CN112592233A - Soil testing formula fertilizer and preparation method thereof - Google Patents
Soil testing formula fertilizer and preparation method thereof Download PDFInfo
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- CN112592233A CN112592233A CN202011603619.3A CN202011603619A CN112592233A CN 112592233 A CN112592233 A CN 112592233A CN 202011603619 A CN202011603619 A CN 202011603619A CN 112592233 A CN112592233 A CN 112592233A
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- fertilizer
- pha
- coating layer
- fertilizer core
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05B—PHOSPHATIC FERTILISERS
- C05B1/00—Superphosphates, i.e. fertilisers produced by reacting rock or bone phosphates with sulfuric or phosphoric acid in such amounts and concentrations as to yield solid products directly
- C05B1/02—Superphosphates
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05B—PHOSPHATIC FERTILISERS
- C05B13/00—Fertilisers produced by pyrogenic processes from phosphatic materials
- C05B13/02—Fertilisers produced by pyrogenic processes from phosphatic materials from rock phosphates
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
- C05G3/40—Mixtures of one or more fertilisers with additives not having a specially fertilising activity for affecting fertiliser dosage or release rate; for affecting solubility
-
- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G3/00—Mixtures of one or more fertilisers with additives not having a specially fertilising activity
- C05G3/80—Soil conditioners
-
- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G5/00—Fertilisers characterised by their form
- C05G5/10—Solid or semi-solid fertilisers, e.g. powders
- C05G5/12—Granules or flakes
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- C—CHEMISTRY; METALLURGY
- C05—FERTILISERS; MANUFACTURE THEREOF
- C05G—MIXTURES OF FERTILISERS COVERED INDIVIDUALLY BY DIFFERENT SUBCLASSES OF CLASS C05; MIXTURES OF ONE OR MORE FERTILISERS WITH MATERIALS NOT HAVING A SPECIFIC FERTILISING ACTIVITY, e.g. PESTICIDES, SOIL-CONDITIONERS, WETTING AGENTS; FERTILISERS CHARACTERISED BY THEIR FORM
- C05G5/00—Fertilisers characterised by their form
- C05G5/30—Layered or coated, e.g. dust-preventing coatings
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Pest Control & Pesticides (AREA)
- Soil Sciences (AREA)
- Fertilizers (AREA)
Abstract
The invention discloses a soil testing formula fertilizer, which comprises a fertilizer core and a coating layer coated on the surface of the fertilizer core, wherein the fertilizer core is in a spherical shape with the diameter of 2-3mm, the thickness of the coating layer is not more than 0.5mm, the raw material of the fertilizer core comprises clay accounting for 8-10% of the total mass of the fertilizer core, the coating layer is made of PHA and PVA, and the preparation method of the coating layer comprises the following steps: dissolving PHA in heated chloroform to form PHA solution, dispersing PVA grains in PHA solution, spraying the obtained mixed system on the surface of fertilizer core, and forming a coating layer on the surface of fertilizer core after the chloroform is volatilized. The soil testing formula fertilizer can keep the fertilizer efficiency for a long time, can release the fertility continuously even under the scouring of irrigation water and rainwater, does not need to be applied again in a short time, and improves the utilization rate of the fertilizer due to less fertilizer loss.
Description
Technical Field
The invention belongs to the field of fertilizers, and particularly relates to a soil testing formula fertilizer and a preparation method thereof.
Background
The soil testing formula fertilizer is mostly applied to balanced fertilization of field grain crops and generally comprises three processes, namely soil testing and soil sampling to determine the content of soil nutrients; secondly, formulation, namely, developing a prescription and dispensing according to the prescription according to nutrition required by crops after nutrient diagnosis of soil; thirdly, reasonable fertilization, namely scientific application of the formulated fertilizer under the guidance of agricultural science and technology personnel.
In the process of formulation, the fertilizers are often simply mixed together to form a compound fertilizer, and the fertilizer which is simply mixed together is applied, particularly when the fertilizers are water-soluble fertilizers, the fertilizer effect time is not long, most of the fertilizers are lost along with the washing of rainwater and irrigation water, so that the repeated application is needed in a short time, on one hand, waste is caused, and meanwhile, the lost fertilizers can cause environmental pollution.
Disclosure of Invention
In order to solve the problems, the invention provides a soil testing formula fertilizer and a preparation method thereof.
In order to achieve the purpose, the invention adopts the following technical scheme:
the soil testing formula fertilizer comprises a fertilizer core and a coating layer coated on the surface of the fertilizer core, wherein the fertilizer core is in a spherical shape with the diameter of 2-3mm, the thickness of the coating layer is not more than 0.5mm, the raw material of the fertilizer core comprises clay accounting for 8-10% of the total mass of the fertilizer core, the coating layer is made of PHA and PVA, and the preparation method of the coating layer comprises the following steps: dissolving PHA in heated chloroform to form PHA solution, dispersing PVA grains in PHA solution, spraying the obtained mixed system on the surface of fertilizer core, and forming a coating layer on the surface of fertilizer core after the chloroform is volatilized.
A preparation method of a soil testing formula fertilizer comprises the following steps:
(1) preparing a fertilizer core: preparing a fertilizer core raw material as required, wherein the mass of clay accounts for 8-10% of the total mass of the fertilizer core, and other common fertilizers are prepared according to the soil requirement; spraying water mist on the prepared raw materials under the stirring condition, uniformly mixing, forming and drying to obtain spherical fertilizer cores with the diameter of 2-3 mm;
(2) preparing a coating layer solution: dissolving PHA in heated chloroform to obtain PHA solution, and dispersing PVA grains into the PHA solution to obtain a mixed system containing PHA and PVA;
(3) preparing a soil testing formula fertilizer: and (3) spraying the mixed system obtained in the step (2) on the surface of the spherical fertilizer core obtained in the step (1), and drying to evaporate the solvent.
Further, the particle size of the PVA particles is 200-500 μm.
Furthermore, the concentration of PHA in the PHA solution is 8-10 g/L.
Further, the mass ratio of the PHA to the PVA is 6: 4.
Further, the temperature of chloroform was 90 ℃.
Compared with the prior art, the invention has the beneficial effects that:
the soil testing formula fertilizer can keep the fertilizer efficiency for a long time, can release the fertility continuously even under the scouring of irrigation water and rainwater, does not need to be applied again in a short time, and improves the utilization rate of the fertilizer due to less fertilizer loss.
Drawings
FIG. 1 is a schematic structural diagram of a soil testing formula fertilizer of the invention;
in the figure: 1-fertilizer core and 2-coating layer.
Detailed Description
The present invention will be further described with reference to the following examples, which are intended to illustrate only some, but not all, of the embodiments of the present invention. All other embodiments that can be obtained by a person skilled in the art based on the embodiments of the present invention without any creative effort belong to the protection scope of the present invention.
The soil testing formula fertilizer comprises a fertilizer core and a coating layer coated on the surface of the fertilizer core, wherein the fertilizer core is in a spherical shape with the diameter of 2-3mm, the thickness of the coating layer is not more than 0.5mm, the raw material of the fertilizer core comprises clay accounting for 8-10% of the total mass of the fertilizer core, the coating layer is made of PHA (polyhydroxyalkanoate) and PVA (polyvinyl alcohol), and the preparation method of the coating layer comprises the following steps: dissolving PHA in heated chloroform to form PHA solution, dispersing PVA grains in PHA solution, spraying the obtained mixed system on the surface of fertilizer core, and forming a coating layer on the surface of fertilizer core after the chloroform is volatilized.
In the scheme, the soil testing formula fertilizer consists of a fertilizer core and a coating layer coated on the surface of the fertilizer core, wherein the coating layer is made of PHA and PVA, the PHA plays a role in forming a film to form a main structure of the coating layer, the PVA is embedded in the PHA film in a particle form, when irrigation water or rainwater acts on the soil testing formula fertilizer, PVA particles in the coating layer are dissolved in water, the coating layer forms a film with a plurality of holes, the fertilizer core is exposed at the moment, the fertilizer core in the coating layer is slowly and continuously dissolved out, the fertilizer efficiency is prolonged, and the PHA is degradable plastic and can not pollute the environment; the fertilizer core comprises clay and other common fertilizers, the other common fertilizers can be compounded according to the actual condition of soil, the clay accounts for 8-10% of the total mass, the clay mainly plays three roles, firstly, the clay is used as an adhesive, all the components are bonded together in the process of mixing all the raw materials of the fertilizer core, the formed spherical fertilizer core is not easy to break in the process of transferring, secondly, the clay is used as a mineral raw material and provides elements such as magnesium, iron, calcium and the like, thirdly, after the fertilizer is applied by a soil testing formula fertilizer, the clay can be used as a slow release structure, the situation that the fertility is too fast under the scouring of rainwater or irrigation water is avoided, the main reason of the slow release structure is also based on the viscosity of the clay, and under the action of rainwater or irrigation water, the viscosity of the clay ensures that other common fertilizers in the fertilizer core cannot be dissolved in water at one time, therefore, can ensure the lasting and long-term fertilizer efficiency. And with the continuous dissolution of other common fertilizers, the spherical particles of the fertilizer core become loose and porous and can be further used as a soil loosening material, and the spherical particles are completely crushed along with the passage of time, but the problem of soil caking cannot be caused due to the small clay consumption.
The preparation method of the soil testing formula fertilizer comprises the following steps:
(1) preparing a fertilizer core: preparing a fertilizer core raw material as required, wherein the mass of clay accounts for 8-10% of the total mass of the fertilizer core, and other common fertilizers are prepared according to the soil requirement; spraying water mist on the prepared raw materials under the stirring condition, uniformly mixing, forming and drying to obtain spherical fertilizer cores with the diameter of 2-3 mm;
(2) preparing a coating layer solution: dissolving PHA in chloroform at 90 ℃ to obtain PHA solution, wherein the concentration of PHA is 8-10g/L, and then dispersing PVA particles into the PHA solution to obtain a mixed system containing PHA and PVA, wherein the particle size of the PVA particles is 200-500 mu m; the mass ratio of PHA to PVA is 6: 4;
(3) preparing a soil testing formula fertilizer: and (3) spraying the mixed system obtained in the step (2) on the surface of the spherical fertilizer core obtained in the step (1), and drying to evaporate the solvent.
In the scheme, in the process of preparing the fertilizer core, water mist is sprayed to moisten the raw materials, so that the raw materials are conveniently bonded together by the clay, but the sprayed water mist is not too much, the clay is preferably just moistened, and the loss of other common fertilizers is easily caused by too much sprayed water mist; in the step (2), PVA particles are uniformly dispersed in the PHA solution, so that the problem that the PVA particles in the coating layer of the obtained soil testing formula fertilizer are not uniformly distributed is avoided. The method comprises the steps of preparing a film stock solution of a coating layer by utilizing the property that PHA is soluble in chloroform and PVA is insoluble in chloroform, spraying the film stock solution on the surface of a fertilizer core, drying the fertilizer core, evaporating chloroform, coating PHA film on the surface of the fertilizer core, embedding PVA particles on the PHA film, dissolving PVA in water in the use process, forming a plurality of holes on the PHA film, and dissolving substances in the fertilizer core inside the coating layer out of the holes.
Soil one
(1) Preparing a fertilizer core: 40% of urea, 15% of potassium sulfate, 25% of monoammonium phosphate, 12% of calcium superphosphate, 8% of clay and other raw materials are prepared according to the soil requirement; spraying water mist on the prepared raw materials under the stirring condition, uniformly mixing, forming and drying to obtain spherical fertilizer cores with the diameter of 2-3 mm;
(2) preparing a coating layer solution: dissolving PHA in chloroform at 90 ℃ to obtain PHA solution, wherein the concentration of PHA is 8g/L, and then dispersing PVA particles into the PHA solution to obtain a mixed system containing PHA and PVA, wherein the particle size of the PVA particles is 200-500 mu m; the mass ratio of PHA to PVA is 6: 4;
(3) preparing a soil testing formula fertilizer: and (3) spraying the mixed system obtained in the step (2) on the surface of the spherical fertilizer core obtained in the step (1), drying and evaporating the solvent to form a film with the thickness of not more than 0.5mm on the surface of the fertilizer core, wherein countless PVA particles are embedded in the film.
When the soil testing formula fertilizer is used, a groove with the length of about 5cm is dug, and the obtained soil testing formula fertilizer is buried in the groove.
Soil II
(1) Preparing a fertilizer core: 24% of urea, 13% of ammonium sulfate, 27% of potassium sulfate, 17% of calcium nitrate, 10% of calcium magnesium phosphate fertilizer and 9% of clay; spraying water mist on the prepared raw materials under the stirring condition, uniformly mixing, forming and drying to obtain spherical fertilizer cores with the diameter of 2-3 mm;
(2) preparing a coating layer solution: dissolving PHA in chloroform at 90 ℃ to obtain PHA solution, wherein the concentration of PHA is 9g/L, and then dispersing PVA particles into the PHA solution to obtain a mixed system containing PHA and PVA, wherein the particle size of the PVA particles is 200-500 mu m; the mass ratio of PHA to PVA is 6: 4;
(3) preparing a soil testing formula fertilizer: and (3) spraying the mixed system obtained in the step (2) on the surface of the spherical fertilizer core obtained in the step (1), drying and evaporating the solvent to form a film with the thickness of not more than 0.5mm on the surface of the fertilizer core, wherein countless PVA particles are embedded in the film.
When the soil testing formula fertilizer is used, a groove with the length of about 5cm is dug, and the obtained soil testing formula fertilizer is buried in the groove.
Soil III
(1) Preparing a fertilizer core: 20% of urea, 19% of monoammonium phosphate, 15% of potassium chloride, 13% of zinc sulfate, 12% of magnesium sulfate, 11% of calcium superphosphate and 10% of clay; spraying water mist on the prepared raw materials under the stirring condition, uniformly mixing, forming and drying to obtain spherical fertilizer cores with the diameter of 2-3 mm;
(2) preparing a coating layer solution: dissolving PHA in chloroform at 90 ℃ to obtain PHA solution, wherein the concentration of PHA is 10g/L, and then dispersing PVA particles into the PHA solution to obtain a mixed system containing PHA and PVA, wherein the particle size of the PVA particles is 200-500 mu m; the mass ratio of PHA to PVA is 6: 4;
(3) preparing a soil testing formula fertilizer: and (3) spraying the mixed system obtained in the step (2) on the surface of the spherical fertilizer core obtained in the step (1), drying and evaporating the solvent to form a film with the thickness of not more than 0.5mm on the surface of the fertilizer core, wherein countless PVA particles are embedded in the film.
When the soil testing formula fertilizer is used, a groove with the length of about 5cm is dug, and the obtained soil testing formula fertilizer is buried in the groove.
Claims (6)
1. The soil testing formula fertilizer is characterized by comprising a fertilizer core and a coating layer coated on the surface of the fertilizer core, wherein the fertilizer core is in a spherical shape with the diameter of 2-3mm, the thickness of the coating layer is not more than 0.5mm, the raw material of the fertilizer core comprises clay accounting for 8-10% of the total mass of the fertilizer core, the coating layer is made of PHA and PVA, and the preparation method of the coating layer is as follows: dissolving PHA in heated chloroform to form PHA solution, dispersing PVA grains in PHA solution, spraying the obtained mixed system on the surface of fertilizer core, and forming a coating layer on the surface of fertilizer core after the chloroform is volatilized.
2. The preparation method of the soil testing formula fertilizer is characterized by comprising the following steps of:
(1) preparing a fertilizer core: preparing a fertilizer core raw material as required, wherein the mass of clay accounts for 8-10% of the total mass of the fertilizer core, and other common fertilizers are prepared according to the soil requirement; spraying water mist on the prepared raw materials under the stirring condition, uniformly mixing, forming and drying to obtain spherical fertilizer cores with the diameter of 2-3 mm;
(2) preparing a coating layer solution: dissolving PHA in heated chloroform to obtain PHA solution, and dispersing PVA grains into the PHA solution to obtain a mixed system containing PHA and PVA;
(3) preparing a soil testing formula fertilizer: and (3) spraying the mixed system obtained in the step (2) on the surface of the spherical fertilizer core obtained in the step (1), and drying to evaporate the solvent.
3. The method for preparing a soil testing formula fertilizer as claimed in claim 2, wherein the particle size of the PVA grains is 200-500 μm.
4. The method for preparing soil testing formula fertilizer according to claim 3, wherein the concentration of PHA in PHA solution is 8-10 g/L.
5. The method for preparing soil testing formula fertilizer according to claim 3, wherein the mass ratio of PHA and PVA is 6: 4.
6. The method for preparing the soil testing formula fertilizer according to claim 2, wherein the temperature of chloroform is 90 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011603619.3A CN112592233A (en) | 2020-12-30 | 2020-12-30 | Soil testing formula fertilizer and preparation method thereof |
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| CN202011603619.3A CN112592233A (en) | 2020-12-30 | 2020-12-30 | Soil testing formula fertilizer and preparation method thereof |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101372434A (en) * | 2008-09-24 | 2009-02-25 | 山东金正大生态工程股份有限公司 | Water-soluble resin coated controlled release fertilizer with polyethylene film as basecoat and preparation technique thereof |
| CN110950719A (en) * | 2019-10-29 | 2020-04-03 | 北京城市排水集团有限责任公司 | Coated controlled release fertilizer and preparation method thereof |
| CN111848292A (en) * | 2020-07-13 | 2020-10-30 | 上海大学 | Urea slow-release compound fertilizer and preparation method thereof |
-
2020
- 2020-12-30 CN CN202011603619.3A patent/CN112592233A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101372434A (en) * | 2008-09-24 | 2009-02-25 | 山东金正大生态工程股份有限公司 | Water-soluble resin coated controlled release fertilizer with polyethylene film as basecoat and preparation technique thereof |
| CN110950719A (en) * | 2019-10-29 | 2020-04-03 | 北京城市排水集团有限责任公司 | Coated controlled release fertilizer and preparation method thereof |
| CN111848292A (en) * | 2020-07-13 | 2020-10-30 | 上海大学 | Urea slow-release compound fertilizer and preparation method thereof |
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Application publication date: 20210402 |