A method for producing organic fertilizer by using livestock and poultry manure

Abstract

The application discloses a preparation method of organic fertilizer produced by using livestock and poultry manure in the field of fertilizer production, and comprises the following steps: S1, adding gamma-polyglutamic acid to livestock and poultry manure matrix, inoculating compound probiotics to carry out fermentation, filtering, and obtaining livestock and poultry manure matrix fermentation liquor; S2, mixing the livestock and poultry manure matrix fermentation liquor, microbial capsules, modified humic acid, activated biochar, urea, diammonium phosphate and trace elements, carrying out compost fermentation, obtaining mixed fermentation material, and carrying out granulation and steam curing to obtain livestock and poultry manure organic fertilizer. Through the mode of adding microbial capsules, modified humic acid and activated biochar, the technical effect of shortening the fermentation time is realized, the stability of the organic fertilizer is improved through the synergistic effect among the components, and the active components of the organic fertilizer are slowly released, so that the technical effects of slow release and long-acting fertilizer preservation are achieved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of fertilizer production, and particularly relates to a preparation method for producing organic fertilizer by using livestock and poultry manure. BACKGROUND

[0002] With the growth of global population and the development of agricultural production, the use amount of traditional chemical fertilizers and chemical pesticides is gradually increased, which leads to problems such as soil quality decline, agricultural product quality decline, environmental pollution and the like; therefore, finding a fertilizer to replace traditional chemical fertilizers has become an important task in current agricultural production.

[0003] Livestock and poultry manure is a kind of waste produced in agricultural production, which will cause environmental pollution if not treated, but if the livestock and poultry manure can be converted into organic fertilizer, not only the dependence on chemical fertilizers can be reduced, but also the problem of waste treatment can be solved, resource reuse can be realized, and environmental pollution can be reduced, soil quality can be improved, and agricultural product quality can be improved; therefore, the technology of producing organic fertilizer by using livestock and poultry manure has important significance and development prospect in current agricultural production.

[0004] However, the existing technology mainly has the following problems: 1. single livestock and poultry manure substrate composting fermentation, long fermentation time, easy to produce odor and harmful gas; 2. the organic fertilizer produced by using livestock and poultry manure has poor stability and low fertilizer efficiency; 3. the organic fertilizer produced by using livestock and poultry manure has no slow-release effect and needs to be fertilized multiple times. SUMMARY

[0005] In view of the above problems, the present application provides a preparation method for producing organic fertilizer by using livestock and poultry manure, in order to solve the problem of long fermentation time of single livestock and poultry manure substrate composting fermentation, the present application proposes a method of adding microbial capsules, modified humic acid and activated biochar, which realizes the technical effect of shortening the fermentation time, and the synergistic effect between the components improves the stability of the organic fertilizer, and the active components of the organic fertilizer are slowly released, achieving the technical effect of slow release and long-acting fertilizer preservation.

[0006] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows: the present application provides a preparation method for producing organic fertilizer by using livestock and poultry manure, which specifically comprises the following steps:

[0007] S1, remove impurities from livestock manure matrix, crush, pass through a 20 mesh sieve, spray calcium chloride aqueous solution while stirring the livestock manure matrix, stand for 3h, then rinse with tap water, dry at 50-60℃ until the moisture content is 50-55%, add gamma-polyglutamic acid, inoculate activated compound probiotics, adjust the pH to 5.0-7.0, place in a sealed fermentation tank for fermentation, the fermentation temperature is 30-34℃, the fermentation time is 3-5d, obtain the fermentation product, filter through an 80 mesh sieve, obtain the livestock manure matrix fermentation liquor;

[0008] S2, mix the livestock manure matrix fermentation liquor, microbial capsules, modified humic acid, activated biochar, urea, diammonium phosphate, trace elements, stir until uniform, add water to adjust the moisture content to 50-60% of the total material, control the temperature to 50-60℃, carry out compost fermentation for 30 days, turn over every five days during the period, cool to 30-40℃, dry, obtain the mixed fermentation material;

[0009] S3, granulate the mixed fermentation material, the particle size is 1.5-4.5mm, obtain the pretreated livestock manure organic fertilizer;

[0010] S4, steam curing the pretreated livestock manure organic fertilizer, obtain the livestock manure organic fertilizer.

[0011] Preferably, in step S1, the livestock manure matrix includes at least one of cow dung, sheep dung, pig dung, and chicken dung;

[0012] Preferably, in step S1, the mass fraction of the calcium chloride aqueous solution is 2-3%;

[0013] Preferably, in step S1, the weight ratio of the livestock manure matrix to gamma-polyglutamic acid is 100:0.1-0.2;

[0014] Preferably, in step S1, the preparation method of the activated compound probiotics specifically includes the following steps: inoculate Trichoderma harzianum and Bacillus velezensis into Gause's culture medium for activation culture, the activation temperature is 28-32℃, the activation time is 2-3d, mix to obtain the activated compound probiotics;

[0015] Preferably, in step S1, the viable count of the Trichoderma harzianum is more than 1.5×10 8 CFU / g; the viable count of the Bacillus velezensis is more than 2.3×10 7 CFU / g;

[0016] Preferably, in step S1, the addition amount of the compound probiotics is 3-5% of the weight of the livestock manure matrix;

[0017] Preferably, in step S2, the trace elements include at least one of ferrous sulfate, manganese sulfate, zinc sulfate, manganese sulfate, copper sulfate pentahydrate, borax;

[0018] Preferably, in step S2, the weight ratio of the poultry manure-based fermentation liquid, the microbial capsules, the modified humic acid, the activated biochar, the urea, the diammonium phosphate, and the trace elements is 100:3-5:10-20:10-15:20-30:10-20:5-7;

[0019] Preferably, in step S4, the steam curing is placing the material in a steam curing box with a temperature of 80-100℃ and a relative humidity of 60-70%, and then increasing the temperature to 100-110℃ at a rate of 15-25℃ / h, and then steam curing for 8-12h;

[0020] Spraying the calcium chloride aqueous solution can help reduce the volatilization of ammonia in poultry manure, reduce the impact of odor on the surrounding environment, and help promote the microbial decomposition in the poultry manure fertilizer. Calcium chloride can also be used as a neutral salt to adjust the pH of the soil. Gamma-polyglutamic acid has good water retention performance, which can help increase the water and fertilizer retention capacity of the soil, and also provide nitrogen and carbon sources for plants, which is beneficial to the absorption and utilization of plants, thereby promoting the growth and development of plants.

[0021] Preferably, the preparation method of the microbial capsules specifically comprises the following steps:

[0022] (1) Dissolve carboxymethyl chitosan in a 2% acetic acid solution to obtain a carboxymethyl chitosan solution with a mass fraction of 1-2%; dissolve polyethylene glycol in distilled water and heat to 80-95℃ to completely dissolve it, obtaining a polyethylene glycol aqueous solution with a mass fraction of 3-6%; mix the carboxymethyl chitosan solution with the polyethylene glycol aqueous solution, add β-glycerophosphate sodium, heat to 60-80℃, and stir at a rate of 400-500 rpm for 1-1.5h, then cool to room temperature to obtain a shell solution;

[0023] (2) Mix the Trichoderma harzianum powder and Bacillus velezensis powder, add porous zeolite, and disperse in linoleic acid, then filter and dry to obtain a core material;

[0024] (3) Add the core material to the shell solution, stir uniformly, add glutaraldehyde, high-speed emulsify, and freeze-dry to obtain the microbial capsules.

[0025] Preferably, in step (1), the weight ratio of carboxymethyl chitosan, polyethylene glycol, and β-glycerophosphate sodium is 1-2:3-6:0.1-0.2;

[0026] Preferably, in step (2), the weight ratio of the Trichoderma harzianum powder, Bacillus velezensis powder, and porous zeolite is 1:1:4-6;

[0027] Preferably, in step (3), the weight ratio of the carboxymethyl chitosan and the crosslinking agent is 1:0.01-0.02;

[0028] Preferably, in step (3), the high-speed emulsification is high-speed emulsification at a speed of 8000-12000 rpm for 5-10 min and homogenization 3 times at 30-50 MPa.

[0029] Preferably, the preparation method of the modified humic acid specifically comprises the following steps:

[0030] ① Place the humic acid in a muffle furnace, blow it with an argon atmosphere at an air flow rate of 0.1-0.2 L / min, and maintain a heating rate of 15-20 ℃ / min, heat to a temperature of 500-800 ℃, calcine for 1-2 h, cool to room temperature, wash with a 10-15% hydrochloric acid solution, and dry in a constant temperature oven at 100 ℃ for 2-3 h to obtain pretreated humic acid;

[0031] ② Disperse the pretreated humic acid obtained in step ① in 100 mL N,N-methylenebisacrylamide, add polyacrylamide, stir and mix uniformly, add an initiator and a crosslinking agent, heat to 80-100 ℃, react for 3-5 h, cool to room temperature, wash with a 90-95% ethanol solution, and dry to obtain modified humic acid.

[0032] Preferably, in step ②, the weight ratio of the humic acid, polyacrylamide, initiator, and crosslinking agent is 10-20:4-12:0.1-0.2:0.4-1;

[0033] Preferably, in step ②, the initiator includes at least one of N,N'-dimethylethylenediamine, triethylamine, and hexanediamine;

[0034] Preferably, in step ②, the crosslinking agent includes at least one of glutaraldehyde, polyvinyl alcohol, and glycerol.

[0035] Preferably, the preparation method of the activated biochar specifically comprises the following steps:

[0036] A. Wash, dry, and pulverize the biomass, pass it through a 100-mesh sieve, add a pore-forming activator, mix evenly, place it in a muffle furnace, purge it under an argon atmosphere with a gas flow rate of 0.1-0.2 L / min, and maintain a heating rate of 10-20℃ / min, heat it to a temperature of 400-700℃, calcine for 1-2 hours, cool it to room temperature, soak it in a 30-35% acetic acid solution for 4-6 hours, wash it with deionized water until the pH is 6.0-7.0, and dry it in an 80℃ constant temperature drying oven for 1-2 hours to obtain pretreated biochar;

[0037] B. Immerse the pretreated biochar in Fe 3+ and Fe 2+ In the mixed solution, ultrasonic treatment was carried out for 30-40 minutes at a power of 100-300W and a temperature of 40-50℃. The mixture was then centrifuged at a speed of 8000-10000r / min for 1-2 hours. The solid was collected, washed with deionized water until the pH reached 6.8-7.2, and dried in a vacuum drying oven at a vacuum degree of 50-70Pa and a temperature of 80-90℃ for 2-3 hours to obtain activated biochar.

[0038] Preferably, in step A, the biomass is one or a mixture of several of the following: rice bran, wheat bran, soybean meal, and straw.

[0039] Preferably, in step A, the pore-forming activator includes at least one of potassium carbonate, potassium hydroxide, and calcium phosphate;

[0040] Preferably, in step A, the weight ratio of the biomass to the pore-forming activator is 10:0.1-0.3;

[0041] Preferably, in step B, the trivalent iron salt includes any one of Fe2(SO4)3, Fe(NO3)3, and FeCl3;

[0042] Preferably, in step B, the divalent iron salt includes any one of FeSO4, Fe(NO3)2, and FeCl2.

[0043] The beneficial effects achieved by this invention are as follows:

[0044] 1. This invention utilizes Trichoderma harzianum powder and Bacillus vesiculosus powder, which work synergistically to achieve highly effective antibacterial and pest-repelling effects. Trichoderma harzianum can produce antibiotics to inhibit the growth of pathogens and pests in the soil, decompose organic matter to release nutrients needed by plants, and secrete growth hormones to promote plant growth and development. Bacillus vesiculosus can produce toxic proteins with strong insecticidal effects and minimal impact on non-target organisms, making it an environmentally friendly pesticide. It can also secrete active substances that activate the plant defense system, enhance crop immunity and disease resistance, and reduce or eliminate the harm of pathogens to plants. By adding porous zeolite as a carrier material to the microorganisms, on the one hand, the attachment sites for microorganisms are increased, facilitating their growth and reproduction; on the other hand, the fixation effect of the internal fertilizer granules is strengthened, preventing granule detachment during transportation and use, thereby effectively ensuring the fertilizer loading and slow release. Effects: Linoleic acid, a hydrophobic unsaturated fatty acid, forms a hydrophobic layer structure, repelling water molecules and preventing fertilizer granules from absorbing water, thereby improving the fertilizer's moisture resistance and water tolerance. Using a carboxymethyl chitosan solution modified with polyethylene glycol and sodium β-glycerophosphate as a shell material to encapsulate microorganisms improves their stability, thus enhancing the fertilizer's slow-release effect and long-term stability, and increasing fertilizer utilization. Carboxymethyl chitosan is biodegradable and an environmentally friendly coating material. Strong hydrogen bonds exist between the amino groups of carboxymethyl chitosan and the hydroxyl groups of polyethylene glycol, forming a tight cross-linked structure. This structure makes the three-dimensional network space of the carboxymethyl chitosan solution less prone to expansion during swelling, thereby increasing the mechanical properties and stability of the microbial capsules. Due to the larger pore size of the modified carboxymethyl chitosan, the addition of sodium β-glycerophosphate effectively slows down the release of microorganisms, thus achieving the technical effect of slow and controlled fertilizer release.

[0045] 2. This invention first calcines humic acid at high temperature to increase its surface area and porosity, thereby enhancing its adsorption performance. Secondly, it disperses humic acid in N,N-methylenebisacrylamide and adds polyacrylamide. Grafting occurs between the carboxyl groups of humic acid and the amino groups of polyacrylamide, forming stable soil aggregates through cross-linking with the polymer, improving soil structure. Simultaneously, the addition of hydrophilic side chains enhances the water retention of humic acid, helping to maintain soil moisture, reducing soil compaction, decreasing the degree of micronutrient fixation in the soil, and promoting the absorption of micronutrients by crops. Furthermore, the carboxyl groups, alcoholic hydroxyl groups, and phenolic hydroxyl groups within the humic acid molecule undergo adsorption, precipitation, ion exchange, and complexation with heavy metal cations, thus helping to remove heavy metal pollutants from the soil and improve the soil environment.

[0046] 3. This invention incorporates biochar, activated from rice bran, wheat bran, soybean meal, and straw, into the poultry and livestock manure fertilizer. This avoids the generation of large amounts of wastewater and odorous gases during composting fermentation of pure poultry and livestock manure, which can cause collapse of the fermentation pile and material adhesion. The biochar base undergoes high-temperature calcination and acetic acid soaking to remove surface impurities and oxides, while simultaneously expanding the pore structure of the biochar, increasing its specific surface area, and improving pollutant adsorption performance. Dissolving the pretreated biochar in a mixture of ferric and ferrous salts generates magnetic biochar. The carboxyl groups in the modified humic acid and the iron ions in the activated biochar can form coordinate bonds, resulting in a stable chelate that enhances the stability and mechanical properties of the organic fertilizer. Furthermore, the porous structure and large specific surface area of ​​the activated biochar provide a growth site for microorganisms, while the modified humic acid serves as a nutrient source for them. The interaction between the two promotes the growth and reproduction of beneficial bacteria, thereby enhancing fertilizer efficiency.

[0047] 4. This invention makes full use of livestock manure and waste materials such as rice bran, wheat bran, soybean meal, and straw, turning them into valuable resources, increasing the added value and utilization value of waste materials, which is conducive to protecting the ecological environment and conforms to the concept of sustainable development. The preparation method of this invention is simple and easy to implement, the raw materials are cheap and readily available, effectively reducing production costs and has high application prospects. Attached Figure Description

[0048] Figure 1 This is a 500x magnified electron microscope scan of the surface of the activated biochar prepared in Example 1 of the present invention.

[0049] Figure 2 The graph shows the stability results of the organic fertilizers prepared in Example 1 and Comparative Examples 1-4 of the present invention after being stored in different pH environments for 7 days.

[0050] Figure 3 The graph shows the cumulative release of nitrogen fertilizer nutrients from the organic fertilizer granules prepared in Examples 1-3 and Comparative Examples 1-4 of this invention.

[0051] Figure 4 The graph shows the effect of the organic fertilizers prepared in Example 1 and Comparative Examples 1-4 of this invention on the nutritional quality of Chinese cabbage.

[0052] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. Detailed Implementation

[0053] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0054] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those familiar to those skilled in the art. Furthermore, any methods and materials similar to or equivalent to those described herein may be applied to this invention. The preferred embodiments and materials described herein are for illustrative purposes only and do not limit the scope of this application.

[0055] Unless otherwise specified, the experimental methods used in the following examples are conventional methods; unless otherwise specified, the test materials and test strains used in the following examples were purchased from commercial channels; and all quantities are parts by weight.

[0056] The strains involved in this invention originate from the following sources:

[0057] Trichoderma harzianum, strain number: CICC 13056, purchased from China Industrial Microbial Culture Collection Center;

[0058] Bacillus velezensis, strain number: CICC 20519, purchased from the China Industrial Microbial Culture Collection Center.

[0059] Example 1

[0060] A method for producing organic fertilizer from livestock and poultry manure specifically includes the following steps:

[0061] S1. Remove impurities from 100 kg of poultry and livestock manure substrate, crush it, pass it through a 20-mesh sieve, spray it with a 2% calcium chloride aqueous solution while turning the poultry and livestock manure substrate, let it stand for 3 hours, then rinse it with tap water, dry it at 50℃ until the moisture content is 50%, add 0.1 kg of γ-polyglutamic acid, inoculate it with activated compound probiotics, adjust the pH to 5.0, place it in a sealed fermentation tank for fermentation at 30℃ for 3 days, obtain the fermentation product, filter it through an 80-mesh sieve to obtain poultry and livestock manure-based fermentation liquid;

[0062] S2. Mix 100kg of poultry and livestock manure-based fermentation liquid, 3kg of microbial capsules, 10kg of modified humic acid, 10kg of activated biochar, 20kg of urea, 10kg of diammonium phosphate, and 5kg of ferrous sulfate. Stir well, add water to adjust the moisture content to 50% of the total material, control the temperature at 50℃, and compost for 30 days. During this period, turn the pile every five days, cool it down to 30℃, and dry it to obtain the mixed fermented material.

[0063] S3. Granulate the mixed fermented material to obtain pretreated poultry and livestock manure organic fertilizer;

[0064] S4. Place the pretreated poultry and livestock manure organic fertilizer in a steam curing box with a temperature of 80℃ and a relative humidity of 60%, and heat it to 100℃ at a rate of 15℃ / h, and steam curing for 8 hours to obtain poultry and livestock manure organic fertilizer.

[0065] The preparation method of activated compound probiotics specifically includes the following steps: Trichoderma harzianum and Bacillus belye are inoculated into Gao's medium for activation culture at an activation temperature of 28°C for 2 days, and then mixed to obtain activated compound probiotics;

[0066] The preparation method of microbial capsules specifically includes the following steps:

[0067] (1) Dissolve 1 kg of carboxymethyl chitosan in 100 L of 2% acetic acid solution to obtain carboxymethyl chitosan solution; dissolve 3 kg of polyethylene glycol in 100 L of distilled water and heat to 80 °C to completely dissolve it to obtain polyethylene glycol aqueous solution; mix the carboxymethyl chitosan solution and polyethylene glycol aqueous solution, add 0.1 kg of β-glycerophosphate sodium, heat to 60 °C, stir at 400 rpm for 1 h, cool to room temperature to obtain shell material solution;

[0068] (2) Mix 1 kg of Trichoderma harzianum powder and 1 kg of Bacillus vesiculosus powder, add 4 kg of porous zeolite, disperse in linoleic acid, filter and dry to obtain core material;

[0069] (3) Add the core material to the shell material solution, stir evenly, add 0.01 kg of glutaraldehyde, emulsify at 8000 rpm for 5 min, homogenize 3 times at 30 MPa, freeze dry to obtain microbial capsules.

[0070] The preparation method of modified humic acid specifically includes the following steps:

[0071] ① Place 10 kg of humic acid in a muffle furnace, purge it under an argon atmosphere with a gas flow rate of 0.1 L / min, and maintain a heating rate of 15 °C / min. Heat it to 500 °C and calcine for 1 hour. After cooling to room temperature, wash it with a 10% hydrochloric acid solution and dry it in a 100 °C constant temperature drying oven for 2 hours to obtain pretreated humic acid.

[0072] ② Disperse the pretreated humic acid obtained in step ① in 100L of N,N-methylenebisacrylamide, add 4kg of polyacrylamide, stir and mix evenly, add 0.1kg of N,N'-dimethylethylenediamine and 0.4kg of glutaraldehyde, heat to 80℃, react for 3h, cool to room temperature, wash with 90% ethanol solution and dry to obtain modified humic acid.

[0073] The preparation method of activated biochar specifically includes the following steps:

[0074] A. Wash, dry, and pulverize 10 kg of biomass, pass it through a 100-mesh sieve, add 0.1 kg of pore-forming activator, mix well, place it in a muffle furnace, purge it under an argon atmosphere with a gas flow rate of 0.1 L / min, and maintain a heating rate of 10℃ / min until the temperature reaches 400℃. Calcinate for 1 h, cool to room temperature, soak in a 30% acetic acid solution for 4 h, wash with deionized water until the pH is 6.0, and dry in an 80℃ constant temperature drying oven for 1 h to obtain pretreated biochar.

[0075] B. The pretreated biochar was soaked in a mixed solution of Fe2(SO4)3 and Fe(NO3)2, ultrasonically treated for 30 min at 100 W and 40 °C, centrifuged at 8000 r / min for 1 h, the solid was collected, washed with deionized water until pH 6.8, and dried in a vacuum drying oven at 50 Pa and 80 °C for 2 h to obtain activated biochar.

[0076] Example 2

[0077] A method for producing organic fertilizer from livestock and poultry manure specifically includes the following steps:

[0078] S1. Remove impurities from 100 kg of poultry and livestock manure substrate, crush it, and pass it through a 20-mesh sieve. While turning the poultry and livestock manure substrate, spray it with a 2.5% calcium chloride aqueous solution. Let it stand for 3 hours, then rinse it with tap water. Dry it at 55℃ until the moisture content is 53%. Add 0.15 kg of γ-polyglutamic acid, inoculate it with activated compound probiotics, adjust the pH to 6.0, and place it in a sealed fermentation tank for fermentation at 32℃ for 4 days. Obtain the fermentation product, filter it through an 80-mesh sieve, and obtain the poultry and livestock manure-based fermentation liquid.

[0079] S2. Mix 100kg of poultry and livestock manure-based fermentation liquid, 4kg of microbial capsules, 15kg of modified humic acid, 12.5kg of activated biochar, 25kg of urea, 15kg of diammonium phosphate, and 6kg of manganese sulfate. Stir well, add water to adjust the moisture content to 55% of the total material, control the temperature at 55℃, and compost for 30 days. During this period, turn the pile every five days, cool it down to 35℃, and dry it to obtain the mixed fermented material.

[0080] S3. Granulate the mixed fermented material to obtain pretreated poultry and livestock manure organic fertilizer;

[0081] S4. Place the pretreated poultry and livestock manure organic fertilizer in a steam curing box with a temperature of 90℃ and a relative humidity of 65%, and heat it to 105℃ at a rate of 20℃ / h, and steam curing for 10h to obtain poultry and livestock manure organic fertilizer.

[0082] The preparation method of activated compound probiotics specifically includes the following steps: Trichoderma harzianum and Bacillus belye are inoculated into Gao's medium for activation culture at an activation temperature of 30°C for 2.5 days, and then mixed to obtain activated compound probiotics;

[0083] The preparation method of microbial capsules specifically includes the following steps:

[0084] (1) Dissolve 1.5 kg of carboxymethyl chitosan in 100 L of 2% acetic acid solution to obtain carboxymethyl chitosan solution; dissolve 4.5 kg of polyethylene glycol in 100 L of distilled water and heat to 88 °C to completely dissolve it to obtain polyethylene glycol aqueous solution; mix the carboxymethyl chitosan solution and polyethylene glycol aqueous solution, add 0.15 kg of sodium β-glycerophosphate, heat to 70 °C, stir at 450 rpm for 1.3 h, cool to room temperature to obtain shell material solution;

[0085] (2) Mix 1 kg of Trichoderma harzianum powder and 1 kg of Bacillus vesiculosus powder, add 5 kg of porous zeolite, disperse in linoleic acid, filter and dry to obtain core material;

[0086] (3) Add the core material to the shell material solution, stir evenly, add 0.015 kg of glutaraldehyde, emulsify at 9000 rpm for 8 min, homogenize 3 times at 40 MPa, freeze dry to obtain microbial capsules.

[0087] The preparation method of modified humic acid specifically includes the following steps:

[0088] ① Place 15 kg of humic acid in a muffle furnace, purge it with an argon atmosphere at a gas flow rate of 0.15 L / min, and maintain a heating rate of 18 °C / min. Heat the mixture to 650 °C and calcine for 1.5 h. After cooling to room temperature, wash it with a 12.5% ​​hydrochloric acid solution and dry it in a 100 °C constant temperature drying oven for 2.5 h to obtain pretreated humic acid.

[0089] ② Disperse the pretreated humic acid obtained in step ① in 100L N,N-methylenebisacrylamide, add 8kg polyacrylamide, stir and mix evenly, add 0.15kg triethylamine and 0.7kg polyvinyl alcohol, heat to 90℃, react for 4h, cool to room temperature, wash with 92% ethanol solution and dry to obtain modified humic acid.

[0090] The preparation method of activated biochar specifically includes the following steps:

[0091] A. Wash, dry, and pulverize 12.5 kg of biomass, pass it through a 100-mesh sieve, add 0.2 kg of pore-forming activator, mix evenly, place it in a muffle furnace, purge it under an argon atmosphere with a gas flow rate of 0.15 L / min, and maintain a heating rate of 15℃ / min until the temperature reaches 550℃. Calcinate for 1.5 h, cool to room temperature, soak in a 32.5% acetic acid solution for 5 h, wash with deionized water until the pH is 6.5, and dry in an 80℃ constant temperature drying oven for 1.5 h to obtain pretreated biochar.

[0092] B. The pretreated biochar was soaked in a mixed solution of Fe(NO3)3 and FeCl2, ultrasonically treated for 35 min at 200 W and 45 °C, centrifuged at 9000 r / min for 1.5 h, the solid was collected, washed with deionized water until pH 7.0, and dried in a vacuum drying oven at 85 °C and 60 Pa for 2.5 h to obtain activated biochar.

[0093] Example 3

[0094] A method for producing organic fertilizer from livestock and poultry manure specifically includes the following steps:

[0095] S1. Remove impurities from 100 kg of poultry and livestock manure substrate, crush it, pass it through a 20-mesh sieve, spray it with a 3% calcium chloride aqueous solution while turning the poultry and livestock manure substrate, let it stand for 3 hours, then rinse it with tap water, dry it at 60℃ until the moisture content is 55%, add 0.2 kg of γ-polyglutamic acid, inoculate it with activated compound probiotics, adjust the pH to 7.0, place it in a sealed fermentation tank for fermentation, fermentation temperature is 34℃, fermentation time is 5 days, obtain the fermentation product, filter it through an 80-mesh sieve, and obtain poultry and livestock manure-based fermentation liquid;

[0096] S2. Mix 100kg of poultry and livestock manure-based fermentation liquid, 5kg of microbial capsules, 20kg of modified humic acid, 10kg of activated biochar, 30kg of urea, 20kg of diammonium phosphate, and 7kg of manganese sulfate. Stir well, add water to adjust the moisture content to 60% of the total material, control the temperature at 60℃, and carry out composting fermentation for 30 days. During this period, turn the pile every five days, cool it down to 40℃, and dry it to obtain mixed fermented material.

[0097] S3. Granulate the mixed fermented material to obtain pretreated poultry and livestock manure organic fertilizer;

[0098] S4. Place the pretreated poultry and livestock manure organic fertilizer in a steam curing box with a temperature of 100℃ and a relative humidity of 70%, and heat it to 110℃ at a rate of 25℃ / h, and steam curing for 12 hours to obtain poultry and livestock manure organic fertilizer.

[0099] The preparation method of activated compound probiotics specifically includes the following steps: Trichoderma harzianum and Bacillus belye are inoculated into Gao's medium for activation culture at an activation temperature of 32℃ for 3 days, and then mixed to obtain activated compound probiotics;

[0100] The preparation method of microbial capsules specifically includes the following steps:

[0101] (1) Dissolve 2 kg of carboxymethyl chitosan in 100 L of 2% acetic acid solution to obtain carboxymethyl chitosan solution; dissolve 6 kg of polyethylene glycol in 100 L of distilled water and heat to 88 °C to completely dissolve it to obtain polyethylene glycol aqueous solution; mix carboxymethyl chitosan solution and polyethylene glycol aqueous solution, add 0.2 kg of sodium β-glycerophosphate, heat to 80 °C, stir at 500 rpm for 1.5 h, cool to room temperature to obtain shell material solution;

[0102] (2) Mix 1 kg of Trichoderma harzianum powder and 1 kg of Bacillus vesiculosus powder, add 6 kg of porous zeolite, disperse in linoleic acid, filter and dry to obtain core material;

[0103] (3) Add the core material to the shell material solution, stir evenly, add 0.02 kg of glutaraldehyde, emulsify at 10000 rpm for 10 min, homogenize 3 times at 50 MPa, freeze dry to obtain microbial capsules.

[0104] The preparation method of modified humic acid specifically includes the following steps:

[0105] ① Place 20 kg of humic acid in a muffle furnace, purge it with an argon atmosphere at a gas flow rate of 0.2 L / min, and maintain a heating rate of 20 °C / min. Heat it to 800 °C and calcine for 2 hours. After cooling to room temperature, wash it with a 15% hydrochloric acid solution and dry it in a 100 °C constant temperature drying oven for 3 hours to obtain pretreated humic acid.

[0106] ② Disperse the pretreated humic acid obtained in step ① in 100L N,N-methylenebisacrylamide, add 12kg polyacrylamide, stir and mix evenly, add 0.2kg hexamethylenediamine and 1kg glycerol, heat to 100℃, react for 5h, cool to room temperature, wash with 95% ethanol solution and dry to obtain modified humic acid.

[0107] The preparation method of activated biochar specifically includes the following steps:

[0108] A. Wash, dry, and pulverize 15 kg of biomass, pass it through a 100-mesh sieve, add 0.3 kg of pore-forming activator, mix well, place it in a muffle furnace, purge it under an argon atmosphere with a gas flow rate of 0.2 L / min, and maintain a heating rate of 20℃ / min until the temperature reaches 700℃. Calcinate for 2 hours, cool to room temperature, soak in a 35% acetic acid solution for 6 hours, wash with deionized water until the pH is 7.0, and dry in an 80℃ constant temperature drying oven for 2 hours to obtain pretreated biochar.

[0109] B. The pretreated biochar was soaked in a mixed solution of Fe(NO3)3 and FeCl2, ultrasonically treated for 40 min at 300 W and 50 °C, centrifuged at 10000 r / min for 2 h, the solid was collected, washed with deionized water until pH 7.2, and dried in a vacuum drying oven at 70 Pa and 90 °C for 3 h to obtain activated biochar.

[0110] Comparative Example 1

[0111] This comparative example provides a method for producing organic fertilizer from livestock and poultry manure. The only difference between this method and Example 1 is that the microorganisms are not encapsulated, i.e., the solution is without a shell. The other components, component contents, and preparation methods are the same as in Example 1.

[0112] Comparative Example 2

[0113] This comparative example provides a method for preparing organic fertilizer using livestock and poultry manure. The only difference between this method and Example 1 is that the carboxymethyl chitosan solution used for the microcapsule shell is not modified with polyethylene glycol and sodium β-glycerophosphate. The other components, component contents, and preparation methods are the same as in Example 1.

[0114] Comparative Example 3

[0115] This comparative example provides a method for producing organic fertilizer from livestock and poultry manure. The only difference between this method and Example 1 is that the humic acid is not modified. The other components, component contents, and preparation methods are the same as in Example 1.

[0116] Comparative Example 4

[0117] This comparative example provides a method for preparing organic fertilizer using livestock and poultry manure. The only difference between this method and Example 1 is that biochar is not added to the organic fertilizer. The other components, component contents, and preparation methods are the same as in Example 1.

[0118] Experimental Example 1

[0119] In this experimental example, the microbial capsules described in Example 1 were scanned using an electron microscope. Figure 1 This is a 500x magnified electron microscope scan of the surface of the microbial capsules prepared in Example 1 of the present invention.

[0120] Experimental Example 2

[0121] 1g of the organic fertilizer samples prepared in Example 1 and Comparative Examples 1-4 were placed in test tubes. 1000mL of deionized water was added to the test tubes to adjust the pH to 5.0, 7.0 and 9.0 respectively. The samples were stored for 7 days. After 7 days, the content of organic fertilizer in the deionized water was measured to analyze the stability of organic fertilizer to environmental pH.

[0122] Figure 2 The figures show the stability results of the organic fertilizers prepared in Examples 1 and Comparative Examples 1-4 after 7 days of storage in different pH environments. As shown in the figures, the organic fertilizer in Example 1 maintained a survival rate of over 80.1% in acidic, neutral, and alkaline environments. The organic fertilizer in Comparative Example 1 had the lowest survival rate, reaching only about 42.5% in various environments. The survival rates of the organic fertilizers in Comparative Examples 2 and 3 were 68.3-72.3%, and the survival rate of the organic fertilizer in Comparative Example 4 was about 57.4%. This indicates that the use of modified carboxymethyl chitosan as the shell material to coat the microbial powder, grafting polyacrylamide to modify humic acid to give it a tighter cross-linked structure, and soaking the biochar in acetic acid to remove surface impurities and increase the pore structure, allowing it to dissolve in a mixture of ferric and divalent salts to generate magnetic biochar, all contribute to the synergistic effect of the components, improving the acid and alkali resistance of the organic fertilizer, thus enabling the organic fertilizers in the examples to maintain a high survival rate in acidic, neutral, and alkaline environments.

[0123] Experimental Example 3

[0124] 1g of the organic fertilizer samples prepared in Example 1 and Comparative Examples 1-4 were placed in test tubes, and 100mL of deionized water was added to the test tubes. The test tubes were placed in environments of -15℃, 25℃, and 50℃ for 7d, 30d, and 180d, respectively, to test their stability at different temperatures and times. The presence of material precipitation, damage to the organic fertilizer spheroids, and precipitation was observed. The quality of the organic fertilizer was determined by the amount of material precipitation, the degree of damage to the organic fertilizer spheroids, and the amount of precipitation. The effects of temperature and time on the stability of the organic fertilizer were investigated. The test results are shown in Table 1.

[0125] Table 1. Effects of temperature and time on the stability of organic fertilizer

[0126]

[0127] As shown in Table 1, compared with the organic fertilizers prepared in Comparative Examples 1-4, the organic fertilizer prepared in Example 1 of the present invention does not exhibit material precipitation, organic fertilizer spherical morphology damage, or sedimentation when stored in low temperature, room temperature, and high temperature environments for one week, one month, and six months, demonstrating good stability.

[0128] Experiment Example 4

[0129] The fermentation time of organic fertilizer produced by the production methods of Examples 1-3 and Comparative Examples 1-4 was statistically analyzed, and the effects of the organic fertilizers produced by Examples 1-3 and Comparative Examples 1-4 on the physical and chemical properties of the soil were determined. Experimental treatment: A test site in Rizhao City, Shandong Province was selected and divided into 8 small plots of equal area, with a spacing of 0.5m between each small plot. The organic fertilizers described in Examples 1-3 and Comparative Examples 1-4 were applied to the test soil at a rate of 40 kg / mu. Water was used as a blank control group. The various physical and chemical properties of the soil were measured after 45 days.

[0130] Performance testing: Atomic absorption spectrometry was used to determine the content of lead, mercury, and copper heavy metal pollutants in the soil; potassium dichromate titration method was used to determine the organic matter content; semi-micro Kjeldahl method was used to determine the total nitrogen content; photoelectric colorimetry was used to determine the available phosphorus content; flame photometry was used to determine the available potassium content; indophenol colorimetry was used to determine urease; disodium phenyl phosphate colorimetry was used to determine phosphatase; phenol oxidation method was used to determine catalase; and conductivity method was used to determine the total salt content. The test results are shown in Table 2.

[0131] Table 2 Results of Soil Physicochemical Properties Measurement

[0132]

[0133] As shown in Table 2, the organic fertilizers prepared in Examples 1-3 of this invention require a short fermentation time and can effectively reduce the content of heavy metal pollutants in the soil, with a heavy metal pollutant removal rate of 62.1%. They also increase the content of soil organic matter, total nitrogen, available phosphorus and potassium, urease, phosphatase, and catalase, which is beneficial to improving crop growth and increasing crop yield in the soil. Furthermore, they reduce the total salt content of the soil; the organic fertilizers in Examples 1-3 reduced the total salt content by an average of 43.2%, which is beneficial to the remediation of saline-alkali soil. This indicates that the organic fertilizers prepared in Examples 1-3 of this invention help improve the soil environment.

[0134] Experimental Example 5

[0135] Weigh 1.0g of the uniformly sized organic fertilizer prepared in Examples 1-3 and Comparative Examples 1-4 respectively, place it in a 3cm×3cm 60-mesh gauze bag, seal it, and label it. Then weigh 100g of air-dried soil (moisture content less than 3.0%) into a self-sealing plastic bag, evenly sprinkle 20mL of distilled water to moisten the soil, seal the bag, and place it in a constant temperature incubator at 25℃ for 24 hours. Then bury the gauze bag containing the organic fertilizer in soil with a pH of 7 to begin cultivation for 40 days. Samples were taken at 3d, 5d, 8d, 12d, 16d, 20d, 26d, 32d, and 40d, dried, and analyzed for nutrient content using a soil nutrient analyzer. The cumulative nitrogen fertilizer release rate during the cultivation period was calculated using the following formula:

[0136]

[0137] Among them, v—cumulative nitrogen fertilizer release rate (%), w t —The mass fraction of nitrogen fertilizer release measured within time t; w—The mass fraction of total nutrients in the pesticide-fertilizer composition.

[0138] Figure 3The figures show the cumulative nitrogen release results of the organic fertilizer granules prepared in Examples 1-3 and Comparative Examples 1-4 of this invention. As shown, the organic fertilizer granules in Examples 1-3 reached nutrient release saturation in approximately 32 days, at which point the cumulative nitrogen release rate reached 72.3-73.8%; the organic fertilizer granules in Comparative Example 1 reached nutrient release saturation in approximately 5 days, at which point the cumulative nitrogen release rate was as high as 91.2%; the organic fertilizer granules in Comparative Example 2 reached nutrient release saturation in approximately 12 days, at which point the cumulative nitrogen release rate was only 64.0%; the organic fertilizer granules in Comparative Example 3 reached nutrient release saturation in approximately 16 days, at which point the cumulative nitrogen release rate was only 52.6%; and the organic fertilizer granules in Comparative Example 4 reached nutrient release saturation in approximately 8 days, at which point the cumulative nitrogen release rate was as high as 83.6%. The organic fertilizers in Examples 1-3 contain microorganisms encapsulated in modified carboxymethyl chitosan microcapsules. The modified humic acid and activated biochar work synergistically to provide a growth and reproduction site and nutrients for the microorganisms. This method effectively mitigates the release of microorganisms, thus achieving the technical effect of slow and controlled fertilizer release. A lag period for nitrogen fertilizer release occurs, with fertilizer nutrients remaining for eight days before slow release begins. In Comparative Example 1, microorganisms are directly added to the poultry and livestock manure substrate for fermentation, resulting in faster microbial release and rapid nutrient release saturation. In Comparative Example 2, the microorganisms in the organic fertilizer are coated with unmodified carboxymethyl chitosan. The poor stability of single carboxymethyl chitosan makes the microcapsule structure easily decompose in the soil environment, causing fertilizer nutrients to be released after 12 days. In Comparative Example 3, the unmodified humic acid prevents the formation of tight cross-linked structures between the organic fertilizer components, making nutrient release easier compared to Examples 1-3. In Comparative Example 4, no biochar is added. The single poultry and livestock manure substrate composting process easily leads to compost pile collapse and material adhesion, resulting in incomplete fermentation, affecting the utilization rate and fertilizer efficiency of the organic fertilizer, and causing rapid nutrient release.

[0139] Experimental Example 6

[0140] Experimental treatments: The experiment adopted a randomized block design with 7 treatments, using the organic fertilizers prepared in Examples 1-3 and Comparative Examples 1-4, respectively, with water as a blank control group. The experiment was repeated 3 times, for a total of 24 plots, with a protective row between each plot. Ten Chinese cabbage seeds were evenly spread on the soil surface and covered with 2 cm of soil. The soil moisture was maintained at 50% by watering regularly. After 30 days of growth, the grown Chinese cabbages were removed from the soil, washed with water, and the root length, plant height, dry weight, and wet weight of the Chinese cabbages were measured. The contents of vitamin C, chlorophyll a, total carbon, total nitrogen, total phosphorus, and total potassium were also determined.

[0141] Table 3 Results of the growth performance test of Chinese cabbage

[0142]

[0143] As shown in Table 3, compared with the blank control group, the organic fertilizer described in Examples 1-3 of this invention is beneficial to improving the growth performance of crops. The root length, plant height, dry weight and wet weight of Examples 1-3 increased by an average of 49.5%. Compared with Comparative Examples 1-4, it can be seen that adding microorganisms, modified humic acid and activated biochar encapsulated in poultry and livestock manure substrate is beneficial to improving various growth performance indicators of crops.

[0144] Table 4 Results of Nutritional Quality Measurement of Chinese Cabbage

[0145]

[0146] As shown in Table 4, compared with the blank control group, the organic fertilizer described in Examples 1-3 of this invention is beneficial to improving the nutritional quality of crops. The total carbon content of Examples 1-3 increased by an average of 43.2%, the total nitrogen content increased by an average of 46.4%, the total phosphorus content increased by an average of 62.3%, and the total potassium content increased by an average of 46.5%. Compared with Comparative Examples 1-4, Examples 1-3 show that adding encapsulated microorganisms, modified humic acid, and activated biochar to poultry and livestock manure substrate is beneficial to improving the various nutritional qualities of crops.

[0147] Figure 4 The figure shows the effect of the organic fertilizers prepared in Example 1 and Comparative Examples 1-4 on the nutritional quality of Chinese cabbage. As shown in the figure, the vitamin C content of Example 1 and Comparative Example 3 was significantly higher than that of the blank control group (P<0.05), increasing by 32.88% and 26.58% respectively. The vitamin C content of Comparative Examples 1, 2, and 4 was not significantly different from that of the blank control group (P>0.05), but showed an upward trend. The nitrate content of Example 1 was significantly higher than that of the blank control group (P<0.05), increasing by 35.18%. The nitrate content of Comparative Examples 1-4 was not significantly different from that of the blank control group (P>0.05). The microorganisms in the organic fertilizer prepared in Comparative Example 1 were not encapsulated, resulting in a significant decrease in stability. The microbial capsule shell solution in the organic fertilizer prepared in Comparative Example 2 only contained a single carboxymethyl chitosan, leading to decreased membrane stability. The humic acid in the organic fertilizer prepared in Comparative Example 3 was not modified, affecting the soil environment and failing to synergistically improve the stability of the organic fertilizer with activated biochar. The organic fertilizer prepared in Comparative Example 4 did not contain biochar, and the fermentation of the single poultry and livestock manure substrate was incomplete, affecting the fermentation quality. As a result, the fertilizer efficiency of the organic fertilizers in Comparative Examples 1-4 all decreased.

[0148] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

[0149] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention. The actual application is not limited to this. In conclusion, if those skilled in the art are inspired by this description and design similar methods and embodiments without departing from the spirit of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A method for producing organic fertilizer from livestock and poultry manure, characterized in that: Includes the following steps: S1. Remove impurities from the poultry and livestock manure substrate, crush it, and pass it through a 20-mesh sieve. While turning the poultry and livestock manure substrate, spray it with calcium chloride aqueous solution, let it stand for 3 hours, then rinse it with tap water, and dry it at 50-60℃ until the moisture content is 50-55%. Add γ-polyglutamic acid, inoculate it with activated compound probiotics, adjust the pH to 5.0-7.0, and place it in a sealed fermentation tank for fermentation. The fermentation temperature is 30-34℃, and the fermentation time is 3-5 days. The fermentation product is obtained and filtered through an 80-mesh sieve to obtain poultry and livestock manure-based fermentation liquid. S2. Mix the poultry and livestock manure-based fermentation liquid, microbial capsules, modified humic acid, activated biochar, urea, diammonium phosphate, and trace elements, stir evenly, add water to adjust the moisture content to 50-60% of the total material, control the temperature at 50-60℃, and carry out composting fermentation for 30 days. During this period, turn the pile every five days, cool it down to 30-40℃, and dry it to obtain the mixed fermented material. S3. Granulate the mixed fermented material to a particle size of 1.5-4.5mm to obtain pretreated poultry and livestock manure organic fertilizer; S4. Steam curing the pretreated poultry and livestock manure organic fertilizer to obtain poultry and livestock manure organic fertilizer; The preparation method of the microbial capsules specifically includes the following steps: (1) Dissolve carboxymethyl chitosan in a 2% acetic acid solution to obtain a 1-2% carboxymethyl chitosan solution; dissolve polyethylene glycol in distilled water and heat to 80-95℃ to completely dissolve it to obtain a 3-6% polyethylene glycol aqueous solution; mix the carboxymethyl chitosan solution and the polyethylene glycol aqueous solution, add sodium β-glycerophosphate, heat to 60-80℃, stir at a rate of 400-500 rpm for 1-1.5 h, cool to room temperature to obtain a shell material solution; (2) Mix Trichoderma harzianum powder and Bacillus vesiculosus powder, add porous zeolite, disperse in linoleic acid, filter and dry to obtain core material; (3) Add the core material to the shell material solution, stir evenly, add glutaraldehyde, emulsify at high speed, freeze dry to obtain microbial capsules; In step (1), the weight ratio of carboxymethyl chitosan, polyethylene glycol, and sodium β-glycerophosphate is 1-2:3-6:0.1-0.2; In step (2), the weight ratio of Trichoderma harzianum powder, Bacillus belyi powder, and porous zeolite is 1:1:4-6; In step (3), the weight ratio of carboxymethyl chitosan to glutaraldehyde is 1:0.01-0.02; The high-speed emulsification is carried out at a speed of 8000-12000 rpm for 5-10 minutes, followed by homogenization at 30-50 MPa three times. The preparation method of the modified humic acid specifically includes the following steps: ① Place humic acid in a muffle furnace, purge it under an argon atmosphere with a gas flow rate of 0.1-0.2 L / min, and maintain a heating rate of 15-20℃ / min. Heat it to 500-800℃ and calcine for 1-2 hours. After cooling to room temperature, wash it with a 10-15% hydrochloric acid solution and dry it in a 100℃ constant temperature drying oven for 2-3 hours to obtain pretreated humic acid. ② Disperse the pretreated humic acid obtained in step ① in N,N-methylenebisacrylamide, add polyacrylamide, stir and mix evenly, add initiator and crosslinking agent, heat to 80-100℃, react for 3-5h, cool to room temperature, wash with 90-95% ethanol solution and dry to obtain modified humic acid. In step ②, the weight ratio of humic acid, polyacrylamide, initiator, and crosslinking agent is 10-20:4-12:0.1-0.2:0.4-1; The initiator includes at least one of N,N'-dimethylethylenediamine, triethylamine, and hexamethylenediamine; The crosslinking agent includes at least one of glutaraldehyde, polyvinyl alcohol, and glycerol.

2. The method for preparing organic fertilizer using livestock and poultry manure according to claim 1, characterized in that: In step S1, the poultry and livestock manure substrate includes at least one of cow manure, sheep manure, pig manure, and chicken manure; The mass fraction of the calcium chloride aqueous solution is 2-3%; The weight ratio of the poultry and livestock manure substrate to γ-polyglutamic acid is 100:0.1-0.2; The preparation method of the activated compound probiotics specifically includes the following steps: Trichoderma harzianum and Bacillus belye are inoculated into Gao's medium for activation culture at an activation temperature of 28-32℃ for 2-3 days, and then mixed to obtain activated compound probiotics; The viable count of the *Trichoderma harzianum* was 1.5 × 10⁻⁶. 8 CFU / g or higher; the viable count of the *Bacillus belyssae* is 2.3 × 10⁻⁶. 7 CFU / g or higher; The amount of activated compound probiotics added is 3-5% of the weight of poultry and livestock manure substrate.

3. The method for preparing organic fertilizer using livestock and poultry manure according to claim 1, characterized in that: In step S2, the trace elements include at least one of ferrous sulfate, manganese sulfate, zinc sulfate, manganese sulfate, copper sulfate pentahydrate, and borax. The weight ratio of the poultry and livestock manure-based fermentation liquid, microbial capsules, modified humic acid, activated biochar, urea, diammonium phosphate, and trace elements is 100:3-5:10-20:10-15:20-30:10-20:5-7.

4. The method for preparing organic fertilizer using livestock and poultry manure according to claim 1, characterized in that: In step S4, the steam curing involves placing the material in a steam curing chamber with a temperature of 80-100℃ and a relative humidity of 60-70%, raising the temperature to 100-110℃ at a rate of 15-25℃ / h, and steam curing for 8-12 hours.

5. The method for preparing organic fertilizer using livestock and poultry manure according to claim 1, characterized in that: The method for preparing the activated biochar specifically includes the following steps: A. Wash, dry, and pulverize the biomass, pass it through a 100-mesh sieve, add a pore-forming activator, mix evenly, place it in a muffle furnace, purge it under an argon atmosphere with a gas flow rate of 0.1-0.2 L / min, and maintain a heating rate of 10-20℃ / min, heat it to a temperature of 400-700℃, calcine for 1-2 hours, cool it to room temperature, soak it in a 30-35% acetic acid solution for 4-6 hours, wash it with deionized water until the pH is 6.0-7.0, and dry it in an 80℃ constant temperature drying oven for 1-2 hours to obtain pretreated biochar; B. Immerse the pretreated biochar in Fe 3+ and Fe 2+ In the mixed solution, ultrasonic treatment was carried out for 30-40 minutes at a power of 100-300W and a temperature of 40-50℃. The mixture was then centrifuged at a speed of 8000-10000r / min for 1-2 hours. The solid was collected, washed with deionized water until the pH reached 6.8-7.2, and dried in a vacuum drying oven at a vacuum degree of 50-70Pa and a temperature of 80-90℃ for 2-3 hours to obtain activated biochar.

6. The method for preparing organic fertilizer using livestock and poultry manure according to claim 5, characterized in that: In step A, the biomass is one or a mixture of several of the following: rice bran, wheat bran, soybean meal, and straw. The pore-forming activator includes at least one of potassium carbonate, potassium hydroxide, and calcium phosphate. The weight ratio of the biomass to the pore-forming activator is 10:0.1-0.3; In step B, the Fe 3+ Including any one of Fe2(SO4)3, Fe(NO3)3, and FeCl3; The Fe 2+ It includes any one of FeSO4, Fe(NO3)2, and FeCl2.

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