Treatment method for preventing fertilizer from caking

Abstract

The invention relates to the technical field of fertilizers, and discloses a treatment method for preventing caking of a fertilizer, which comprises the following steps: firstly, coating the fertilizer with a polymer coating film to form the polymer coating film which can effectively prevent the fertilizer from absorbing moisture and reduce the possibility of moisture absorption of particles, so that the caking resistance of the fertilizer particles is effectively improved; in addition, the used humic acid and glucan are biodegradable high-molecular substances and can achieve a certain improvement effect on soil to a certain extent, secondly, the added anti-caking agent can reduce adhesion and caking among particles caused by moisture by reducing direct contact among the particles, absorbing a small amount of moisture and the like, and the soil conditioner has the advantages that the soil conditioner has a good anti-caking effect. The effect of preventing caking can be achieved by reducing the capillary adsorption capacity of moisture to the particles, and the sodium hexametaphosphate can play a good positive role in dispersing the particles, so that the agglomeration and caking phenomena among the fertilizer particles are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of fertilizers, and in particular to a treatment method for preventing fertilizers from agglomerating. Background Art

[0002] Compound fertilizer is a kind of fertilizer containing multiple nutrients. It is widely used in agricultural production because of its uniform nutrient distribution, high structural density, stable and lasting fertilizer effect. However, compound fertilizer is prone to caking during production, transportation and storage, which not only affects the quality of the fertilizer, but also reduces its use effect. The main reason for the caking phenomenon is that compound fertilizer easily absorbs moisture in the air during production and storage, resulting in a high moisture content in the fertilizer particles. Generally speaking, when the moisture content of the particles exceeds 2%, the fertilizer strength decreases and crystal bridge caking is easily formed. In addition, excessive packaging temperature is also an important factor leading to caking. When the packaging temperature is more than 10 degrees higher than room temperature, the high-temperature dissolved substances will crystallize and precipitate during the cooling process to form crystal bridges, resulting in adhesion between particles. In addition, during storage, sunlight, large temperature difference between day and night, repeated dissolution and crystallization of inorganic salts and other chemical reactions, as well as moisture absorption and double decomposition reactions caused by long storage time, will cause compound fertilizer to clump.

[0003] The disadvantages of compound fertilizer agglomeration cannot be ignored. First, agglomeration will reduce the utilization rate of fertilizer. Since agglomerated fertilizer is difficult to be absorbed by the root system, nutrients cannot be fully released, resulting in reduced fertilizer efficiency. Secondly, agglomerated fertilizer will slow down the release of nutrients, causing slow growth and development of crops, thereby affecting crop yields. In addition, agglomeration will also affect the fluidity of fertilizers, easily clogging the fertilizer holes of the seeder, causing inconvenience to mechanized fertilization. To this end, the present invention provides a method for preventing fertilizer agglomeration, which can solve the problems existing in the prior art. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the deficiencies of the prior art, the present invention provides a treatment method for preventing fertilizer from agglomerating.

[0006] (II) Technical solution

[0007] A method for preventing fertilizer from caking comprises the following steps:

[0008] Step 1: Mix the fertilizer and the polymer coating agent, mechanically stir and mix at a stirring rate of 1000-2000 r / min for 20-30 minutes to form a uniform mixture, and then use a spray dryer to spray dry to form a fertilizer coating powder;

[0009] Step 2: Add anti-caking agent to the fertilizer coating powder and mix evenly with mechanical stirring.

[0010] As a further embodiment of the present invention, in step one, the fertilizer is a compound fertilizer or a mixed fertilizer.

[0011] As a further embodiment of the present invention, in step 1, the preparation method of the polymer coating agent is as follows:

[0012] Step S1, performing anaerobic fermentation on soybeans to form soybean fermentation slurry, adding sodium humate and bran to the soybean fermentation slurry, stirring and mixing evenly to form a fermentation precursor, and then inoculating EM bacterial agent into the fermentation precursor, fermenting at room temperature for 15-25 days, stirring once every 1-2 days, drying the obtained material in a temperature environment of 40-50° C., grinding into powder, and obtaining a coating agent;

[0013] Step S2, dissolving dextran in water, stirring and mixing to form a uniform dextran solution, adding a coating agent and sodium tetraborate, and mechanically stirring to form a polymer coating agent.

[0014] As a further embodiment of the present invention, in step S1, the mass ratio of the soybean fermentation slurry, sodium humate, bran and EM bacterial agent is 1-2:10:3-5:0.01-0.02.

[0015] As a further solution of the present invention, in step S2, the mass fraction of the dextran solution is 20-30%.

[0016] As a further embodiment of the present invention, in step S2, the liquid-to-solid ratio of the dextran solution, the coating agent and the sodium tetraborate is 1 mL: 0.3-0.4 g: 0.1-0.2 g.

[0017] As a further solution of the present invention, in step 1, the air inlet temperature during spray drying is set at 170-180°C, the air outlet temperature is set at 80-90°C, and the feed rate is set at 10-15 L / h.

[0018] As a further scheme of the present invention, in step 2, the anti-caking agent is composed of light calcium, tricalcium phosphate, dispersant and sodium hexametaphosphate in a mass ratio of 1:0.5-1:0.3-0.5:0.3-0.5, and the mass of the anti-caking agent added is 3-5% of the fertilizer coating powder.

[0019] As a further embodiment of the present invention, the dispersant is talc or silicon dioxide.

[0020] (III) Beneficial technical effects

[0021] The main raw materials of the polymer coating film of the present invention are humic acid and glucan fermented by microorganisms as polymer coating agents to coat the fertilizer, wherein the humic acid fermented by microorganisms contains more active groups in its structure and can be cross-linked with glucan under the action of the cross-linking agent sodium tetraborate, thereby generating a polymer coating film with a bridging structure on the surface of the fertilizer. The existence of the coating film can effectively prevent the fertilizer from absorbing water and reduce the possibility of moisture absorption by the particles, thereby effectively improving the anti-caking property of the fertilizer particles. Moreover, the humic acid and glucan used are both biodegradable polymer substances, which can have a certain improvement effect on the soil to a certain extent.

[0022] The present invention adopts the addition of anti-caking agent, utilizes the special chemical properties of light calcium and tricalcium phosphate, fills between food particles, forms an isolation layer, reduces direct contact between particles, and thus reduces the risk of caking, and tricalcium phosphate has certain hygroscopicity, can absorb a small amount of water, and reduce the adhesion and caking between particles caused by water. Talcum powder has good hydrophobicity, can improve the water-increasing effect of particles, reduce the capillary adsorption force of water on particles, and achieve the effect of preventing caking, and sodium hexametaphosphate can play a good positive role in the dispersion of particles, thereby reducing the agglomeration and caking phenomenon between fertilizer particles. DETAILED DESCRIPTION

[0023] In order to facilitate the understanding of the present invention, the present invention will be described more fully below. Preferred embodiments of the present invention are given below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0024] Preparation Example 1

[0025] A method for preventing fertilizer from caking comprises the following steps:

[0026] Step 1: Mix 5g of compound fertilizer and 100g of polymer coating agent, mechanically stir and mix at a stirring rate of 1000r / min for 30min to form a uniform mixture, and then use a spray dryer for spray drying, setting the inlet air temperature to 170°C, the outlet air temperature to 80°C, and the feed rate to 10L / h to form a fertilizer coating powder;

[0027] Step 2: Add an anti-caking agent to the fertilizer coating powder formed in step 1, and mix evenly with mechanical stirring.

[0028] The preparation method of the polymer coating agent is as follows:

[0029] Step S1, performing anaerobic fermentation on soybeans to form soybean fermentation slurry, adding 10g of sodium humate and 3g of bran to 1g of soybean fermentation slurry, stirring and mixing to form a fermentation precursor, and then inoculating 0.01g of EM bacterial agent into the fermentation precursor, fermenting at room temperature for 15 days, stirring once every 1 day, drying the obtained material in a temperature environment of 45°C, grinding it into powder, and obtaining a coating agent;

[0030] Step S2, dissolving dextran in water, stirring and mixing to form 10 mL of a 20% dextran solution, adding 3 g of a coating agent and 1 g of sodium tetraborate, and mechanically stirring to form a polymer coating agent.

[0031] The anti-caking agent is composed of light calcium, tricalcium phosphate, talcum powder and sodium hexametaphosphate in a mass ratio of 1:0.5:0.3:0.3, and the mass of the anti-caking agent added is 3% of the fertilizer coating powder.

[0032] Example 2

[0033] A method for preventing fertilizer from caking comprises the following steps:

[0034] Step 1: Mix 5g of compound fertilizer and 100g of polymer coating agent, mechanically stir and mix at a stirring rate of 1500r / min for 25min to form a uniform mixture, and then use a spray dryer for spray drying, setting the inlet air temperature to 175°C, the outlet air temperature to 85°C, and the feed rate to 12L / h to form a fertilizer coating powder;

[0035] Step 2: Add an anti-caking agent to the fertilizer coating powder formed in step 1, and mix evenly with mechanical stirring.

[0036] The preparation method of the polymer coating agent is as follows:

[0037] Step S1, performing anaerobic fermentation on soybeans to form soybean fermentation slurry, adding 10g of sodium humate and 4g of bran to 1.5g of the soybean fermentation slurry, stirring and mixing to form a fermentation precursor, and then inoculating 0.01g of EM bacterial agent into the fermentation precursor, fermenting at room temperature for 20 days, stirring every 2 days, drying the obtained material in a temperature environment of 45°C, grinding it into powder, and obtaining a coating agent;

[0038] Step S2, dissolving dextran in water, stirring and mixing to form 10 mL of a dextran solution with a mass fraction of 24%, adding 3.5 g of a coating agent and 1.5 g of sodium tetraborate, and mechanically stirring to form a polymer coating agent.

[0039] The anti-caking agent is composed of light calcium, tricalcium phosphate, talcum powder and sodium hexametaphosphate in a mass ratio of 1:0.6:0.4:0.4, and the mass of the anti-caking agent added is 4% of the fertilizer coating powder.

[0040] Example 3

[0041] A method for preventing fertilizer from caking comprises the following steps:

[0042] Step 1: Mix 5g of compound fertilizer and 100g of polymer coating agent, mechanically stir and mix at a stirring rate of 1500r / min for 25min to form a uniform mixture, and then use a spray dryer for spray drying, setting the inlet air temperature to 175°C, the outlet air temperature to 85°C, and the feed rate to 12L / h to form a fertilizer coating powder;

[0043] Step 2: Add an anti-caking agent to the fertilizer coating powder formed in step 1, and mix evenly with mechanical stirring.

[0044] The preparation method of the polymer coating agent is as follows:

[0045] Step S1, performing anaerobic fermentation on soybeans to form soybean fermentation slurry, adding 10g of sodium humate and 4.5g of bran to 1.8g of soybean fermentation slurry, stirring and mixing to form a fermentation precursor, and then inoculating 0.02g of EM bacterial agent into the fermentation precursor, fermenting at room temperature for 20 days, stirring every 2 days, drying the obtained material in a temperature environment of 45°C, grinding into powder, and obtaining a coating agent;

[0046] Step S2, dissolving dextran in water, stirring and mixing to form 10 mL of a dextran solution with a mass fraction of 25%, adding 3.6 g of a coating agent and 1.8 g of sodium tetraborate, and mechanically stirring to form a polymer coating agent.

[0047] The anti-caking agent is composed of light calcium, tricalcium phosphate, talcum powder and sodium hexametaphosphate in a mass ratio of 1:0.8:0.4:0.4, and the mass of the anti-caking agent added is 4% of the fertilizer coating powder.

[0048] Example 4

[0049] A method for preventing fertilizer from caking comprises the following steps:

[0050] Step 1: Mix 5g of compound fertilizer and 100g of polymer coating agent, mechanically stir and mix at a stirring rate of 2000r / min for 20min to form a uniform mixture, and then use a spray dryer for spray drying, setting the inlet air temperature to 180°C, the outlet air temperature to 90°C, and the feed rate to 15L / h to form a fertilizer coating powder;

[0051] Step 2: Add an anti-caking agent to the fertilizer coating powder formed in step 1, and mix evenly with mechanical stirring.

[0052] The preparation method of the polymer coating agent is as follows:

[0053] Step S1, performing anaerobic fermentation on soybeans to form soybean fermentation slurry, adding 10g of sodium humate and 5g of bran to 2g of the soybean fermentation slurry, stirring and mixing evenly to form a fermentation precursor, and then inoculating 0.02g of EM bacterial agent into the fermentation precursor, fermenting at room temperature for 25 days, stirring every 2 days, drying the obtained material in a temperature environment of 45°C, grinding it into powder, and obtaining a coating agent;

[0054] Step S2, dissolving dextran in water, stirring and mixing to form 10 mL of a 30% dextran solution, adding 4 g of a coating agent and 2 g of sodium tetraborate, and mechanically stirring to form a polymer coating agent.

[0055] The anti-caking agent is composed of light calcium, tricalcium phosphate, talcum powder and sodium hexametaphosphate in a mass ratio of 1:1:0.5:0.5, and the mass of the anti-caking agent added is 5% of the fertilizer coating powder.

[0056] Comparative Example 1

[0057] A method for preventing fertilizer from caking comprises the following steps:

[0058] Mix 5g of compound fertilizer and 100g of polymer coating agent, mechanically stir and mix at a stirring rate of 1500r / min for 25min to form a uniform mixture, and then use a spray dryer for spray drying, setting the inlet air temperature to 175℃, the outlet air temperature to 85℃, and the feed rate to 12L / h to form a fertilizer coating powder.

[0059] The preparation method of the polymer coating agent is the same as that in Example 2.

[0060] Comparative Example 2

[0061] A method for preventing fertilizer from caking comprises the following steps:

[0062] Mix 5g of compound fertilizer and anti-caking agent evenly with mechanical stirring.

[0063] The preparation method of the anticaking agent is the same as that in Example 2.

[0064] Test Case

[0065] Take the fertilizer obtained by the treatment method in the embodiment and the comparative example, and conduct an experiment. The specific experimental method is as follows: place the fertilizer in a closed container, control the relative humidity in the container to 90±5%, and the temperature to 50±5°C, take out the fertilizer after 4 hours, dry it in an oven at 50°C, take it out when it is dried to a water content of 2%, and place it in a sealed bag of the same specification, then transfer the sealed bag to a temperature environment of 60°C and heat it for 4 hours before taking it out, wait for it to cool naturally, and cycle the process 3 times. During the treatment process, a 5-kilogram iron block is used to compact the sealed bag. After the treatment is completed, the sealed bag is horizontally free-fallen from a half-meter height to a hard plane, the compound fertilizer in the sealed bag is taken out, and the agglomerated and unagglomerated compound fertilizers are separated, weighed, and the agglomeration rate is calculated. The calculation formula is (mass of agglomerated compound fertilizer / total mass of compound fertilizer)×100%, and the demerits are recorded in the following table:

[0066] Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Agglomeration rate / % 0.31 0.28 0.29 0.34 0.61 0.73

[0067] Analysis shows that the anti-caking effect of compound fertilizer can be synergistically improved by coating the compound fertilizer and adding anti-caking agents.

[0068] Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas, including the best mode, and also enable any technician in the field to practice the present invention, including making and using any device or system, and implementing any combined method. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the present invention. The scope of patent protection of the present invention is defined by the claims and may include other embodiments that can be thought of by those skilled in the art. If these other embodiments have structural elements similar to the literal expression of the claims, or if they include equivalent structural elements that are not substantially different from the literal expression of the claims, then these other embodiments should also be included in the scope of the claims.

[0069] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preventing fertilizer from caking, characterized in that: The following steps are involved: Step 1: Mix the fertilizer and the polymer coating agent, mechanically stir and mix at a stirring rate of 1000-2000 r / min for 20-30 minutes to form a uniform mixture, and then use a spray dryer to spray dry to form a fertilizer coating powder; Step 2: Add anti-caking agent to the fertilizer coating powder and mix evenly with mechanical stirring.

2. A method for preventing fertilizer from caking according to claim 1, characterized in that: In step 1, the fertilizer is compound fertilizer or mixed fertilizer.

3. A method for preventing fertilizer from caking according to claim 1, characterized in that: In step 1, the preparation method of the polymer coating agent is as follows: Step S1, performing anaerobic fermentation on soybeans to form soybean fermentation slurry, adding sodium humate and bran to the soybean fermentation slurry, stirring and mixing evenly to form a fermentation precursor, and then inoculating EM bacterial agent into the fermentation precursor, fermenting at room temperature for 15-25 days, stirring once every 1-2 days, drying the obtained material in a temperature environment of 40-50° C., grinding into powder, and obtaining a coating agent; Step S2, dissolving dextran in water, stirring and mixing to form a uniform dextran solution, adding a coating agent and sodium tetraborate, and mechanically stirring to form a polymer coating agent.

4. A method for preventing fertilizer from caking according to claim 3, characterized in that: In step S1, the mass ratio of the soybean fermentation slurry, sodium humate, bran and EM bacterial agent is 1-2:10:3-5:0.01-0.

02.

5. A method for preventing fertilizer from caking according to claim 3, characterized in that: In step S2, the mass fraction of the dextran solution is 20-30%.

6. A method for preventing fertilizer from caking according to claim 3, characterized in that: In step S2, the liquid-to-solid ratio of the dextran solution, the coating agent and sodium tetraborate is 1 mL: 0.3-0.4 g: 0.1-0.2 g.

7. A method for preventing fertilizer from caking according to claim 1, characterized in that: In step 1, the air inlet temperature during spray drying is set at 170-180°C, the air outlet temperature is set at 80-90°C, and the feed rate is set at 10-15L / h.

8. A method for preventing fertilizer from caking according to claim 1, characterized in that: In step 2, the anti-caking agent is composed of light calcium, tricalcium phosphate, dispersant and sodium hexametaphosphate in a mass ratio of 1:0.5-1:0.3-0.5:0.3-0.5, and the mass of the anti-caking agent added is 3-5% of the fertilizer coating powder.

9. A method for preventing fertilizer from caking according to claim 8, characterized in that: The dispersant is talc or silicon dioxide.