complex, fast-acting fertilizer that can be completely dissolved in water. It has the advantages of controllable formula, high absorption efficiency, economical, convenient and safe application. It can be used for sprinkler irrigation, foliar fertilization, seed soaking and root dipping, and soilless cultivation to achieve water and fertilizer integration, and has great potential especially in facility agricultural production.

[0004] Amino acid water-soluble fertilizers are liquid or solid water-soluble fertilizers made primarily of free amino acids, with appropriate amounts of copper, iron, manganese, zinc, boron, molybdenum, and other trace elements or calcium added in proportions suitable for plant growth. These fertilizers offer advantages such as high targeting, rapid efficacy, minimal fertilizer usage, labor savings, and significant yield increases. However, their effectiveness is short-lived and requires regular application, resulting in high costs. Summary of the Invention

[0005] The purpose of the present invention is to provide an amino acid water-soluble fertilizer and a preparation method thereof, so as to solve the problems existing in the above-mentioned prior art.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] One of the technical solutions of the present invention is an amino acid water-soluble fertilizer, which comprises the following raw materials in parts by mass: 10-15 parts of complex amino acids, 1-3 parts of ferrous sulfate, 2-4 parts of copper sulfate, 3-5 parts of zinc sulfate, 2-3 parts of manganese sulfate, 18-20 parts of carboxymethyl chitosan, 3-4 parts of potassium sulfate, 10-15 parts of potassium dihydrogen phosphate and 3-4 parts of a wetting and dispersing agent.

[0008] Furthermore, the preparation of the composite amino acid specifically includes:

[0009] A. Crush the crop straw and add it to a hydrochloric acid solution, heat it, and then dropwise add an ammonium bicarbonate solution to neutralize it to a pH of 6-8 to obtain a composite amino acid aqueous solution;

[0010] B. placing the composite amino acid aqueous solution in a drying oven and drying it at low temperature to obtain the composite amino acid.

[0011] Furthermore, in step A, the mass concentration of the hydrochloric acid solution is 23-25%; and the temperature of the heating treatment is 80-90°C.

[0012] Furthermore, in step A, the powder is crushed to a particle size of 0.1 to 0.5 mm.

[0013] Furthermore, the wetting and dispersing agent is sodium salt or potassium salt of dodecylbenzenesulfonic acid; and the molecular weight of the carboxymethyl chitosan is 8500-9500.

[0014] The second technical solution of the present invention is a method for preparing the above-mentioned amino acid water-soluble fertilizer, comprising the following steps:

[0015] (1) Weighing each raw material according to mass fraction, dissolving the composite amino acid in water to obtain a composite amino acid solution;

[0016] (2) dissolving carboxymethyl chitosan in water, adjusting the pH value to acidic, then adding the composite amino acid solution, stirring and dispersing uniformly, adding a polyphosphate solution dropwise, stirring and reacting, centrifuging, and drying to obtain composite amino acid nanoparticles;

[0017] (3) dispersing the composite amino acid nanoparticles in water, then adding a wetting dispersant, stirring and dispersing them uniformly, and finally adding ferrous sulfate, copper sulfate, zinc sulfate, manganese sulfate, potassium sulfate, and potassium dihydrogen phosphate, mixing and dissolving them to obtain the amino acid water-soluble fertilizer.

[0018] Furthermore, in step (2), the pH value is 3-4.

[0019] Furthermore, in step (2), the concentration of the polyphosphate solution is 24 to 30 g / L.

[0020] Furthermore, in step (2), the mass ratio of polyphosphate to carboxymethyl chitosan in the polyphosphate solution is 1:(7-8).

[0021] Furthermore, in step (2), the stirring reaction time is 2 to 3 hours.

[0022] Amino acid water-soluble fertilizers have a short effective period and need to be sprayed regularly. Therefore, there will be problems of fertilizer loss and high fertilization costs. However, by using carboxymethyl chitosan with good water solubility to prepare nano-slow-release particles and encapsulating complex amino acids in carboxymethyl chitosan nanoparticles, the complex amino acids can be released slowly, reducing the volatilization and leaching losses of the complex amino acids, and improving the absorption and utilization rate and effective period of the complex amino acids, which can achieve the purpose of reducing the number of fertilizations and reducing the cost of fertilization.

[0023] The amino acids continuously released from amino acid water-soluble fertilizers can chelate the metal elements in ferrous sulfate, copper sulfate, zinc sulfate, and manganese sulfate, carry the metal elements into the plant body, and continuously provide trace elements for the plant. This can not only meet the long-term nutritional supply of the plant, but also avoid the phenomenon of excessive accumulation of trace elements in the plant body, and achieve a balanced state of various nutrients.

[0024] The present invention discloses the following technical effects:

[0025] (1) The amino acid water-soluble fertilizer of the present invention contains rich amino acids and trace elements. After being applied to crops, it can improve the stress resistance and yield of crops.

[0026] (2) In the process of preparing composite amino acid nanoparticles, the present invention adopts an ionic crosslinking method, which does not require the addition of external chemical crosslinking agents and is environmentally friendly.

[0027] (3) The amino acid water-soluble fertilizer of the present invention can induce crops to produce a large amount of cytokinins and promote chlorophyll synthesis, thereby increasing photosynthetic rate and photosynthesis intensity, thereby enhancing plant vitality. The rational addition of a wetting and dispersing agent improves the dispersibility and solubility of the fertilizer; at the same time, it is more easily absorbed and utilized by plants, thereby helping plants to better absorb nutrients, greatly improving the crop's absorption rate of fertilizer, reducing fertilizer loss, and saving costs. DETAILED DESCRIPTION

[0028] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0029] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between any intermediate value within a stated value or stated range and any other stated value or intermediate value within the stated range is also encompassed by the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0030] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0031] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from the present invention. The present description and examples are intended to be illustrative only.

[0032] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0033] All “parts” described in the following examples are “parts by mass”.

[0034] The molecular weight of the carboxymethyl chitosan used in the following examples and comparative examples of the present invention is about 9,000.

[0035] Example 1

[0036] A preparation method of amino acid water-soluble fertilizer:

[0037] The amino acid water-soluble fertilizer is composed of the following raw materials in parts by mass: 12 parts of complex amino acids, 2 parts of ferrous sulfate, 3 parts of copper sulfate, 4 parts of zinc sulfate, 2 parts of manganese sulfate, 20 parts of carboxymethyl chitosan, 3 parts of potassium sulfate, 13 parts of potassium dihydrogen phosphate and 4 parts of a wetting and dispersing agent (sodium dodecylbenzene sulfonate).

[0038] The preparation of compound amino acids specifically includes:

[0039] A. Sun-dry pea straw to a moisture content of less than 10%, then grind it into a powder with a particle size of about 0.2 mm to obtain pea straw powder; take 10 kg of pea straw powder and add it to 50 kg of hydrochloric acid solution (mass concentration of 25%), then heat it to 80° C. After the pea straw powder is completely dissolved in the hydrochloric acid solution, cool it to obtain a hydrolyzate.

[0040] B. Add ammonium bicarbonate solution dropwise to the hydrolyzate to neutralize it to a pH of about 7 to obtain a composite amino acid aqueous solution.

[0041] C. Place the composite amino acid aqueous solution in a drying oven and dry it at low temperature (40° C.) to obtain the composite amino acid.

[0042] Preparation method:

[0043] (1) Weigh each raw material according to its mass fraction, mix and dissolve the composite amino acid and water in a mass ratio of 1:10 to obtain a composite amino acid solution.

[0044] (2) Carboxymethyl chitosan and water were mixed in a mass ratio of 4:1000, stirred to dissolve, and the pH value was adjusted to 3 with 0.1 mol / L hydrochloric acid. Then, the composite amino acid solution was added and stirred to disperse evenly. Then, a sodium polyphosphate solution with a concentration of 25 g / L (the mass ratio of sodium polyphosphate to carboxymethyl chitosan was 1:8) was added dropwise. The mixture was stirred for 3 h, centrifuged, and dried to obtain composite amino acid nanoparticles.

[0045] (3) The composite amino acid nanoparticles are dispersed in 1000 parts of water, and then a wetting dispersant is added, stirred and dispersed evenly, and finally ferrous sulfate, copper sulfate, zinc sulfate, manganese sulfate, potassium sulfate, and potassium dihydrogen phosphate are added and mixed and dissolved to obtain an amino acid water-soluble fertilizer.

[0046] Example 2

[0047] A preparation method of amino acid water-soluble fertilizer:

[0048] The amino acid water-soluble fertilizer is composed of the following raw materials in parts by mass: 10 parts of complex amino acids, 3 parts of ferrous sulfate, 2 parts of copper sulfate, 3 parts of zinc sulfate, 3 parts of manganese sulfate, 18 parts of carboxymethyl chitosan, 4 parts of potassium sulfate, 12 parts of potassium dihydrogen phosphate and 3 parts of wetting and dispersing agent (sodium dodecylbenzene sulfonate).

[0049] The preparation of compound amino acids specifically includes:

[0050] A. Sun-dry pea straw to a moisture content of less than 10%, then grind it into a powder with a particle size of about 0.1 mm to obtain pea straw powder: 10 kg of pea straw powder is added to 40 kg of hydrochloric acid solution (mass concentration is 23%), then heated to 85° C. After the pea straw powder is completely dissolved in the hydrochloric acid solution, cool it to obtain a hydrolyzate.

[0051] B. Add ammonium bicarbonate solution dropwise to the hydrolyzate to neutralize it to a pH of about 6 to obtain a composite amino acid aqueous solution.

[0052] C. Place the composite amino acid aqueous solution in a drying oven and dry it at low temperature (40° C.) to obtain the composite amino acid.

[0053] Preparation method:

[0054] (1) Weigh each raw material according to its mass fraction, mix and dissolve the composite amino acid and water in a mass ratio of 1:10 to obtain a composite amino acid solution.

[0055] (2) Carboxymethyl chitosan and water were mixed in a mass ratio of 4:1000, stirred to dissolve, and the pH value was adjusted to 4 with 0.1 mol / L hydrochloric acid. Then, the composite amino acid solution was added and stirred to disperse evenly. Then, a sodium polyphosphate solution with a concentration of 24 g / L (the mass ratio of sodium polyphosphate to carboxymethyl chitosan was 1:7) was added dropwise. The mixture was stirred for 2 h, centrifuged, and dried to obtain composite amino acid nanoparticles.

[0056] (3) The composite amino acid nanoparticles are dispersed in 1000 parts of water, and then a wetting dispersant is added, stirred and dispersed evenly, and finally ferrous sulfate, copper sulfate, zinc sulfate, manganese sulfate, potassium sulfate, and potassium dihydrogen phosphate are added and mixed and dissolved to obtain an amino acid water-soluble fertilizer.

[0057] Example 3

[0058] A preparation method of amino acid water-soluble fertilizer:

[0059] The amino acid water-soluble fertilizer is composed of the following raw materials in parts by mass: 13 parts of complex amino acids, 1 part of ferrous sulfate, 3 parts of copper sulfate, 5 parts of zinc sulfate, 2 parts of manganese sulfate, 19 parts of carboxymethyl chitosan, 4 parts of potassium sulfate, 15 parts of potassium dihydrogen phosphate and 4 parts of wetting and dispersing agent (potassium dodecylbenzenesulfonate).

[0060] The preparation of compound amino acids specifically includes:

[0061] A. Sun-dry pea straw to a moisture content of less than 10%, then grind it into a powder with a particle size of about 0.4 mm to obtain pea straw powder: 10 kg of pea straw powder is added to 60 kg of hydrochloric acid solution (mass concentration is 24%), then heated to 90° C. After the pea straw powder is completely dissolved in the hydrochloric acid solution, it is cooled to obtain a hydrolyzate.

[0062] B. Add ammonium bicarbonate solution dropwise to the hydrolyzate to neutralize it to a pH of about 8 to obtain a composite amino acid aqueous solution.

[0063] C. Place the composite amino acid aqueous solution in a drying oven and dry it at low temperature (40° C.) to obtain the composite amino acid.

[0064] Preparation method:

[0065] (1) Weigh each raw material according to its mass fraction, mix and dissolve the composite amino acid and water in a mass ratio of 1:10 to obtain a composite amino acid solution.

[0066] (2) Carboxymethyl chitosan and water were mixed in a mass ratio of 4:1000, stirred to dissolve, and the pH value was adjusted to 3 with 0.1 mol / L hydrochloric acid. Then, the composite amino acid solution was added and stirred to disperse evenly. Then, a sodium polyphosphate solution with a concentration of 30 g / L (the mass ratio of sodium polyphosphate to carboxymethyl chitosan was 1:8) was added dropwise. The mixture was stirred for 3 h, centrifuged, and dried to obtain composite amino acid nanoparticles.

[0067] (3) The composite amino acid nanoparticles are dispersed in 1000 parts of water, and then a wetting dispersant is added, stirred and dispersed evenly, and finally ferrous sulfate, copper sulfate, zinc sulfate, manganese sulfate, potassium sulfate, and potassium dihydrogen phosphate are added and mixed and dissolved to obtain an amino acid water-soluble fertilizer.

[0068] Example 4

[0069] A preparation method of amino acid water-soluble fertilizer:

[0070] The amino acid water-soluble fertilizer is composed of the following raw materials in parts by mass: 15 parts of complex amino acids, 2 parts of ferrous sulfate, 4 parts of copper sulfate, 3 parts of zinc sulfate, 3 parts of manganese sulfate, 18 parts of carboxymethyl chitosan, 3 parts of potassium sulfate, 10 parts of potassium dihydrogen phosphate and 3 parts of wetting and dispersing agent (potassium dodecylbenzenesulfonate).

[0071] The preparation of compound amino acids specifically includes:

[0072] A. Sun-dry pea straw to a moisture content of less than 10%, then grind it into a powder with a particle size of about 0.5 mm to obtain pea straw powder: 10 kg of pea straw powder is added to 70 kg of hydrochloric acid solution (mass concentration is 25%), then heated to 90° C. After the pea straw powder is completely dissolved in the hydrochloric acid solution, cool it to obtain a hydrolyzate.

[0073] B. Add ammonium bicarbonate solution dropwise to the hydrolyzate to neutralize it to a pH of about 7 to obtain a composite amino acid aqueous solution.

[0074] C. Place the composite amino acid aqueous solution in a drying oven and dry it at low temperature (40° C.) to obtain the composite amino acid.

[0075] Preparation method:

[0076] (1) Weigh each raw material according to its mass fraction, mix and dissolve the composite amino acid and water in a mass ratio of 1:10 to obtain a composite amino acid solution.

[0077] (2) Carboxymethyl chitosan and water were mixed in a mass ratio of 4:1000, stirred to dissolve, and the pH value was adjusted to 4 with 0.1 mol / L hydrochloric acid. Then, the composite amino acid solution was added and stirred to disperse evenly. Then, a sodium polyphosphate solution with a concentration of 29 g / L (the mass ratio of sodium polyphosphate to carboxymethyl chitosan was 1:7) was added dropwise. The mixture was stirred for 2 h, centrifuged, and dried to obtain composite amino acid nanoparticles.

[0078] (3) The composite amino acid nanoparticles are dispersed in 1000 parts of water, and then a wetting dispersant is added, stirred and dispersed evenly, and finally ferrous sulfate, copper sulfate, zinc sulfate, manganese sulfate, potassium sulfate, and potassium dihydrogen phosphate are added and mixed and dissolved to obtain an amino acid water-soluble fertilizer.

[0079] Comparative Example 1

[0080] The same as Example 1, except that the mass ratio of sodium polyphosphate to carboxymethyl chitosan in step (2) is 1:12.

[0081] In this comparative example, composite amino acid nanoparticles could not be formed due to the small amount of sodium polyphosphate used.

[0082] Comparative Example 2

[0083] The same as Example 1, except that the mass ratio of sodium polyphosphate to carboxymethyl chitosan in step (2) is 1:5.

[0084] In this comparative example, due to the large amount of sodium polyphosphate used, the composite amino acid nanoparticles agglomerated.

[0085] Comparative Example 3

[0086] Same as Example 1, except that the pH value in step (2) is 2.

[0087] In this example, due to the low pH value, the solution remained clear and composite amino acid nanoparticles could not be prepared.

[0088] Comparative Example 4

[0089] Same as Example 1, except that the pH value in step (2) is 6.

[0090] The carboxymethyl chitosan solution in this example precipitated, and the composite amino acid nanoparticles could not be prepared.

[0091] Comparative Example 5

[0092] Same as Example 1, except that sodium dodecylbenzenesulfonate is replaced with an equal mass of Tween 20.

[0093] Comparative Example 6

[0094] The same as Example 1, except that in step (2), the carboxymethyl chitosan is replaced by chitosan of equal mass (molecular weight of 20,000).

[0095] Effect Example 1

[0096] Slow-release experiment of fertilizer: Determined by water dissolution rate method according to the national standard for slow-release fertilizer (GB / T23348-2009).

[0097] 20 mL of the water-soluble fertilizer prepared in Examples 1 to 4 and Comparative Example 6 (prepared on the same day) was measured and placed in a 250 mL glass bottle. 100 mL of water was added, the bottle was sealed with a lid, and the bottle was placed in a 25 ° C biochemical constant temperature incubator. Samples were taken at 1, 10, 20, 40, and 60 d, respectively. The nitrogen release amount was tested using an automatic analyzer, and the cumulative nitrogen release rate was calculated. The calculation formula is as follows: v = Wn / W, where Wn is the mass fraction of the nitrogen release amount measured on the nth day, and W is the mass fraction of the total nitrogen. The results are shown in Table 1.

[0098] Table 1 Cumulative nitrogen release rate

[0099]

[0100] As can be seen from Table 1, the water-soluble fertilizer prepared by the present invention can continuously and stably release amino acids to provide nutrients for plants, which can not only meet the long-term nutrient supply of plants, but also avoid the phenomenon of excessive accumulation of nutrients in the plant body, and achieve a balanced state of various nutrients.

[0101] Effect Example 2

[0102] In a certain tangerine orchard (with a planting density of approximately 60 trees per mu), seven plots of 0.5 mu each were selected as experimental plots. During the new shoot and fruiting stages of the tangerine trees, amino acid water-soluble fertilizers prepared in Examples 1 to 4 of the present invention and Comparative Examples 5 to 6 were sprayed (sprayed after dilution 50 times, with 50 L sprayed per mu each time). A control group was sprayed with a conventional amino acid water-soluble fertilizer containing the following ingredients: 12 parts of a composite amino acid, 2 parts of ferrous sulfate, 3 parts of copper sulfate, 4 parts of zinc sulfate, 2 parts of manganese sulfate, 3 parts of potassium sulfate, 13 parts of potassium dihydrogen phosphate, 4 parts of a wetting and dispersing agent (sodium dodecylbenzene sulfonate), and 1000 parts of water. The amino acid water-soluble fertilizer in the control group was also diluted 50 times and sprayed. After the tangerines matured, the yield of the tangerines was counted, as shown in Table 2.

[0103] Table 2 Output of Sugar Orange

[0104] Grouping Yield of sugar oranges (kg / mu) Example 1 8754 Example 2 8684 Example 3 8721 Example 4 8699 Comparative Example 5 8427 Comparative Example 6 8013 control group 7541

[0105] As can be seen from Table 2, the application of the amino acid water-soluble fertilizer prepared by the present invention can significantly increase the yield of sugar oranges.

[0106] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. An amino acid water-soluble fertilizer, characterized in that: The invention comprises the following raw materials in parts by weight: 10-15 parts of composite amino acid, 1-3 parts of ferrous sulfate, 2-4 parts of copper sulfate, 3-5 parts of zinc sulfate, 2-3 parts of manganese sulfate, 18-20 parts of carboxymethyl chitosan, 3-4 parts of potassium sulfate, 10-15 parts of potassium dihydrogen phosphate and 3-4 parts of wetting and dispersing agent; The wetting and dispersing agent is sodium dodecylbenzene sulfonate; the molecular weight of the carboxymethyl chitosan is 8500-9500; The method for preparing the amino acid water-soluble fertilizer is characterized in that it comprises the following steps: (1) weighing each raw material according to the mass fraction, dissolving the composite amino acid in water to obtain a composite amino acid solution; (2) dissolving carboxymethyl chitosan in water, adjusting the pH value to acidic, then adding the composite amino acid solution, stirring and dispersing evenly, dropping a polyphosphate solution, stirring and reacting, centrifuging, and drying to obtain composite amino acid nanoparticles; (3) dispersing the composite amino acid nanoparticles in water, then adding a wetting dispersant, stirring and dispersing them evenly, and finally adding ferrous sulfate, copper sulfate, zinc sulfate, manganese sulfate, potassium sulfate, and potassium dihydrogen phosphate, mixing and dissolving them to obtain the amino acid water-soluble fertilizer; In step (2), the pH value is 3 to 4; In step (2), the concentration of the polyphosphate solution is 24-30 g / L; In step (2), the mass ratio of polyphosphate to carboxymethyl chitosan in the polyphosphate solution is 1:(7-8); the polyphosphate is sodium polyphosphate; In step (2), the stirring reaction time is 2 to 3 hours; The preparation of the composite amino acid specifically comprises: A. Crush the crop straw and add it to a hydrochloric acid solution, heat it, then drop an ammonium bicarbonate solution and neutralize it to a pH value of 6 to 8 to obtain a composite amino acid aqueous solution; B. placing the composite amino acid aqueous solution in a drying oven for low-temperature drying to obtain the composite amino acid.

2. The amino acid water-soluble fertilizer according to claim 1, characterized in that In step A, the mass concentration of the hydrochloric acid solution is 23-25%; the temperature of the heating treatment is 80-90°C.

3. The amino acid water-soluble fertilizer according to claim 1, characterized in that In step A, the powder is crushed to a particle size of 0.1 to 0.5 mm.

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