1. An organic slow release fertilizer based on mushroom bran humic acid and attapulgite clay is characterized in that: the preparation method comprises the following steps:

s1 purification of Attapulgite Clay

Crushing attapulgite to 150-200 meshes, adding the crushed attapulgite into a sodium pyrophosphate solution with the mass concentration of 2.0%, stirring at a high speed until the attapulgite and the sodium pyrophosphate solution are uniformly mixed, heating to 40 ℃, continuously stirring for 1.5 hours, standing for layering, and extracting an upper-layer suspension;

adding a proper amount of H into the upper suspension₃PO₄After the reaction is carried out until no bubbles escape, carrying out ultrasonic dispersion for 30min, vigorously stirring for 5h, aging for 24h at room temperature, and carrying out centrifugal separationDiscarding the supernatant, collecting the lower solid, oven drying at 100 deg.C to obtain purified attapulgite clay, grinding, and sieving with 200 mesh sieve;

s2 extraction and conversion of humic acid carried in fermentation fungus chaff

Weighing a proper amount of deionized water and ultrasonically gelatinized fermentation fungus chaff, placing the deionized water and ultrasonically gelatinized fermentation fungus chaff into a conical flask, adding 10g/L NaOH solution, adjusting the pH = 8-9, placing the conical flask into a constant-temperature oscillation box at 80 ℃ for oscillation for 12h, carrying out vacuum filtration, completely washing residues in the conical flask onto a filter membrane, carrying out centrifugal separation on collected filtrate to remove supernatant, collecting lower-layer solids, drying at 100-150 ℃, and crushing through a 150-200-mesh screen to obtain sodium humate;

s3, preparation of compound fertilizer:

mixing attapulgite and sodium humate according to a certain proportion, placing the mixture in a ball mill, carrying out ball milling for 2 hours at a rotating speed of 400-600 r/min, and sieving to obtain the compound fertilizer.

2. The organic slow-release fertilizer based on mushroom bran humic acid and attapulgite clay according to claim 1, which is characterized in that: the fermentation fungus chaff is one or a mixture of a plurality of fermentation fungus chaffs left after fruiting of shiitake mushrooms, oyster mushrooms, pleurotus cornucopiae, agaricus bisporus, pleurotus eryngii, agrocybe cylindracea, flammulina velutipes, pleurotus citrinopileatus, hypsizygus marmoreus, black fungi and lyophyllum decastes.

3. The organic slow-release fertilizer based on mushroom bran humic acid and attapulgite clay according to claim 1, which is characterized in that: in the step S2, 40-60 parts of deionized water and 10-20 parts of ultrasonically gelatinized fermentation fungus chaff are respectively weighed in parts by weight and placed in a conical flask, 10g/L of NaOH solution is added, the mixture is placed in a constant-temperature oscillation box at 80 ℃ for oscillation for 12 hours, and a product is taken out, subjected to vacuum filtration and dried to obtain the sodium humate.

4. The organic slow-release fertilizer based on mushroom bran humic acid and attapulgite clay according to claim 1, which is characterized in that: in the step S3, 40-50 parts of sodium humate and attapulgite are mixed according to the following proportion: mixing 25 percent to 75 percent, 50 percent to 50 percent and 75 percent to 25 percent, respectively putting the mixture into a ball mill, ball-milling the mixture for 2 hours at the rotating speed of 400-600 r/min, and then sieving the ground sample by a standard sieve of 200 meshes to obtain the compound fertilizer with different proportions.

5. The organic slow-release fertilizer based on mushroom bran humic acid and attapulgite clay according to claim 1, which is characterized in that: the mass ratio of the attapulgite to the sodium humate is 1: 3.

6. The organic slow-release fertilizer based on mushroom bran humic acid and attapulgite clay according to claim 1, which is characterized in that: the nutrient substance of the organic slow-release fertilizer is humic acid, the content of the humic acid accounts for 18-63% of that of the compound fertilizer, and the humic acid can be slowly released.

Background

In the current market, common humic acid fertilizers are quick-acting fertilizers and have very limited action time. If rainwater or irrigation exists, fertilizer in soil can be dissolved into water and flows into rivers and underground water, which not only wastes resources, but also seriously pollutes the ecological environment. As a big agricultural country, a large amount of fertilizer is required in agricultural production every year. However, in the agricultural production aspect, research on slow release fertilizers is a new direction in recent years, and the research on the slow release fertilizers can save resources and protect the environment.

The fermentation fungus chaff contains various microorganisms and nutrient substances, contains more humic acid, has higher utilization value, can directly participate in the metabolic process of substances, can improve the activity of a few enzymes in crops, and is necessary nutrient for the normal growth of the crops. The loss of humic acid can slow plant growth, resulting in reduced yield and quality of the crop. After humic acid is extracted from the fermentation mushroom bran, the humic acid and attapulgite are prepared into the compound fertilizer, which is beneficial to improving the micropore structure in soil and maintaining the physicochemical property of the fertilizer and can also improve the soil function.

The attapulgite mainly contains water magnesium aluminum silicate, has special physical and chemical properties, has the capacities of adsorption, selectivity, cation exchange and the like, and can improve the performance of soil so as to improve the water storage and fertilizer retention capacity of the soil. The attapulgite contains various mineral nutrient elements and trace elements, and the yield of crops can be improved by independently mixing the attapulgite with soil. For a single fertilizer, after attapulgite is added, the absorption characteristic of the attapulgite can play a role in slow release and control on the fertilizer, thereby reducing the loss rate of the fertilizer, prolonging the acting time of the fertilizer on crops, improving the yield and obviously improving the yield of agricultural products.

Humic acid is a natural organic polymer, which is accumulated in a slow chemical process through a series of microbial decomposition, transformation, synthesis, and is widely present in soil, coal, peat, and water. The humic acid is a complex mixture, is applied to various fields of chemical industry, agriculture, forestry, animal husbandry, petroleum, medicine, sanitation, environmental protection and the like, and can activate soil, has synergistic and synergistic effects on phosphorus and has a certain slow release effect on nitrogen and potassium. Humic acid is mainly used for activating fixed phosphorus elements in soil, improving the supply level of phosphorus in the soil and slowly releasing nutrient substances containing N, P, K and the like in a complex state, so that the problems of the saturation characteristic of the fertilizer and short-term insufficient fertilizer supply are solved, the release of nutrients is effectively controlled, the nutrient supply period is prolonged, the nutrient substances are better supplied to crops, the utilization rate of the fertilizer is improved, and the yield and the quality of the crops are increased.

Disclosure of Invention

In order to solve the problems, the invention provides an organic slow-release fertilizer based on mushroom bran humic acid and attapulgite clay, which takes attapulgite as a carrier, and is prepared by blending the attapulgite with sodium humate after being mechanically processed by a physical method.

In order to achieve the purpose, the invention adopts the technical scheme that:

an organic slow release fertilizer based on mushroom bran humic acid and attapulgite clay is prepared by the following steps:

s1 purification of Attapulgite Clay

S11, feeding attapulgite raw soil into a pulverizer to be pulverized and sieving to prepare clay powder of 150-200 meshes;

s12, adding the attapulgite clay powder into a sodium pyrophosphate solution with the mass concentration of 2.0%, and stirring at high speed to mix uniformly. Then the temperature is raised to 40 DEGStirring for 1.5 hr, standing for layering, collecting upper suspension, and adding appropriate amount of H₃PO₄Reacting until no bubbles escape;

s13, ultrasonically dispersing the suspension for 30min, strongly stirring for 5h, aging at room temperature for 24h, centrifuging by using a high-speed centrifuge, removing supernatant, and collecting lower-layer solid. Drying in oven at 100 deg.C, grinding, and sieving with 200 mesh sieve;

s2 extraction and conversion of humic acid carried in fermentation fungus chaff

Weighing 40-60 parts by weight of deionized water and 10-20 parts by weight of ultrasonically gelatinized fermentation fungus chaff respectively, placing the deionized water and 10-20 parts by weight of ultrasonically gelatinized fermentation fungus chaff into a conical flask, adding 10g/L NaOH solution, adjusting the pH to be = 8-9, placing the conical flask into a constant-temperature oscillation box at 80 ℃ for oscillation for 12 hours, carrying out vacuum filtration, washing all residues in the conical flask onto a filter membrane, carrying out centrifugal separation on collected filtrate to remove supernatant, collecting lower-layer solids, drying the lower-layer solids at 100-150 ℃, and crushing the lower-layer solids through a screen mesh of 150-200 meshes to obtain sodium humate;

s3, preparation of compound fertilizer:

40-50 parts of sodium humate and attapulgite are mixed according to the following proportion: mixing 25 percent to 75 percent, 50 percent to 50 percent and 75 percent to 25 percent, respectively putting the mixture into a ball mill, ball-milling the mixture for 2 hours at the rotating speed of 400-600 r/min, and then sieving the ground sample by a standard sieve of 200 meshes to obtain the compound fertilizer with different proportions.

Further, the fermentation fungus chaff is one or a mixture of a plurality of fermentation fungus chaffs left after fruiting of edible fungi such as shiitake mushrooms, oyster mushrooms, pleurotus cornucopiae, agaricus bisporus, pleurotus eryngii, agrocybe cylindracea, flammulina velutipes, pleurotus citrinopileatus, hypsizygus marmoreus, black fungus, lyophyllum decastes and the like.

Further, the mass ratio of the attapulgite to the sodium humate is 1: 3.

Furthermore, the nutrient substance of the organic slow-release fertilizer is humic acid, the content of the humic acid accounts for about 18-63% of that of the compound fertilizer, and the humic acid can be slowly released.

Further, to avoid overheating during ball milling, all experimental details were conducted by alternating 30min ball milling and 25 min rest during ball milling.

The invention has the following beneficial effects:

the novel compound fertilizer prepared by the ball milling method has the advantages of yield increase, quality improvement, soil improvement and good effect on slow release of nutrient substances, is easier to store than a single humic acid fertilizer, is not easy to agglomerate, is favorable for slow release of nutrient components, and can be efficiently absorbed by crops.

The organic slow-release fertilizer can promote plant growth, improve fertilizer efficiency, utilization rate of soil organic matters and the like, regulate porosity of soil, enhance soil fertilizer retention and nutrient supply capacity and the like by improving the structure of the soil. During the use of the humic acid compound fertilizer, the pollution to the environment and soil to a certain extent caused by excessive fertilizer input can be reduced or reduced, so that the production of green agricultural products is more favorably realized, and the ecological and social benefits are greatly increased.

Drawings

FIG. 1 is a Scanning Electron Microscope (SEM) photograph of an organic slow release fertilizer based on mushroom bran humic acid and attapulgite clay;

FIG. 2 is an infrared spectrogram of an organic slow-release fertilizer based on mushroom bran humic acid and attapulgite clay;

FIG. 3 is an X-ray diffraction diagram of the organic slow-release fertilizer based on the mushroom bran humic acid and the attapulgite clay;

FIG. 4 is a slow release rate curve diagram of an organic slow release fertilizer based on mushroom bran humic acid and attapulgite clay;

FIG. 5 is a diagram showing the growth analysis of cultivated crop (capsicum frutescens) without slow release fertilizer and with organic slow release fertilizer.

Detailed Description

In order that the objects and advantages of the invention will be more clearly understood, the invention is further described in detail below with reference to examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example 1

(1) Sending attapulgite raw soil into a pulverizer to be pulverized and sieving to obtain 150-mesh clay powder;

(2) adding the attapulgite clay powder into a sodium pyrophosphate solution with the mass concentration of 2.0%, and stirring at a high speed until the attapulgite clay powder and the sodium pyrophosphate solution are uniformly mixed. Then heating to 40 ℃, continuing stirring for 1.5H, standing for layering, extracting upper suspension, and adding a proper amount of H₃PO₄Reacting until no bubbles escape;

(3) and (3) ultrasonically dispersing the suspension for 30min, strongly stirring for 5h, aging at room temperature for 24h, centrifuging by using a high-speed centrifuge, removing supernatant, and collecting lower-layer solid. Drying in oven at 100 deg.C, grinding, and sieving with 200 mesh sieve;

(4) respectively weighing 40 parts by weight of deionized water and 10 parts by weight of ultrasonically gelatinized fermentation fungus chaff in a conical flask, adding NaOH solution, placing in a constant-temperature oscillating box at 80 ℃ for oscillating for 12 hours, taking out a product, performing vacuum filtration, and drying to obtain sodium humate;

(5) 40 parts of sodium humate and attapulgite are mixed according to the following proportion: mixing 25 percent to 75 percent, 50 percent to 50 percent and 75 percent to 25 percent, respectively putting the mixture into a ball mill, ball-milling the mixture for 2 hours at the rotating speed of 400 r/min, and then sieving the ground sample by a standard sieve of 200 meshes to obtain the compound fertilizer with different proportions.

(6) And drying the obtained compound fertilizer, screening, and packaging the screened qualified fertilizer.

And (3) performance detection:

the compound fertilizer is characterized by utilizing a Scanning Electron Microscope (SEM), and ATP-C can be seen₉H₈Na₂O₄(1: 3) are agglomerated together, and no layering or non-uniformity phenomenon exists, which shows that the sodium humate and the attapulgite are uniformly blended after ball milling, so that a substance effect is achieved, and the mechanical and chemical process can enable the sodium humate and the attapulgite to be efficiently compounded to exert the optimal effect and application.

3615 cm can be known by infrared absorption spectrum characterization^-1The left and right are-OH vibration of Mg and Al between octahedron and tetrahedron in the internal structure of ATP; 3423 cm^-1The weak absorption peaks at the left and right are the absorption of H in the internal structure₂O-OH vibration; 1639 cm^-1The weak absorption peaks at the left and right are ATP surface and interlaminar H₂O-OH vibration, 1416 cm^-1The left and right absorption peaks belong to characteristic absorption peaks of carbonate impurities; 977 cm^-1The vibration absorption of Si-O-Si in ATP is carried out on the left and the right; 900 cm^-1The following absorption peaks are the vibrational absorption of other metals in ATP. At 2930 cm^-1、2850 cm^-1Nearby is-CH₂Symmetric and antisymmetric telescopic vibrations. 1650 cm^-1At the absorption peak caused by C = C vibration, 1450 cm^-1Where is the absorption peak of C = O vibration, 1000cm^-1It is the absorption peak of C-O vibration, which is the characteristic absorption peak of sodium humate. For ATP-C₉H₈Na₂O₄977 cm of infrared absorption curve^-1The part obviously has a characteristic absorption peak of ATP, and the rest is an absorption peak of sodium humate, wherein ATP-C₉H₈Na₂O₄(1: 3) spectrum and C₉H₈Na₂O₄Most similar. Fourier infrared spectrum results show that compared with pure substances, the infrared spectrum of the corresponding compound fertilizer does not have a new absorption peak, so that the organic slow-release fertilizer is proved to have no new chemical bond, and the absorption peak position, ATP and C are proved to be connected₉H₈Na₂O₄The peak positions of the compounds are basically consistent, which shows that the formation of the compound fertilizer is not chemical interaction but only physical interaction, and is regarded as a simple mechanochemical process. Meanwhile, the mechanical and chemical process is also shown to be capable of efficiently compounding the sodium humate and the attapulgite.

Characterization by X-ray diffraction gave: as can be seen from the X-ray spectrum of ATP, characteristic diffraction peaks of ATP appeared at 2 θ =21 ° and 26.7 °. As can be seen from the figure, C₉H₈Na₂O₄A broad diffraction peak appears around 2 θ =20 °, and a peak appears around 2 θ =27 °, which are characteristic absorption peaks of sodium humate, indicating that sodium humate is an amorphous particle. At ATP-C₉H₈Na₂O₄In the X-ray diffraction of (1: 3), relatively dispersed absorption peaks appear between 20 theta and 27 theta, which is caused by C₉H₈Na₂O₄After ball milling with ATP, C₉H₈Na₂O₄Complete insertion into ATP, disorganized. ATP-C₉H₈Na₂O₄(1: 1) and ATP-C₉H₈Na₂O₄The characteristic absorption peak of (3: 1) is not much different from that of ATP, because the content of sodium humate is low, which results in complete coating by ATP after ball milling, and thus only ATP characteristic absorption peak is shown. Thus, ATP-C was shown₉H₈Na₂O₄The preparation ratio of the compound fertilizer is 1:3, and the effect of the compound fertilizer in application is optimal.

The slow release rate of the compound fertilizer is determined according to the following method:

m g samples were weighed into a conical flask, 70 mL of 10g/L NaOH solution was added, and the mixture was shaken in an incubator at 80 ℃ for 12 hours. Suction filtration was performed by vacuum, and the residue in the flask was rinsed out onto the filter. Carefully rinsing the funnel wall of the glass filter with a small amount of deionized water, collecting the washing liquid in a volumetric flask, and then fixing the volume with the deionized water for measuring the content of humic acid.

Accurately transferring 5.00 mL of filtrate in the volumetric flask into a conical flask, adding 0.5 mL of potassium dichromate solution with the mass concentration of 0.8 mol/L, slowly adding 15 mL of concentrated sulfuric acid, and heating and oxidizing in a water bath at the temperature of 82-83 ℃ for 30 min. Taking the oxidized solution down from the water bath, cooling to room temperature, adding about 70 mL of water, adding 3 drops of a phenanthroline-ammonium ferrous sulfate mixed indicating solution, titrating by using a 0.25 mol/L ammonium ferrous sulfate standard titration solution, and simultaneously carrying out a blank test, wherein the solution is changed from orange to brick red through bright green.

And (4) calculating a result: content of humic acid

The method comprises the following steps: HG/T3276-2012 determines the slow release performance of humic acid in the organic slow release fertilizer based on the mushroom bran humic acid and the attapulgite clay.

The result is shown in figure 4, the prepared compound fertilizer has good slow release capacity, can be continuously and slowly released in pure water, the release amount and the time are in a linear increasing trend, the compound fertilizer tends to be stable after being continuously released for 10 days, the release rate can reach about 52% after 2 weeks, and the compound fertilizer has good slow release capacity.

Example 2

(1) Sending attapulgite raw soil into a pulverizer to be pulverized and sieving to obtain clay powder of 200 meshes;

(2) adding the attapulgite clay powder into a sodium pyrophosphate solution with the mass concentration of 2.0%, and stirring at a high speed until the attapulgite clay powder and the sodium pyrophosphate solution are uniformly mixed. Then heating to 40 ℃, continuing stirring for 1.5H, standing for layering, extracting upper suspension, and adding a proper amount of H₃PO₄Reacting until no bubbles escape;

(3) and (3) ultrasonically dispersing the suspension for 30min, strongly stirring for 5h, aging at room temperature for 24h, centrifuging by using a high-speed centrifuge, removing supernatant, and collecting lower-layer solid. Drying in oven at 100 deg.C, grinding, and sieving with 200 mesh sieve;

(4) respectively weighing 50 parts by weight of deionized water and 20 parts by weight of ultrasonically gelatinized fermentation fungus chaff in a conical flask, adding NaOH solution, placing in a constant-temperature oscillating box at 80 ℃ for oscillating for 12 hours, taking out a product, performing vacuum filtration, and drying to obtain sodium humate;

(5) 50 parts of sodium humate and attapulgite are mixed according to the following proportion: mixing 25 percent to 75 percent, 50 percent to 50 percent and 75 percent to 25 percent, respectively putting the mixture into a ball mill, ball-milling the mixture for 2 hours at the rotating speed of 440 r/min, and then sieving the ground sample by a 150-mesh standard sieve to obtain the compound fertilizer with different proportions.

(6) And drying the obtained compound fertilizer, screening, and packaging the screened qualified fertilizer.

Example 3

(1) Sending attapulgite raw soil into a pulverizer to be pulverized and sieving to obtain clay powder of 200 meshes.

(2) Adding the attapulgite clay powder into a sodium pyrophosphate solution with the mass concentration of 2.0%, and stirring at a high speed until the attapulgite clay powder and the sodium pyrophosphate solution are uniformly mixed. Then heating to 40 ℃, continuing stirring for 1.5H, standing for layering, extracting upper suspension, and adding a proper amount of H₃PO₄And reacting until no bubbles escape.

(3) And (3) ultrasonically dispersing the suspension for 30min, strongly stirring for 5h, aging at room temperature for 24h, centrifuging by using a high-speed centrifuge, removing supernatant, and collecting lower-layer solid. Drying in oven at 100 deg.C, grinding, and sieving with 200 mesh sieve.

(4) Respectively weighing 40 parts of deionized water and 20 parts of ultrasonically gelatinized fermentation fungus chaff in parts by weight, placing the deionized water and the ultrasonically gelatinized fermentation fungus chaff in a conical flask, adding a NaOH solution, placing the conical flask in a constant-temperature oscillating box at 80 ℃ for oscillating for 12 hours, taking out a product, carrying out vacuum filtration, and drying to obtain the sodium humate.

(5) 40 parts of sodium humate and attapulgite are mixed according to the following proportion: mixing 25 percent to 75 percent, 50 percent to 50 percent and 75 percent to 25 percent, respectively putting the mixture into a ball mill, ball-milling the mixture for 2 hours at the rotating speed of 440 r/min, and then sieving the ground sample by a standard sieve of 200 meshes to obtain the compound fertilizer with different proportions.

(6) And drying the obtained compound fertilizer, screening, and packaging the screened qualified fertilizer.

Example 4

(1) Sending attapulgite raw soil into a pulverizer to be pulverized and sieving to obtain 180-mesh clay powder.

(2) Adding the attapulgite clay powder into a sodium pyrophosphate solution with the mass concentration of 2.0%, and stirring at a high speed until the attapulgite clay powder and the sodium pyrophosphate solution are uniformly mixed. Then heating to 40 ℃, continuing stirring for 1.5H, standing for layering, extracting upper suspension, and adding a proper amount of H₃PO₄And reacting until no bubbles escape.

(3) And (3) ultrasonically dispersing the suspension for 30min, strongly stirring for 5h, aging at room temperature for 24h, centrifuging by using a high-speed centrifuge, removing supernatant, and collecting lower-layer solid. Drying in oven at 100 deg.C, grinding, and sieving with 200 mesh sieve.

(4) Respectively weighing 50 parts by weight of deionized water and 10 parts by weight of ultrasonically gelatinized fermentation fungus chaff in a conical flask, adding NaOH solution, placing in a constant-temperature oscillating box at 80 ℃ for oscillating for 12 hours, taking out a product, carrying out vacuum filtration, and drying to obtain the sodium humate.

(5) 50 parts of sodium humate and attapulgite are mixed according to the following proportion: mixing 25 percent to 75 percent, 50 percent to 50 percent and 75 percent to 25 percent, respectively putting the mixture into a ball mill, ball-milling the mixture for 2 hours at the rotating speed of 540 r/min, and then sieving the ground sample by a standard sieve of 200 meshes to obtain the compound fertilizer with different proportions.

(6) And drying the obtained compound fertilizer, screening, and packaging the screened qualified fertilizer.

Example 5

(1) Sending attapulgite raw soil into a pulverizer to be pulverized and sieving to obtain clay powder of 200 meshes.

(2) Adding the attapulgite clay powder into a sodium pyrophosphate solution with the mass concentration of 2.0%, and stirring at a high speed until the attapulgite clay powder and the sodium pyrophosphate solution are uniformly mixed. Then heating to 40 ℃, continuing stirring for 1.5H, standing for layering, extracting upper suspension, and adding a proper amount of H₃PO₄And reacting until no bubbles escape.

(3) And (3) ultrasonically dispersing the suspension for 30min, strongly stirring for 5h, aging at room temperature for 24h, centrifuging by using a high-speed centrifuge, removing supernatant, and collecting lower-layer solid. Drying in oven at 100 deg.C, grinding, and sieving with 200 mesh sieve.

(4) Respectively weighing 50 parts by weight of deionized water and 20 parts by weight of ultrasonically gelatinized fermentation fungus chaff in a conical flask, adding NaOH solution, placing in a constant-temperature oscillating box at 80 ℃ for oscillating for 12 hours, taking out a product, carrying out vacuum filtration, and drying to obtain the sodium humate.

(5) 50 parts of sodium humate and attapulgite are mixed according to the following proportion: mixing 25 percent to 75 percent, 50 percent to 50 percent and 75 percent to 25 percent, respectively putting the mixture into a ball mill, ball-milling the mixture for 2 hours at the rotating speed of 600 r/min, and then sieving the ground sample by a 150-mesh standard sieve to obtain the compound fertilizer with different proportions.

(6) And drying the obtained compound fertilizer, screening, and packaging the screened qualified fertilizer.

Example 6

(1) Sending attapulgite raw soil into a pulverizer to be pulverized and sieving to obtain 180-mesh clay powder.

(2) Adding the attapulgite clay powder into a sodium pyrophosphate solution with the mass concentration of 2.0%, and stirring at a high speed until the attapulgite clay powder and the sodium pyrophosphate solution are uniformly mixed. Then heating to 40 ℃, continuing stirring for 1.5h, and standingAfter layering, extracting the upper suspension, and adding appropriate amount of H₃PO₄And reacting until no bubbles escape.

(3) And (3) ultrasonically dispersing the suspension for 30min, strongly stirring for 5h, aging at room temperature for 24h, centrifuging by using a high-speed centrifuge, removing supernatant, and collecting lower-layer solid. Drying in oven at 100 deg.C, grinding, and sieving with 200 mesh sieve.

(4) Respectively weighing 40 parts of deionized water and 10 parts of ultrasonically gelatinized fermentation fungus chaff in parts by weight, placing the deionized water and the ultrasonically gelatinized fermentation fungus chaff in a conical flask, adding a NaOH solution, placing the conical flask in a constant-temperature oscillating box at 80 ℃ for oscillating for 12 hours, taking out a product, carrying out vacuum filtration, and drying to obtain the sodium humate.

(5) 40 parts of sodium humate and attapulgite are mixed according to the following proportion: mixing 25 percent to 75 percent, 50 percent to 50 percent and 75 percent to 25 percent, respectively putting the mixture into a ball mill, ball-milling the mixture for 2 hours at the rotating speed of 600 r/min, and then sieving the ground sample by a standard sieve of 200 meshes to obtain the compound fertilizer with different proportions.

(6) And drying the obtained compound fertilizer, screening, and packaging the screened qualified fertilizer.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be construed as the protection scope of the present invention.