Special slow / controlled-release fertilizer composition for winter wheat and preparation method of special slow / controlled-release fertilizer composition

Abstract

The invention relates to the technical field of fertilizers, in particular to a special slow / controlled-release fertilizer composition for winter wheat and a preparation method thereof, and the special slow / controlled-release fertilizer composition comprises a seaweed-derived microbial fertilizer, a sulfur-doped fertilizer and castor oil-based coated urea, wherein the mass ratio of the seaweed source microbial fertilizer to the sulfur blended fertilizer to the castor oil based coated urea is (1-1.5): (5-6): (3-4). The seaweed-derived microbial fertilizer, the sulfur-blended fertilizer and the castor oil-based coated urea are combined for use, so that the use amount of the fertilizer is reduced while balanced controlled release of sulfur, nitrogen, phosphorus and potassium is realized.

Description

Technical Field

[0001] The invention relates to the technical field of fertilizers, and in particular to a slow-release fertilizer composition special for winter wheat and a preparation method thereof. Background Art

[0002] Wheat grains are rich in carbohydrates, proteins, fats, vitamins and a variety of mineral elements that are beneficial to the human body. They are easy to process and durable in storage and transportation. They are not only the raw materials for processing various staple foods and non-staple foods in most countries in the world, but also the main reserve food of various countries and the main food variety in the world's food trade. Wheat can be divided into spring wheat and winter wheat according to the planting time. Winter wheat has a long growth cycle and more sufficient nutrient accumulation. Its yield and quality are better than spring wheat. However, since winter wheat is sown in autumn, it has a long growth period during the wintering stage. It requires a lot of nutrients during the leafing stage and the greening to flowering stage. It is usually necessary to apply at least two topdressings before wintering (or during the greening period) and during the jointing stage to supplement nutrients for winter wheat. The topdressing methods of winter wheat mainly include hole application, broadcast application, topdressing with a horn plow and topdressing with a seeder. Hole application, broadcast application and topdressing with a horn plow are time-consuming and labor-intensive, while topdressing with a seeder can easily break the root stems of wheat during the fertilization process.

[0003] The invention patent with publication number CN117263751A discloses a controlled-release compound fertilizer, including polyurethane-coated controlled-release nitrogen fertilizer, potash fertilizer, and phosphate fertilizer. The patent uses polyurethane-coated nitrogen fertilizer to achieve controlled release of nitrogen fertilizer, improves the utilization rate of nitrogen fertilizer, and reduces the topdressing operation during the greening period to a certain extent. However, since the controlled-release compound fertilizer disclosed in the patent only includes nitrogen fertilizer, potash fertilizer, and phosphate fertilizer, and only the nitrogen fertilizer is coated with polyurethane, it is not only impossible to achieve balanced controlled release of multiple nutrient elements, but also unable to reduce the use of chemical fertilizers. Summary of the invention

[0004] In view of the technical problems that existing controlled-release compound fertilizers cannot achieve balanced controlled release of multiple nutrient elements and cannot reduce the use of chemical fertilizers, the present invention provides a slow-release fertilizer composition special for winter wheat and a preparation method thereof, which combines seaweed-derived microbial fertilizers, sulfur-blended fertilizers and castor oil-based coated urea to achieve balanced controlled release of sulfur, nitrogen, phosphorus and potassium while reducing the use of chemical fertilizers.

[0005] In a first aspect, the present invention provides a slow-release fertilizer composition for winter wheat, comprising seaweed-derived microbial fertilizer, sulfur-blended fertilizer, and castor oil-based coated urea; Wherein, the mass ratio of seaweed-derived microbial fertilizer, sulfur-blended fertilizer and castor oil-based coated urea is 1-1.5:5-6:3-4, preferably 1:5:4; The seaweed-derived microbial fertilizer contains zinc sulfate heptahydrate, ferrous sulfate heptahydrate, borax decahydrate, seaweed-derived microbial agent and nutrient accumulator; in the seaweed-derived microbial fertilizer, the weight ratio of zinc sulfate heptahydrate, ferrous sulfate heptahydrate, borax decahydrate, seaweed-derived microbial agent and nutrient accumulator is 5-7:2-4:1-3:25-45:0.5-0.8; The sulfur-blended fertilizer contains 16-22 parts by weight of urea, 10-15 parts by weight of monoammonium phosphate, 5-8 parts by weight of potassium chloride and 6-9 parts by weight of sulfur; The coating material of castor oil-based coated urea is castor oil-based polymer material, and the mass percentage of castor oil-based polymer material in castor oil-based coated urea is 2%-3%.

[0006] Furthermore, the seaweed-derived microbial agent is seaweed powder adsorbed with microbial fermentation liquid, the mass ratio of seaweed powder to microbial fermentation liquid is 1.5-3:1, and the number of viable bacteria of the seaweed-derived microbial agent is 6×10 7 CFU / g.

[0007] Furthermore, the microbial fermentation broth is a fermentation broth of nitrogen-fixing bacteria and / or a fermentation broth of Bacillus subtilis.

[0008] Furthermore, the seaweed is at least one of kelp, brown algae, and Sargassum.

[0009] Furthermore, the nutrient retainer is at least one of montmorillonite, medical stone, and activated carbon.

[0010] Furthermore, the preparation method of the sulfur-blended fertilizer comprises the following steps: Step 1: crushing urea, monoammonium phosphate and potassium chloride respectively; Step 2: Evenly mix the crushed urea, monoammonium phosphate and potassium chloride to obtain a blended fertilizer; Step 3: Heat and melt the sulfur, add it into the blended fertilizer, mix evenly, and then granulate it.

[0011] Furthermore, the castor oil-based polymer material is castor oil-based polyurethane or castor oil-based polyurethane acrylate, and in the castor oil-based polymer material, the mass percentage of castor oil monomer units is 10%-30%.

[0012] Furthermore, the inner core particles of the castor oil-based coated urea are urea particles with a polished surface and a round shape, and the particle size of the urea particles is 4-7 mm.

[0013] In a second aspect, the present invention also provides a method for preparing the above-mentioned slow-release fertilizer composition for winter wheat, wherein the slow-release fertilizer composition for winter wheat is prepared by uniformly mixing seaweed-derived microbial fertilizer, sulfur-blended fertilizer and castor oil-based coated urea.

[0014] The beneficial effects of the present invention are: The invention provides a special slow-release fertilizer composition for winter wheat and a preparation method thereof, wherein seaweed-derived microbial fertilizer, sulfur-blended fertilizer and castor oil-based coated urea are compounded in proportion, and the seaweed-derived microbial fertilizer is used to adjust the physical and chemical properties of the soil, thereby improving the nitrogen fixation, phosphorus fixation, water retention and disease resistance of the soil; the sulfur-blended fertilizer is used to supplement the sulfur element in the soil while realizing the slow release of phosphorus, nitrogen, potassium and sulfur; and the castor oil-based coated urea is used to realize the slow release of urea over a long period of time. The present application uses nutrient storage agents, sulfur and castor oil-based polymer materials to control the release of different nutrient elements to different degrees, fully meeting the growth needs of winter wheat at different stages, improving the utilization rate of multiple elements such as sulfur, zinc, iron, boron, nitrogen and phosphorus, and reducing the use of chemical fertilizers. DETAILED DESCRIPTION

[0015] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0016] Example 1 A slow-release fertilizer composition specially used for winter wheat is prepared by uniformly mixing seaweed-derived microbial fertilizer, sulfur-blended fertilizer and castor oil-based coated urea in a mass ratio of 1:5:4.

[0017] 1. Preparation of seaweed-derived microbial fertilizer 1-1-1 Preparation of seaweed-derived microbial agent: (1) Grind dried kelp into 60-80 mesh to obtain kelp powder; (2) Evenly mix the kelp powder and the fermentation liquid of nitrogen-fixing bacteria at a mass ratio of 1.5:1, so that the kelp powder can fully absorb the fermentation liquid of nitrogen-fixing bacteria and obtain a viable bacterial count of 6×10 7 CFU / g of seaweed-derived microbial agent.

[0018] 1-1-2 Preparation of seaweed-derived microbial fertilizer: Evenly mix 5 parts by weight of zinc sulfate heptahydrate, 4 parts by weight of ferrous sulfate heptahydrate, 3 parts by weight of borax decahydrate, 25 parts by weight of seaweed-derived microbial agent and 0.5 parts by weight of montmorillonite to obtain seaweed-derived microbial fertilizer.

[0019] (II) Preparation of sulfur-blended fertilizers Step 1-2-1: Weigh 16 parts by weight of urea, 12 parts by weight of monoammonium phosphate and 7 parts by weight of potassium chloride and crush them separately.

[0020] Step 1-2-2: Evenly mix the crushed urea, monoammonium phosphate and potassium chloride to obtain a blended fertilizer.

[0021] Step 1-2-3: Heat and melt 6 parts by weight of sulfur, add it to the blended fertilizer, mix evenly, and then granulate to obtain a sulfur blended fertilizer.

[0022] (III) Preparation of castor oil-based coated urea 1-3-1 Preparation of core particles The surfaces of the urea particles are polished to obtain round urea particles, thereby obtaining inner core particles with a particle size of 4-7 mm.

[0023] 1-3-2 Preparation of castor oil-based polyurethane coated urea S1: Synthesizing castor oil-based polyurethane prepolymer using castor oil and isophorone diisocyanate as raw materials; S2: Add the inner core particles to the castor oil-based polyurethane prepolymer and mix them evenly, then add 1,4-butanediol to extend the chain, and dry after the reaction to obtain castor oil-based polyurethane coated urea. The mass percentage of castor oil-based polyurethane in castor oil-based polyurethane coated urea is 2.2%. In the castor oil-based polyurethane, the mass percentage of castor oil monomer unit is 10%.

[0024] Example 2 A slow-release controlled-release fertilizer composition specially used for winter wheat is prepared by uniformly mixing seaweed-derived microbial fertilizer, sulfur-blended fertilizer and castor oil-based coated urea in a mass ratio of 1:6:3.

[0025] 1. Preparation of seaweed-derived microbial fertilizer 2-1-1 Preparation of seaweed-derived microbial inoculant: (1) Crush the dried brown algae to 60-80 mesh to obtain brown algae powder; (2) Evenly mix the brown algae powder and the fermentation liquid of Bacillus subtilis at a mass ratio of 2:1, so that the brown algae powder can fully absorb the fermentation liquid of Bacillus subtilis, and obtain a viable bacterial count of 6×10 7 CFU / g of seaweed-derived microbial agent.

[0026] 2-1-2 Preparation of seaweed-derived microbial fertilizer: Evenly mix 7 parts by weight of zinc sulfate heptahydrate, 3 parts by weight of ferrous sulfate heptahydrate, 2 parts by weight of borax decahydrate, 30 parts by weight of seaweed-derived microbial agent and 0.8 parts by weight of activated carbon to obtain seaweed-derived microbial fertilizer.

[0027] (II) Preparation of sulfur-blended fertilizers Step 2-2-1: Weigh 22 parts by weight of urea, 15 parts by weight of monoammonium phosphate and 5 parts by weight of potassium chloride and crush them separately.

[0028] Step 2-2-2: Evenly mix the crushed urea, monoammonium phosphate and potassium chloride to obtain a blended fertilizer.

[0029] Step 2-2-3: Heat and melt 8 parts by weight of sulfur, add it to the blended fertilizer, mix evenly, and then granulate to obtain a sulfur blended fertilizer.

[0030] (III) Preparation of castor oil-based coated urea 2-3-1 Preparation of core particles The surfaces of the urea particles are polished to obtain round urea particles, thereby obtaining inner core particles with a particle size of 4-7 mm.

[0031] 2-3-2 Preparation of castor oil-based polyurethane coated urea S1: Synthesizing castor oil-based polyurethane prepolymer using castor oil and toluene diisocyanate as raw materials; S2: Add the inner core particles to the castor oil-based polyurethane prepolymer and mix them evenly, then add 1,4-butanediol to extend the chain, and dry after the reaction to obtain castor oil-based polyurethane coated urea. The mass percentage of castor oil-based polyurethane in castor oil-based polyurethane coated urea is 3%. The mass percentage of castor oil monomer units in castor oil-based polyurethane is 20%.

[0032] Example 3 A slow-release fertilizer composition specially used for winter wheat is prepared by uniformly mixing seaweed-derived microbial fertilizer, sulfur-blended fertilizer and castor oil-based coated urea in a mass ratio of 1:5:4.

[0033] 1. Preparation of seaweed-derived microbial fertilizer 1-1-1 Preparation of seaweed-derived microbial agent: (1) Crush dried Sargassum to 60-80 mesh to obtain Sargassum powder; (2) Evenly mix the Sargassum powder, the fermentation liquid of nitrogen-fixing bacteria and the fermentation liquid of Bacillus subtilis at a mass ratio of 3:1, so that the Sargassum powder can fully absorb the fermentation liquid of nitrogen-fixing bacteria and the fermentation liquid of Bacillus subtilis, and obtain a viable bacterial count of 6×10 7 CFU / g of seaweed-derived microbial agent.

[0034] 1-1-2 Preparation of seaweed-derived microbial fertilizer: Evenly mix 6 parts by weight of zinc sulfate heptahydrate, 2 parts by weight of ferrous sulfate heptahydrate, 3 parts by weight of borax decahydrate, 45 parts by weight of seaweed-derived microbial agent and 0.7 parts by weight of medical stone powder to obtain seaweed-derived microbial fertilizer.

[0035] (II) Preparation of sulfur-blended fertilizers Step 1-2-1: Weigh 21 parts by weight of urea, 14 parts by weight of monoammonium phosphate and 8 parts by weight of potassium chloride and crush them separately.

[0036] Step 1-2-2: Evenly mix the crushed urea, monoammonium phosphate and potassium chloride to obtain a blended fertilizer.

[0037] Step 1-2-3: Heat and melt 9 parts by weight of sulfur, add it to the blended fertilizer, mix evenly, and then granulate to obtain a sulfur blended fertilizer.

[0038] (III) Preparation of castor oil-based coated urea 1-3-1 Preparation of core particles The surfaces of the urea particles are polished to obtain round urea particles, thereby obtaining inner core particles with a particle size of 4-7 mm.

[0039] 1-3-2 Preparation of castor oil-based polyurethane coated urea S1: Synthesizing castor oil-based polyurethane prepolymer using castor oil and isophorone diisocyanate as raw materials; S2: Add 1,4-butanediol to the castor oil-based polyurethane prepolymer for chain extension, then add the inner core particles, dry after the reaction is completed, and obtain castor oil-based polyurethane coated urea. The mass percentage of castor oil-based polyurethane in castor oil-based polyurethane coated urea is 2.6%. In the castor oil-based polyurethane, the mass percentage of castor oil monomer unit is 30%.

[0040] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is only the preparation of the sulfur-blended fertilizer. The preparation method of the sulfur-blended fertilizer is as follows: 22 parts by weight of urea, 15 parts by weight of monoammonium phosphate, 5 parts by weight of potassium chloride and 8 parts by weight of sulfur are weighed and crushed respectively, and the crushed urea, monoammonium phosphate, potassium chloride and sulfur are evenly mixed and granulated.

[0041] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the castor oil-based polyurethane coating is not used to polish the round urea particles.

[0042] Application Example 1 The compositions prepared in Examples 1-3 and Comparative Examples 1-2 were tested for relevant properties according to the national standard "Slow-release Fertilizer" (GB / T 23348-2009). The slow-release fertilizer should be immersed in 25°C still water for 24 hours with an initial nitrogen release rate of less than 15% and a 28-day cumulative nitrogen release rate of less than 80%. The experimental results are shown in Table 1.

[0043] Table 1 Nitrogen release rates of the compositions prepared in Examples 1-3 and Comparative Examples 1-2

[0044] Application Example 2 Field application: Before sowing, the compositions prepared in Examples 1-3 and Comparative Examples 1-2 were evenly spread in different areas of the same field, each area of ​​8 mu, and then plowed and planted. No topdressing was applied during the growth period of winter wheat. During the harvest period, 120 winter wheat plants were randomly selected from each area, and the average values ​​of plant height, ear length, number of grains per ear, thousand-grain weight and yield were calculated. The statistical results are shown in Table 2.

[0045] Table 2 Statistical data of the compositions prepared in Examples 1-3 and Comparative Examples 1-2 in field applications

[0046] Although the present invention has been described in detail by combining the preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person skilled in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions shall be within the scope of the present invention. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, and these shall be within the scope of protection of the present invention.

Claims

1. A slow-release fertilizer composition for winter wheat, characterized in that: These include seaweed-derived microbial fertilizers, sulfur-blended fertilizers, and castor oil-based coated urea; The mass ratio of the seaweed-derived microbial fertilizer, the sulfur-blended fertilizer and the castor oil-based coated urea is 1-1.5:5-6:3-4; The seaweed-derived microbial fertilizer contains zinc sulfate heptahydrate, ferrous sulfate heptahydrate, borax decahydrate, seaweed-derived microbial agent and nutrient accumulator; in the seaweed-derived microbial fertilizer, the weight ratio of zinc sulfate heptahydrate, ferrous sulfate heptahydrate, borax decahydrate, seaweed-derived microbial agent and nutrient accumulator is 5-7:2-4:1-3:25-45:0.5-0.8; The sulfur-blended fertilizer contains 16-22 parts by weight of urea, 10-15 parts by weight of monoammonium phosphate, 5-8 parts by weight of potassium chloride and 6-9 parts by weight of sulfur; The coating material of castor oil-based coated urea is castor oil-based polymer material, and the mass percentage of castor oil-based polymer material in castor oil-based coated urea is 2%-3%.

2. A slow-release fertilizer composition for winter wheat as claimed in claim 1, characterized in that: The seaweed-derived microbial agent is seaweed powder adsorbed with microbial fermentation liquid. The mass ratio of seaweed powder to microbial fermentation liquid is 1.5-3:

1. The number of viable bacteria of the seaweed-derived microbial agent is 6×10 7 CFU / g.

3. A slow-release fertilizer composition for winter wheat as claimed in claim 2, characterized in that: The microbial fermentation broth is a fermentation broth of nitrogen-fixing bacteria and / or a fermentation broth of Bacillus subtilis.

4. A slow-release fertilizer composition for winter wheat as claimed in claim 2, characterized in that: The seaweed is at least one of kelp, brown algae, and sargassum.

5. A slow-release fertilizer composition for winter wheat as claimed in claim 1, characterized in that: The nutrient retainer is at least one of montmorillonite, medical stone and activated carbon.

6. A slow-release fertilizer composition for winter wheat as claimed in claim 1, characterized in that: The method for preparing the sulfur-blended fertilizer comprises the following steps: Step 1: crushing urea, monoammonium phosphate and potassium chloride respectively; Step 2: Evenly mix the crushed urea, monoammonium phosphate and potassium chloride to obtain a blended fertilizer; Step 3: Heat and melt the sulfur, add it into the blended fertilizer, mix evenly, and then granulate it.

7. A slow-release fertilizer composition for winter wheat as claimed in claim 1, characterized in that: The castor oil-based polymer material is castor oil-based polyurethane or castor oil-based polyurethane acrylate. In the castor oil-based polymer material, the mass percentage of castor oil monomer units is 10%-30%.

8. The slow-release fertilizer composition for winter wheat according to claim 1, characterized in that: The inner core particles of castor oil-based coated urea are urea particles with a polished surface and a full circle.

9. A method for preparing the slow-release and controlled-release fertilizer composition for winter wheat according to any one of claims 1 to 8, characterized in that: The slow-release fertilizer composition specially used for winter wheat is prepared by uniformly mixing seaweed-derived microbial fertilizer, sulfur-blended fertilizer and castor oil-based coated urea.

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