Preparation method of straw livestock and poultry manure synergistic mature organic fertilizer

Abstract

The present application relates to the technical field of organic fertilizer preparation, and discloses a preparation method of straw and livestock and poultry manure synergistic compost organic fertilizer, which comprises the following steps: carrying out pre-loading treatment on dry base straw by combining a high molecular interface dispersing agent with calcium peroxide; mixing the pretreated straw with livestock and poultry manure and the like, and carrying out low-moisture initial pile building by adopting a staged water control strategy; when the preset fermentation conditions are met, triggering mechanical turning and throwing and atomizing and spraying process water to carry out aerobic fermentation. In the present application, the high molecular interface dispersing agent carries the calcium peroxide to target into the internal pores of the straw, local hydrolysis occurs when water is triggered, the released active oxygen and chemical heat energy are used to break down the lignocellulose skeleton, in-situ oxygen release and heat compensation are realized, and the start-up and temperature rising period is shortened; at the same time, the adsorption of the substrate is combined, free ammonia gas in the high-temperature period is effectively captured, humic acid condensation is promoted, total nitrogen loss is reduced, and the fertilizer retention and nitrogen fixation efficiency of the organic fertilizer product is improved.

Description

Technical Field

[0001] This invention relates to the field of organic fertilizer preparation technology, specifically to a method for preparing organic fertilizer by co-composting straw and livestock manure. Background Technology

[0002] Aerobic composting of agricultural straw with livestock manure is a mainstream approach to the resource utilization of agricultural organic solid waste. Straw is rich in carbon, while livestock manure is rich in nitrogen; synergistic composting can effectively regulate the carbon-nitrogen ratio and improve the material structure. However, in actual industrial production, this synergistic fermentation process still has limitations. Traditional processes typically adjust the moisture content of the mixture to a high level at the initial stage of composting to meet the water consumption during long-term fermentation. This moisture management method leads to a decrease in the porosity of the compost pile, resulting in poor internal aeration and the creation of localized anaerobic environments. This causes slow temperature rise in the early stages of fermentation and makes the pile prone to suffocation.

[0003] To accelerate material decomposition, conventional methods often involve adding various auxiliary agents, but this is usually done in a crude manner, mixing all agents with the main and auxiliary materials at once. This mixing method makes it easy for various reagents to undergo cross-antagonistic reactions in the complex system, reducing conditioning efficiency. In particular, the lignocellulose structure of straw is very dense, making it difficult for agents dispersed throughout the compost pile to adhere to the straw surface for effective decomposition, resulting in straw decomposition lagging significantly behind manure. Furthermore, when the external ambient temperature is low or the initial microbial activity is insufficient, traditional composting systems lack effective auxiliary oxygen supply and heat compensation mechanisms. Once the initial stage of composting is hindered, conventional mechanical turning alone is insufficient to quickly reverse the deep-seated anoxic and low-temperature conditions, ultimately leading to a prolonged fermentation cycle and unstable quality of the finished organic fertilizer. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a method for preparing organic fertilizer by co-composting straw and livestock manure, which solves the problems of slow straw degradation, low fermentation efficiency, and easy nutrient volatilization and loss that exist in traditional straw and livestock manure composting.

[0005] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a method for preparing organic fertilizer by co-composting straw and livestock manure, using the following technical solution: A method for preparing organic fertilizer by co-composting straw and livestock manure includes the following steps: Take dry straw and crush it. Add calcium peroxide powder and polymeric interfacial dispersant under stirring to form a preloaded material. Spray process water to adjust the moisture content of the preloaded material. After mixing, place it statically to obtain preloaded straw. Take livestock and poultry manure, add citric acid monohydrate, ferrous sulfate heptahydrate and superphosphate in sequence, stir and mix to obtain manure mixture, adjust the final pH value of manure mixture to obtain conditioned manure; Preloaded straw is mixed with conditioned manure to obtain a blend. The moisture content of the blend is adjusted, and the blend is piled up to obtain a pile. The pile is then allowed to start natural heating and fermentation. Monitor the temperature data of the pile. When the preset fermentation conditions are met, turn the pile over and spray process water into the pile at the same time to increase the moisture content of the pile. After increasing the moisture content of the compost pile, the pile is kept fermented and turned over to undergo a high-temperature fermentation period. After the high-temperature fermentation period ends, the compost pile is aged until it is fully decomposed and organic fertilizer is produced.

[0006] By adopting the above technical solutions, the use of straw dispersion oxidation pretreatment, manure nitrogen retention, acidity adjustment and quality conditioning, and staged moisture regulation fermentation process can achieve the effects of shortening the fermentation cycle, reducing nitrogen loss and improving fertilizer maturity.

[0007] The detailed explanation of the mechanism is as follows: Firstly, during the straw pretreatment stage, calcium peroxide powder and a polymeric interfacial dispersant are added, and the moisture content is adjusted. The polymeric interfacial dispersant has surface activity, which reduces the surface tension of water, promoting the penetration of process water and calcium peroxide into the internal pores of the straw. During the storage process, calcium peroxide reacts with water to continuously generate calcium hydroxide and slowly release oxygen. The synergistic effect of the locally slightly alkaline environment and reactive oxygen species disrupts the dense cross-linked structure of cellulose and lignin in the straw, causing the cellulose to swell and peel off, providing contact sites for subsequent aerobic microbial attachment and enzymatic hydrolysis.

[0008] Secondly, during the manure conditioning stage, ammonia is easily lost through volatilization during the composting process of livestock and poultry manure. Adding citric acid monohydrate can neutralize free ammonia in the manure, generating stable ammonium salts, thus achieving ammonia fixation and nitrogen retention. The ferrous ions provided by ferrous sulfate heptahydrate can combine with sulfides in the compost to form precipitates, reducing hydrogen sulfide emissions. Furthermore, ferric ions participate in the condensation reaction of humic substances during fermentation, promoting the formation of humic acid macromolecules. Superphosphate introduces a readily available phosphorus source, maintaining the free activity of phosphate ions in an acidic system and increasing the available phosphorus content of organic fertilizer.

[0009] Finally, in the co-fermentation stage, pre-loaded straw is mixed with conditioned manure and piled up. The calcium peroxide loaded onto the straw in the early stage continuously releases oxygen during the fermentation initiation period, improving the internal microenvironment of the pile and preventing the production of sour and foul-smelling substances due to localized anaerobic fermentation. When the pile temperature reaches the preset conditions, vigorous microbial metabolism leads to rapid moisture evaporation. Simultaneous turning and spraying of process water raises the moisture content, replenishing moisture in a timely manner, maintaining the metabolic activity of thermophilic microorganisms, and allowing the pile to remain at high temperature for sufficient time to kill pathogens, accelerate the complete degradation of materials, and ultimately stabilize the fertilizer effect through aging.

[0010] Preferably, the proportions of each raw material are as follows: 100 parts by weight of dry straw; 150-250 parts by weight of livestock and poultry manure; 1.0-2.0 parts by weight of calcium peroxide powder; 0.3-0.5 parts by weight of polymeric interfacial dispersant; Citric acid monohydrate, 0.5-1.0 parts by weight; Ferrous sulfate heptahydrate 1.0-2.0 parts by weight; 1.0-2.0 parts by weight of superphosphate.

[0011] By adopting the above technical solution, the above ratio controls the carbon-to-nitrogen ratio of the fermentation system within a suitable range for microbial growth. The matching dosage of calcium peroxide and dispersant can achieve moderate cell wall disruption of straw without causing severe alkalization of the system. The combined dosage of citric acid, ferrous sulfate, and superphosphate meets the requirements for neutralizing free ammonia in manure and precipitating sulfides, while ensuring a balanced nitrogen, phosphorus, and potassium content in the fermented organic fertilizer.

[0012] Preferably, the dry-based straw is one or a mixture of several of corn straw, wheat straw and rice straw; Livestock and poultry manure is a mixture of one or more of chicken manure, pig manure, and cow manure.

[0013] By adopting the above technical solution, common agricultural waste is used as a carbon and nitrogen source substrate to achieve the resource utilization of solid waste. The selected straw all have a typical lignocellulose structure, and the selected livestock and poultry manure is rich in organic matter and natural microbial communities, making it suitable for the aforementioned combined conditioning and fermentation process.

[0014] Preferably, when adjusting the moisture content of the preloaded material, the moisture content of the preloaded material is adjusted to between 20% and 25%. When adjusting the final pH value of the fecal mixture, adjust the final pH value of the fecal mixture to 6.5–7.3; When adjusting the moisture content of the blend, adjust the moisture content of the blend to between 45% and 50%; When increasing the moisture content of the pile, the moisture content of the pile is increased to between 55% and 60%.

[0015] By adopting the above technical solutions, the pre-loaded material is controlled within a low moisture content range, which avoids excessive moisture causing pore blockage in the straw and ensures a slow reaction of calcium peroxide. The manure mixture is adjusted to a weakly acidic to neutral pH range, effectively inhibiting urease activity and blocking the ammonia production pathway from urea decomposition. The initial moisture content of the compost pile is controlled at a moderate level to ensure adequate aeration during the fermentation initiation stage, promoting temperature rise. During the high-temperature period, the moisture content is raised to a higher level to offset moisture loss due to high-temperature evaporation and maintain the water activity required for microbial reproduction.

[0016] Preferably, the polymeric interfacial dispersant is modified sodium lignosulfonate, which has a weight-average molecular weight of 11,000–24,000 Da and a sulfonic acid group content of 1.6–2.4 mmol / g.

[0017] By adopting the above technical solution, modified sodium lignin sulfonate with a weight-average molecular weight in this range exhibits a moderate steric hindrance effect, while the sulfonic acid groups provide hydrophilic properties and electrostatic repulsion. This adjuvant adsorbs onto the surface of straw particles, improving the wettability of the straw surface, promoting the uniform distribution of moisture and calcium peroxide within the straw system, and preventing localized agglomeration and clumping of the agent.

[0018] Preferably, the modified sodium lignosulfonate is prepared by the following steps: Take 100 parts by weight of black liquor from paper mill softwood sulfite pulping, filter it through a microfiltration membrane with a pore size of 0.1-0.5 μm at room temperature, and collect the clear microfiltrate. Add dilute sulfuric acid solution to the microfiltrate to adjust the pH to 3.0-4.0 to obtain an acid-adjusted solution; Add 1.0-2.0 parts by weight of a 37% formaldehyde solution to the acid-adjusting solution, seal and heat to 85-95℃ for 2.0-3.0 hours to obtain the modified reaction solution; After the modified reaction solution is cooled, it is washed and concentrated using an ultrafiltration membrane with a molecular weight cutoff of 5000-10000 Da. The ultrafiltration retentate is collected and dried to obtain modified sodium lignosulfonate.

[0019] By employing the above technical solution, the extraction of sodium lignin sulfonate from papermaking black liquor can reduce the cost of auxiliary agents. Microfiltration removes large particulate impurities. Formaldehyde is added under acidic conditions for condensation modification, causing cross-linking of lignin molecules and increasing the weight-average molecular weight of the product. Ultrafiltration membranes remove low-molecular-weight impurities and unreacted reagents, separating high-purity modified sodium lignin sulfonate with a concentrated molecular weight distribution, ensuring its interfacial dispersion performance.

[0020] Preferably, when taking dry straw and crushing it, the dry straw is crushed and cut into segments of 3-5 cm. After the process water is injected to adjust the moisture content of the preloaded material, it is mixed continuously for 20-30 minutes before being placed statically. After adding citric acid monohydrate, ferrous sulfate heptahydrate, and superphosphate in sequence, stir continuously for 20–30 minutes.

[0021] By adopting the above technical solution, straw is pulverized to a certain length range, balancing the increase of surface area with the maintenance of pile porosity, preventing excessively fine straw from causing pile compaction and oxygen deficiency. The time setting for continuous mixing and stirring ensures sufficient contact and mass transfer between the agent and the material, improving the homogeneity of the reaction system.

[0022] Preferably, when the blend is piled up to obtain a pile, the height of the pile is controlled between 1.0 and 1.5 m; The preset fermentation conditions are: The temperature in the core region of the reactor naturally rose for the first time and reached 50-55°C. Alternatively, the composting time can reach 72 hours and the temperature in the core area of ​​the compost pile can be below 50°C.

[0023] By adopting the above technical solutions, a pile of appropriate height can prevent excessive pressure at the bottom from creating dead zones, while also helping to maintain high internal temperatures. Two intervention scenarios are set for the fermentation conditions: the first is for the normal heating state, where turning and water replenishment are implemented when the high-temperature threshold is reached; The second approach targets slow-start conditions by physically turning the microbial community over and replenishing moisture.

[0024] Preferably, the specific method for increasing the moisture content of the pile is as follows: Using a high-pressure water pump and atomizing nozzles mounted on the turning equipment, process water is atomized and sprayed into the pile during the turning operation.

[0025] By adopting the above technical solution, the high-pressure water pump and atomizing nozzle generate fine water mist. Combined with the dispersing effect of the turning equipment, the water mist can be evenly attached to the surface of the splashed material, avoiding local over-wetting, clumping, and leaching of nutrients caused by rough water addition.

[0026] Preferably, after the high-temperature fermentation period ends, the pile is aged until it is fully decomposed. When the temperature difference between the core area of ​​the pile and the ambient temperature drops to ≤5℃, the decomposition is considered complete.

[0027] By adopting the above technical solution, the metabolism of microorganisms weakens in the later stage of fermentation after the easily degradable organic matter is consumed, and the heat production decreases accordingly. Using the temperature difference between the core temperature and the ambient temperature as a physical characterization indicator, the end point of decomposition can be directly determined, preventing secondary fermentation of organic fertilizer after it is applied to the soil.

[0028] This invention provides a method for preparing organic fertilizer by co-composting straw and livestock manure. It has the following beneficial effects: 1. This invention preloads dry straw with calcium peroxide and a polymeric interfacial dispersant, and independently conditions livestock and poultry manure with various agents before mixing the two together to build a pile. This avoids the antagonistic reaction caused by mixing compound reagents at once, allowing the interfacial dispersant and calcium peroxide to act on the straw surface to destroy its recalcitrant structure. At the same time, the conditioner improves the initial physicochemical properties of the manure, thereby increasing the synergistic degradation rate of the pile during subsequent fermentation.

[0029] 2. This invention adjusts the moisture content of the materials in stages. In the early stage of composting, the blend is kept at a low moisture content. After the compost meets the preset fermentation conditions, the moisture content of the compost is increased by turning and turning. The low moisture content in the early stage ensures the ventilation pores inside the compost, which promotes the rapid reproduction of aerobic microorganisms and achieves natural start-up and heating. At the same time, water is added during the high temperature period to meet the metabolic needs of microorganisms that consume a lot of water. This invention overcomes the problems of anaerobic suffocation and difficulty in heating caused by excessively high initial moisture settings in traditional composting.

[0030] 3. This invention establishes an intervention mechanism for the composting start-up process by monitoring and determining the temperature or fermentation time of the compost pile and combining the characteristics of calcium peroxide preloaded inside the material. When the temperature of the compost pile rises normally or the environment causes a slow start-up that reaches the preset conditions, the external turning and spraying of process water will induce the calcium peroxide distributed on the straw to undergo a hydrolysis reaction. The oxygen and heat released thereby improve the micro-oxygen environment in the deep layers of the compost pile and use chemical exothermics to make up for the insufficient heat generation of biomass in the early stage, thus ensuring the stability of the fermentation and maturation process. Attached Figure Description

[0031] Figure 1 These are the X-ray diffraction peak patterns of test objects A, B, and C in Test Example 1 of this invention; Figure 2 These are the Fourier transform infrared spectral peak spectra of test objects A, B, and C in Test Example 1 of this invention; Figure 3 This is the differential scanning calorimetry peak spectrum of the microscopic test object in Test Example 2 of this invention; Figure 4 This is the gas chromatographic peak spectrum of the interstitial gas of the macroscopic test object in Test Example 2 of this invention; Figure 5 This is the peak diagram of the dynamic evolution of fermentation temperature in Test Example 3 of this invention; Figure 6 These are the thermogravimetric peak spectra of the finished products of each test object in Test Example 4 of this invention; Figure 7 This is a peak spectrum of ammonia volatilization rate of some test subjects in Test Example 5 of the present invention. Detailed Implementation

[0032] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Preparation Example 1: This preparation example provides a method for preparing a polymeric interfacial dispersant, comprising the following steps: Take 100 parts by weight of black liquor from paper mill softwood sulfite pulping, filter it through a microfiltration membrane with a pore size of 0.3 μm at room temperature, and collect the clear microfiltrate. Add dilute sulfuric acid solution to the microfiltrate to adjust the pH to 3.5, and you will get an acid-adjusted solution. Add 1.5 parts by weight of a 37% formaldehyde solution to the acid-adjusting solution, seal and heat to 90℃ for 2.5 hours to obtain the modified reaction solution; After the modified reaction solution is cooled, it is washed and concentrated using an ultrafiltration membrane with a molecular weight cutoff of 8000 Da. The ultrafiltration retentate is collected and dried to obtain modified sodium lignosulfonate as a polymeric interfacial dispersant. The modified sodium lignosulfonate has a weight-average molecular weight of 18500 Da and a sulfonic acid group content of 2.0 mmol / g.

[0034] Preparation Example 2: This preparation example provides a method for preparing a polymeric interfacial dispersant, comprising the following steps: Take 100 parts by weight of black liquor from paper mill softwood sulfite pulping, filter it through a microfiltration membrane with a pore size of 0.1 μm at room temperature, and collect the clear microfiltrate. Add dilute sulfuric acid solution to the microfiltrate to adjust the pH to 3.0, and you will get an acid-adjusted solution. Add 1.0 part by weight of formaldehyde solution with a mass concentration of 37% to the acid-adjusting solution, seal and heat to 85℃ for 2.0 h to obtain the modified reaction solution; After the modified reaction solution is cooled, it is washed and concentrated using an ultrafiltration membrane with a molecular weight cutoff of 5000 Da. The ultrafiltration retentate is collected and dried to obtain modified sodium lignosulfonate as a polymeric interfacial dispersant. The modified sodium lignosulfonate has a weight-average molecular weight of 11000 Da and a sulfonic acid group content of 1.6 mmol / g.

[0035] Preparation Example 3: This preparation example provides a method for preparing a polymeric interfacial dispersant, comprising the following steps: Take 100 parts by weight of black liquor from paper mill softwood sulfite pulping, filter it through a microfiltration membrane with a pore size of 0.5 μm at room temperature, and collect the clear microfiltrate. Add dilute sulfuric acid solution to the microfiltrate to adjust the pH to 4.0, and you will get an acid-adjusted solution. Add 2.0 parts by weight of a 37% formaldehyde solution to the acid-adjusting solution, seal and heat to 95℃ for 3.0 h to obtain the modified reaction solution; After the modified reaction solution is cooled, it is washed and concentrated using an ultrafiltration membrane with a molecular weight cutoff of 10000 Da. The ultrafiltration retentate is collected and dried to obtain modified sodium lignosulfonate as a polymeric interfacial dispersant. The modified sodium lignosulfonate has a weight-average molecular weight of 24000 Da and a sulfonic acid group content of 2.4 mmol / g.

[0036] Example 1: This embodiment provides a method for preparing organic fertilizer by co-composting straw and livestock manure, including the following steps: Take 100 parts by weight of dry base straw, i.e. naturally air-dried corn straw, and crush and cut it into 4cm segments. Add 1.5 parts by weight of calcium peroxide powder and 0.4 parts by weight of the polymer interface dispersant obtained in Preparation Example 1 under stirring to form a preloaded material. Spray process water to adjust the moisture content of the preloaded material to 22%. After continuous mixing for 25 minutes, let it stand statically to obtain preloaded straw. Take 200 parts by weight of livestock and poultry manure, i.e., fresh chicken manure, and add 0.75 parts by weight of citric acid monohydrate, 1.5 parts by weight of ferrous sulfate heptahydrate and 1.5 parts by weight of superphosphate in sequence. Stir continuously for 25 minutes to obtain a manure mixture. Adjust the final pH value of the manure mixture to 7.0 to obtain conditioned manure. Preloaded straw and conditioned manure are mixed to obtain a blend. The moisture content of the blend is adjusted to 48%. The blend is piled up to obtain a pile. The height of the pile is controlled at 1.2m. The pile is then allowed to start natural heating and fermentation. The temperature data of the pile is monitored. When the preset fermentation conditions are met, that is, when the temperature in the core area of ​​the pile rises naturally for the first time and reaches 52°C, the pile is turned over using a high-pressure water pump and atomizing nozzles mounted on the turning equipment. At the same time, process water is sprayed into the pile to increase the moisture content of the pile to 58%. After increasing the moisture content of the compost pile, the pile is kept fermented and turned over to undergo a high-temperature fermentation period. After the high-temperature fermentation period lasts for 18 days, the compost pile is aged until it is fully decomposed. When the temperature in the core area of ​​the compost pile drops to ≤5℃ from the ambient temperature, it is considered to be fully decomposed and organic fertilizer is obtained.

[0037] Example 2: This embodiment provides a method for preparing organic fertilizer by co-composting straw and livestock manure, including the following steps: Take 100 parts by weight of dry base straw, i.e. naturally air-dried wheat straw, and crush and cut it into 3cm segments. Add 1.0 part by weight of calcium peroxide powder and 0.3 parts by weight of the polymer interface dispersant obtained in Preparation Example 2 under stirring to form a preloaded material. Spray process water to adjust the moisture content of the preloaded material to 20%. After continuous mixing for 20 minutes, let it stand statically to obtain preloaded straw. Take 150 parts by weight of livestock and poultry manure, i.e. fresh pig manure, and add 0.5 parts by weight of citric acid monohydrate, 1.0 part by weight of ferrous sulfate heptahydrate and 1.0 part by weight of superphosphate in sequence. Stir continuously for 20 minutes to obtain a manure mixture. Adjust the final pH value of the manure mixture to 6.5 to obtain conditioned manure. Preloaded straw is mixed with conditioned manure to obtain a blend. The moisture content of the blend is adjusted to 45%. The blend is piled up to obtain a pile. The height of the pile is controlled at 1.0m, and the pile is allowed to start natural heating and fermentation. The temperature data of the pile is monitored. When the preset fermentation conditions are met, that is, when the temperature in the core area of ​​the pile rises naturally for the first time and reaches 50°C, the pile is turned over using a high-pressure water pump and atomizing nozzles mounted on the turning equipment. At the same time, process water is sprayed into the pile to increase the moisture content of the pile to 55%. After increasing the moisture content of the compost pile, the pile is subjected to fermentation and turning operations to undergo a high-temperature fermentation period. After the high-temperature fermentation period lasts for 15 days, the compost pile is aged until it is fully decomposed. When the temperature in the core area of ​​the compost pile drops to ≤5℃ from the ambient temperature, it is considered to be fully decomposed and organic fertilizer is obtained.

[0038] Example 3: This embodiment provides a method for preparing organic fertilizer by co-composting straw and livestock manure, including the following steps: Take 100 parts by weight of dry base straw, i.e., naturally air-dried rice straw, and crush and cut it into 5cm segments. Add 2.0 parts by weight of calcium peroxide powder and 0.5 parts by weight of the polymer interface dispersant obtained in Preparation Example 3 under stirring to form a preloaded material. Spray process water to adjust the moisture content of the preloaded material to 25%. After continuous mixing for 30 minutes, let it stand statically to obtain preloaded straw. Take 250 parts by weight of livestock and poultry manure, i.e. fresh cow manure, and add 1.0 part by weight of citric acid monohydrate, 2.0 parts by weight of ferrous sulfate heptahydrate and 2.0 parts by weight of superphosphate in sequence. Stir continuously for 30 minutes to obtain a manure mixture. Adjust the final pH value of the manure mixture to 7.3 to obtain conditioned manure. Preloaded straw is mixed with conditioned manure to obtain a blend. The moisture content of the blend is adjusted to 50%. The blend is piled up to obtain a pile. The height of the pile is controlled at 1.5m, and the pile is allowed to start natural heating and fermentation. The temperature data of the pile is monitored. When the preset fermentation conditions are met, that is, when the temperature in the core area of ​​the pile rises naturally for the first time and reaches 55°C, the pile is turned over using a high-pressure water pump and atomizing nozzles mounted on the turning equipment. At the same time, process water is sprayed into the pile to increase the moisture content of the pile to 60%. After increasing the moisture content of the compost pile, the pile is subjected to fermentation and turning operations to undergo a high-temperature fermentation period. After the high-temperature fermentation period lasts for 20 days, the compost pile is aged until it is fully decomposed. When the temperature in the core area of ​​the compost pile drops to ≤5℃ from the ambient temperature, it is considered to be fully decomposed and organic fertilizer is obtained.

[0039] Example 4: This embodiment provides a method for preparing organic fertilizer by co-composting straw and livestock manure, including the following steps: Take 100 parts by weight of dry base straw, i.e. naturally air-dried corn straw, and crush and cut it into 4cm segments. Add 1.5 parts by weight of calcium peroxide powder and 0.4 parts by weight of the polymer interface dispersant obtained in Preparation Example 1 under stirring to form a preloaded material. Spray process water to adjust the moisture content of the preloaded material to 22%. After continuous mixing for 25 minutes, let it stand statically to obtain preloaded straw. Take 200 parts by weight of livestock and poultry manure, i.e., fresh chicken manure, and add 0.75 parts by weight of citric acid monohydrate, 1.5 parts by weight of ferrous sulfate heptahydrate and 1.5 parts by weight of superphosphate in sequence. Stir continuously for 25 minutes to obtain a manure mixture. Adjust the final pH value of the manure mixture to 7.0 to obtain conditioned manure. Preloaded straw and conditioned manure are mixed to obtain a blend. The moisture content of the blend is adjusted to 48%. The blend is piled up to obtain a pile. The height of the pile is controlled at 1.2m. The pile is then allowed to start natural heating and fermentation. The temperature data of the pile is monitored. When the preset fermentation conditions are met, namely the fermentation time reaches 72 hours and the temperature in the core area of ​​the pile is below 50°C, the pile is turned over using a high-pressure water pump and atomizing nozzles mounted on the turning equipment. At the same time, process water is sprayed into the pile to increase the moisture content of the pile to 58%. After increasing the moisture content of the compost pile, the pile is kept fermented and turned over to undergo a high-temperature fermentation period. After the high-temperature fermentation period lasts for 18 days, the compost pile is aged until it is fully decomposed. When the temperature in the core area of ​​the compost pile drops to ≤5℃ from the ambient temperature, it is considered to be fully decomposed and organic fertilizer is obtained.

[0040] Example 5: This embodiment provides a method for preparing organic fertilizer by co-composting straw and livestock manure, including the following steps: Take 100 parts by weight of dry base straw, i.e., a mixture of corn straw and wheat straw, and crush and cut it into 4cm segments. Add 1.5 parts by weight of calcium peroxide powder and 0.4 parts by weight of the polymeric interfacial dispersant obtained in Preparation Example 1 under stirring to form a preloaded material. Spray process water to adjust the moisture content of the preloaded material to 22%. After continuous mixing for 25 minutes, let it stand statically to obtain preloaded straw. Take 200 parts by weight of livestock and poultry manure, i.e., a mixture of pig manure and cow manure, and add 0.75 parts by weight of citric acid monohydrate, 1.5 parts by weight of ferrous sulfate heptahydrate and 1.5 parts by weight of superphosphate in sequence. Stir continuously for 25 minutes to obtain a manure mixture. Adjust the final pH value of the manure mixture to 7.0 to obtain conditioned manure. Preloaded straw and conditioned manure are mixed to obtain a blend. The moisture content of the blend is adjusted to 48%. The blend is piled up to obtain a pile. The height of the pile is controlled at 1.2m. The pile is then allowed to start natural heating and fermentation. The temperature data of the pile is monitored. When the preset fermentation conditions are met, that is, when the temperature in the core area of ​​the pile rises naturally for the first time and reaches 52°C, the pile is turned over using a high-pressure water pump and atomizing nozzles mounted on the turning equipment. At the same time, process water is sprayed into the pile to increase the moisture content of the pile to 58%. After increasing the moisture content of the compost pile, the pile is kept fermented and turned over to undergo a high-temperature fermentation period. After the high-temperature fermentation period lasts for 18 days, the compost pile is aged until it is fully decomposed. When the temperature in the core area of ​​the compost pile drops to ≤5℃ from the ambient temperature, it is considered to be fully decomposed and organic fertilizer is obtained.

[0041] Comparative Example 1: Compared with Example 1, the difference is that: instead of adding calcium peroxide powder, polymeric interfacial dispersant, citric acid monohydrate, ferrous sulfate heptahydrate and superphosphate, dry-based straw, i.e., naturally air-dried corn stalks, is directly mixed with livestock and poultry manure, i.e., fresh chicken manure, to obtain a blend. The moisture content of the blend is adjusted directly to 58%, and the blend is piled up to obtain a pile body. Process water is not sprayed into the pile body to increase the moisture content of the pile body during the process. The rest of the preparation steps are the same.

[0042] Comparative Example 2: Compared with Example 1, the difference is that: instead of performing distributed preloading and conditioning treatment, calcium peroxide powder, polymeric interfacial dispersant, citric acid monohydrate, ferrous sulfate heptahydrate, superphosphate, dry straw (i.e., naturally air-dried corn stalks), and livestock manure (i.e., fresh chicken manure) are all mixed at once to obtain a blend. The moisture content of the blend is adjusted directly to 58%, and the blend is piled up to obtain a pile body. Process water is not sprayed into the pile body to increase the moisture content of the pile body during the process. The remaining preparation steps are the same.

[0043] Comparative Example 3: Compared with Example 1, the difference is that after mixing the preloaded straw with the conditioned manure to obtain the blend, the moisture content of the blend is adjusted directly to 58%, and when the preset fermentation conditions are met, the operation of spraying process water into the pile to increase the moisture content of the pile is not performed. The rest of the preparation steps are the same.

[0044] Comparative Example 4: Compared with Example 1, the difference is that calcium peroxide powder and polymeric interfacial dispersant are not added in the process of preparing preloaded straw, while the rest of the preparation steps are the same.

[0045] Comparative Example 5: Compared with Example 1, the difference is that citric acid monohydrate, ferrous sulfate heptahydrate, and superphosphate are not added during the preparation of conditioned manure, and the pH value of the livestock and poultry manure (i.e., fresh chicken manure) is not adjusted independently. All other preparation steps are the same.

[0046] Comparative Example 6: Compared with Example 4, the difference is that when the preset fermentation conditions are met, i.e. the pile fermentation time reaches 72 hours and the temperature of the core area of ​​the pile is below 50°C, the pile is not turned over or thrown, and process water is not sprayed into the pile to increase the moisture content of the pile. Instead, it is allowed to ferment naturally. The rest of the preparation steps are the same.

[0047] Test Example 1: Naturally grown corn stalks were taken as test subject A; naturally air-dried corn stalks that were crushed and cut to 4cm were mixed with only calcium peroxide powder and moistened with water to 22% before being placed as test subject B; pre-loaded stalks prepared in Example 1 were extracted as test subject C.

[0048] The three test objects were placed in a forced-air drying oven and dried at 65°C until constant weight. After being removed, they were ground using a small laboratory grinder and then passed through a 100-mesh standard sieve. The powder that passed through the sieve was collected and kept as the sample to be tested.

[0049] Each group of sample powders was weighed, spread on a sample-carrying glass plate, and placed in an X-ray diffractometer for scanning. The scanning source was set to Cu-Kα rays, the tube voltage to 40 kV, the tube current to 40 mA, the scanning angle 2θ to be between 5° and 40°, and the scanning rate to 2° / min. After the test, the main diffraction peak and the background scattering data of the amorphous region were extracted, and the relative crystallinity of the cellulose sample was calculated using an empirical formula.

[0050] Take 2 mg of each group of sample powder, and mix and grind them evenly with 200 mg of dried and dehydrated potassium bromide powder in an agate mortar. Transfer the mixture to a tablet press mold and press it into a translucent sheet under a pressure of 15 MPa. Place the sheet in the optical path of a Fourier transform infrared spectrometer and set the scanning wavenumber range to 4000 cm⁻¹. -1 Up to 400cm -1 The resolution is 4cm. -1 The scan was performed 32 times, and the infrared spectral curves of the corresponding samples were recorded. 1510 cm⁻¹ was extracted. -1 and 1050cm -1 The relative transmittance value at the wavenumber position.

[0051] Table 1. Crystallinity and Infrared Transmittance Test Data for Each Test Object

[0052] Based on the data in Table 1 and in conjunction with Figure 1 The X-ray diffraction pattern shown indicates that test subject A, representing native corn stalks, exhibits a sharp diffraction peak around 22.5°, with a cellulose crystallinity of 59.27%. Meanwhile, as shown in the X-ray diffraction pattern... Figure 2 As shown, the object is 1510cm. -1 and 1050cm -1 The relatively low transmittance at the wavenumber positions, at 31.42% and 24.83% respectively, indicates that the aromatic ring skeleton and glycosidic bonds inside the native lignocellulose maintain an intact and dense structure.

[0053] The intensity of the main X-ray diffraction peak of test object B, which only had calcium peroxide added, decreased slightly, corresponding to a crystallinity of 55.14%. The transmittance at the two infrared characteristic peak positions increased slightly to 38.65% and 35.11%, reflecting that calcium peroxide powder alone can only cause limited oxidative erosion on the surface of straw under moisture conditions, and it is difficult to deeply destroy its structure.

[0054] According to the test object C obtained in Example 1, Figure 1 and Figure 2 The peak morphology in the X-ray diffraction pattern shows that the 22.5° main diffraction peak is significantly broadened and flattened, indicating that the crystallinity of cellulose has decreased to 43.58%. Figure 2 The 1510 cm⁻¹ corresponding to the lignin aromatic ring skeleton vibration -1 Position and corresponding 1050 cm of stretching vibration of cellulose COC -1 The two absorption valleys at the location became shallower, and the transmittance increased to 65.73% and 59.42%, respectively.

[0055] The aforementioned experimental phenomena, combined with test data, indicate that after the addition of a polymeric interfacial dispersant, calcium peroxide can penetrate into the internal pores of lignocellulose and undergo localized hydrolysis through its interfacial activity regulation. The oxidation reaction generated in this process causes partial ring-opening breakage of the aromatic skeleton and amorphous transformation of the cellulose crystalline region. This structural dissociation can increase the attachment sites for aerobic microorganisms during subsequent pile fermentation.

[0056] Test Example 2: The composting fermentation process of the blends from Examples 1, 4, and Comparative Example 3 was selected as the test objects for macroscopic composting microenvironment. Meanwhile, the pre-loaded straw obtained in Example 1 and untreated virgin corn straw were selected as the test objects for microscopic thermodynamic analysis.

[0057] The miniature probe of the portable oxygen detector and the thermocouple temperature sensor were inserted to a depth of 0.6 m into the core region of each macroscopic test object. The interstitial oxygen concentration and core temperature were recorded 24 hours after reactor construction to assess the impact of initial moisture content on reactor aeration.

[0058] Continuously monitor the status data of each of the above-mentioned piles. Before the pre-set fermentation conditions in Examples 1 and 4 are met, and before the turning and atomized spraying of process water into the piles, record the data before triggering. Sixty minutes after the water spraying operation, record the data after triggering again. For Comparative Example 3, record reference data synchronously at the corresponding time points.

[0059] Weigh 15 mg of each powder sample of the microscopic thermodynamic analysis test object and spread it evenly in the alumina test crucible of the synchronous thermal analyzer. Set the instrument to heat up to 50°C and maintain a constant temperature. Inject a quantitative amount of trace liquid water into the sample chamber through the instrument's inlet and record the changes in differential scanning calorimetry heat flow signal data before and after water addition to capture the heat fluctuation amplitude caused by the hydrolysis reaction.

[0060] Table 2. Oxygen concentration and temperature data in the core area of ​​each test pile at different fermentation stages

[0061] According to the data in Table 2, the oxygen concentration in the core area of ​​Comparative Example 3 after 24 hours of pile building was 8.53%, lower than 13.82% in Example 1 and 16.15% in Example 4. The aforementioned macroscopic monitoring data indicate that maintaining a low moisture content in the early stages of pile building helps maintain the physical aeration porosity within the material, preventing excessive moisture content from causing air channel blockage and deep oxygen deficiency. When the pile met the preset fermentation conditions and the process water was atomized and sprayed into the pile, the oxygen concentration and temperature in the core areas of Examples 1 and 4 both increased. Compared to the monitoring performance of Comparative Example 3 at the same time point, the materials in both examples exhibited a greater temperature rise and a higher oxygen recovery level.

[0062] Combination Figure 3 As shown in the differential scanning calorimetry (DSC) peak spectrum, the pre-loaded straw prepared in Example 1 exhibits a steep exothermic peak immediately after the addition of water, while the spectrum curve of the native corn straw remains flat, showing no heat fluctuation. (Refer to...) Figure 4 The gas chromatograms shown indicate that the gas sample collected in Example 1 exhibited an extremely high response signal peak at the retention time corresponding to oxygen, while the sample in Comparative Example 3 showed a very weak peak response at the same position.

[0063] The variation characteristics of the aforementioned macroscopic parameters and the microscopic peak patterns corroborate each other, confirming that the phased water control and condition-triggered water replenishment steps employed in this invention can precisely induce the hydrolysis reaction of calcium peroxide particles that have seeped into the pores of the straw. The active oxygen and chemical heat released by this reaction not only directly improve the microaerobic fermentation environment but also replenish the initial heat deficit from a physicochemical perspective, enabling the material to start up smoothly and maintain a high-temperature fermentation period even under unfavorable conditions of slow temperature rise.

[0064] Test Example 3: The composting fermentation processes of the blends prepared in Examples 1 to 3, as well as Comparative Examples 1, 2, 3 and 6, were selected as test subjects, and all test subjects were tested in the same open-air environment.

[0065] Armored thermocouple temperature sensors are evenly distributed at the geometric center and around the perimeter of each test object pile, and the sensor data lines are connected to a multi-channel data acquisition instrument.

[0066] Start the data acquisition program, set the acquisition frequency to record temperature data once every 2 hours, record the time span from the initial room temperature state to the first natural rise in the core area of ​​each test object to 50℃, and record the measured time span as the start-up heating time.

[0067] The fermentation temperature change process of each test object pile was continuously monitored, and the number of consecutive days in which the core area temperature was maintained above 50℃ was counted and recorded as the number of days of high-temperature fermentation period.

[0068] The temperature of the core area of ​​the reactor and the ambient temperature are measured daily. When the temperature of the core area drops to no more than 5°C and the temperature difference with the ambient temperature is no more than 5°C, the maturation stage is considered complete and recording is stopped. The total time from the start of the reactor construction to the determination of the completion of the maturation stage is calculated and recorded as the total maturation cycle.

[0069] Table 3. Statistical data on start-up heating time and fermentation cycle for each test subject

[0070] According to the data in Table 3, Comparative Example 1 used the conventional method of directly mixing dry straw with livestock manure and directly adjusting the moisture content to a high level. Its start-up heating time was recorded as 114.6 hours, the number of days the high-temperature fermentation period was maintained was 8.5 days, and the total maturation period reached 45.4 days. Comparative Example 3 used the conditioning material of this invention, but skipped the staged water control operation and directly set the pile moisture content to 58%, with a corresponding start-up heating time of 96.8 hours.

[0071] The aforementioned operational data indicates that setting a higher moisture content in the initial stage of composting occupies the internal pores of the material, creating a liquid-phase barrier effect that reduces oxygen mass transfer efficiency. This leads to limited reproduction of aerobic microorganisms in the early stages, macroscopically manifested as a prolonged start-up time. Comparative Example 2, which involved mixing all reagents at once, showed that the start-up heating time and total composting period increased by 48.8 hours and 14.3 days, respectively, compared to Example 1. The test results reflect that the simultaneous addition of multiple reagents to the mixed system leads to cross-reactions and consumption, weakening the dissociation effect of the pretreatment agents on the dense structure of the straw.

[0072] Combination Figure 5The fermentation temperature dynamic peak morphology shown in Example 1 indicates that the temperature curve initially formed a steeply rising wave, followed by a broad-amplitude high-temperature main peak in the middle section. This peak morphology is consistent with the statistical data in Table 3, which shows a shortened start-up heating time of 38.5 hours and a high-temperature period maintained for 19.2 days. This correspondence confirms that the phased low-moisture pile-building operation combined with pre-loading treatment established a suitable start-up environment and carbon source supply for the microbial community.

[0073] Referring to the peak morphology of Comparative Example 6, under test conditions of slow start-up and no external water injection intervention, its core temperature curve showed a low and flat trend, without a significant high-temperature maintenance peak. In Example 1, after meeting the preset fermentation conditions and performing atomized spraying of process water into the pile, a compensation mechanism for the release of oxygen and heat from the hydrolysis of calcium peroxide was triggered. This mechanism enabled the pile to overcome the temperature rise resistance and enter a stable aerobic fermentation stage, thereby accelerating the decomposition of internal organic matter and ultimately shortening the total fermentation cycle for determining completion of decomposition to 26.5 days.

[0074] Test Example 4: Organic fertilizer products from Example 1, Comparative Examples 1, 2, and 4 after fermentation were extracted as test subjects, and the original blends from the initial stage of pile building for each test subject were obtained as baseline references.

[0075] Each test object was placed in a forced-air drying oven and dried until its mass was constant. After being pulverized using a laboratory pulverizer, it was passed through a standard test sieve, and the powder that passed through the sieve was collected as the test sample.

[0076] Weigh a certain amount of the sample to be tested and place it into the digestion vessel of a microwave digester. Add a neutral detergent solution and heat to boiling. Then perform a vacuum filtration and washing operation. Dry the obtained residue and weigh it to obtain the mass of the neutral detergent fiber.

[0077] Neutral detergent fibers were boiled with an acidic detergent solution, and after filtration, washing, drying and weighing, the mass of the acidic detergent fibers was obtained. The residual amount of hemicellulose was determined by calculating the mass difference between the neutral detergent fibers and the acidic detergent fibers.

[0078] A 72% sulfuric acid solution was added to the acid-washed fiber residue to initiate a hydrolysis reaction. The undissolved residue was filtered, washed, dried, and weighed, then placed in a muffle furnace for ashing. The residual cellulose was calculated based on the mass loss before and after ashing, and the residual lignin was calculated by deducting the ash mass from the ashing residue.

[0079] Based on the initial mass of the corresponding components in the original blend, the degradation rates of hemicellulose, cellulose, and lignin in each test object were calculated. Simultaneously, a portion of the test sample was placed in a thermogravimetric analyzer and heated to 600℃ at a fixed heating rate under a nitrogen atmosphere. The rate of mass change with temperature was continuously recorded, and the micro-thermogravimetric peak spectrum was obtained.

[0080] Table 4. Degradation rate data of recalcitrant straw components in the finished products of each test subject

[0081] According to the data in Table 4, the hemicellulose degradation rate in Comparative Example 1 was 42.15%, the cellulose degradation rate was 31.84%, and the lignin degradation rate was 12.06%. This test subject was not pretreated, and the corresponding low-level data reflects the strong anti-degradation characteristics of the lignocellulose structure of the native straw. Comparative Example 4, without the addition of calcium peroxide powder and polymeric interfacial dispersant, showed degradation rates similar to those of Comparative Example 1, indicating that simply adjusting moisture and mechanically turning the straw is insufficient to thoroughly destroy its skeleton.

[0082] Comparative Example 2 involved mixing all reagents with the main and auxiliary materials in a single step, resulting in hemicellulose and cellulose degradation rates of 56.32% and 44.71%, respectively. While this figure represents a slight increase compared to Comparative Example 1, the increase is limited when compared with the data from Example 1. The aforementioned test results indicate that directly mixing manure conditioning agents with straw pre-loaded agents can easily lead to cross-reactions in complex material systems. This causes reagents such as calcium peroxide to be consumed before breaking down the lignin coating, reducing the effectiveness of targeted treatment.

[0083] Combination Figure 6 The thermogravimetric analysis (TGA) peaks shown correspond to the 280°C region for hemicellulose thermal degradation and the 330°C region for cellulose thermal degradation. The TGA rate peaks of the sample in Example 1 are significantly lower than those in Comparative Examples 1 and 2. The flattening trend of the peak morphology in the TGA indicates that there are fewer recalcitrant macromolecules remaining in the finished product, which corresponds to the higher degradation rate statistics of Example 1 in Table 4. The degradation rates of hemicellulose and cellulose in Example 1 reached 78.41% and 65.29%, respectively.

[0084] The aforementioned data characteristics and peak patterns indicate that the stepwise preloading process combined with a polymeric interfacial dispersant effectively anchors calcium peroxide to the surface of dry straw, preventing non-target contact with other excipients. The anchored calcium peroxide undergoes localized hydrolysis and oxidation within the straw pores, dissociating the lignin shell and exposing the internal cellulose and hemicellulose. This mechanism increases the enzymatic sites of the microbial community during aerobic fermentation, improving the overall decomposition and transformation level of recalcitrant components in the straw.

[0085] Test Example 5: Example 1, Example 2, and Comparative Examples 1, 3, and 5 were selected as test subjects. During the complete fermentation cycle of each test subject, ammonia gas released from the surface of the pile was captured daily using a closed hood method combined with boric acid absorbent. The ammonia volatilization rate was measured and the nitrogen loss rate for the entire cycle was calculated.

[0086] After each test subject has completed fermentation and cooled to ambient temperature, organic fertilizer products from multiple points in each pile are collected and mixed as samples to be tested. Some of the samples are air-dried, ground, and passed through a standard sieve with a pore size of 0.25 mm for physicochemical index determination.

[0087] Weigh 0.5g of the product powder to be tested into a centrifuge tube, add 50mL of sodium pyrophosphate and sodium hydroxide extract in a 1:1 ratio, and shake in a water bath for 24h. After centrifugation, take the supernatant, add potassium dichromate standard solution and concentrated sulfuric acid, and heat to oxidize. Then titrate with ferrous ammonium sulfate standard solution to calculate the humic acid content in the sample.

[0088] Weigh 2.0 g of the sample powder into a centrifuge tube. Use an ammonium acetate solution with a pH of 7.0 for continuous extraction and centrifugation washing to exchange the exchangeable cations in the sample with ammonium ions. Then wash away excess ammonium acetate with ethanol, add magnesium oxide for distillation, absorb the released ammonia gas with boric acid and titrate to determine the cation exchange capacity.

[0089] Weigh 10g of fresh sample and add deionized water at a solid-liquid ratio of 1:10. Extract by shaking at room temperature for 1 hour, then centrifuge and collect the supernatant as the extraction solution. Place 50 rapeseed seeds evenly on filter paper in a petri dish, add 5mL of the extraction solution, and incubate in a dark incubator at 25℃ for 48 hours. Count the number of germinated seeds and measure the root length. Calculate the seed germination index by comparing with the results of deionized water culture.

[0090] Table 5. Measurement data of the physicochemical properties and fertilizer retention efficiency of organic fertilizer products for each test subject

[0091] According to the data in Table 5, the humic acid content of the organic fertilizer product of Comparative Example 1 was 67.85 g / kg, the cation exchange capacity was 31.42 cmol / kg, the total nitrogen loss rate was 42.56%, and the seed germination index was 65.18%. These measurements reflect that conventional direct composting of straw and livestock manure results in a low degree of humification and significant nitrogen loss, with residual phytotoxic substances in the finished product. Comparative Example 5, even without conditioning agents or polymeric dispersants, still achieved a total nitrogen loss rate of 35.19%, indicating that conventional methods are insufficient to intercept the degradation and overflow of nitrogen-containing compounds during the high-temperature fermentation period.

[0092] Combination Figure 7 The ammonia volatilization rate peak morphology shown in the diagram indicates that Comparative Example 1 exhibits a relatively high main peak of ammonia volatilization around day 5 of the early fermentation stage. This period corresponds to the high-temperature and rapid degradation phase of aerobic fermentation, during which some organic nitrogen is ammonified by microorganisms and then released with the hot gas flow. In contrast, the ammonia volatilization curve of Example 1 remains relatively flat, with the main peak broadened and its peak value decreasing. This suppression of the volatilization rate corroborates the results of the total nitrogen loss rate test in Example 1 (reduced to 11.34%) in Table 5.

[0093] In Example 1, the humic acid content and cation exchange capacity of the finished product increased to 148.27 g / kg and 62.15 cmol / kg, respectively, and the seed germination index reached 92.61%. The improved quality indicators and dynamic peak monitoring data indicate that the straw pre-loading and staged water control process, utilizing the targeted cell-wall breaking effect of calcium peroxide to accelerate lignin dissociation, provides a carbon skeleton for humic acid precursors. Simultaneously, the combined use of polymeric interfacial dispersants and microporous structures increases the physicochemical adsorption sites for ammonium nitrogen. This mechanism can capture free ammonia molecules at high temperatures, promoting their participation in the condensation reaction of humic acid within the compost matrix, thereby improving the fertilizer retention and nitrogen fixation capacity and agricultural safety of the finished product.

Claims

1. A method for preparing organic fertilizer by co-composting straw and livestock manure, characterized in that, Includes the following steps: Take dry straw and crush it. Add calcium peroxide powder and polymeric interfacial dispersant under stirring to form a preloaded material. Spray process water to adjust the moisture content of the preloaded material. After mixing, place it statically to obtain preloaded straw. Take livestock and poultry manure, add citric acid monohydrate, ferrous sulfate heptahydrate and superphosphate in sequence, stir and mix to obtain manure mixture, adjust the final pH value of the manure mixture to obtain conditioned manure; The preloaded straw is mixed with the conditioned manure to obtain a blend. The moisture content of the blend is adjusted, the blend is piled up to obtain a pile, and the pile is allowed to start natural heating and fermentation. Monitor the temperature data of the pile, and when the preset fermentation conditions are met, turn the pile over and spray process water into the pile at the same time to increase the moisture content of the pile. After increasing the moisture content of the pile, the pile is subjected to fermentation and turning operations to undergo a high-temperature fermentation period. After the high-temperature fermentation period ends, the pile is aged until it is fully decomposed to produce organic fertilizer.

2. The preparation method according to claim 1, characterized in that, The proportions of each raw material are as follows: 100 parts by weight of the dry-based straw; The livestock and poultry manure is 150-250 parts by weight; The calcium peroxide powder is used in quantities of 1.0-2.0 parts by weight. The polymeric interfacial dispersant is used in amounts of 0.3-0.5 parts by weight. The citric acid monohydrate is 0.5-1.0 parts by weight; The ferrous sulfate heptahydrate is 1.0-2.0 parts by weight; The superphosphate is 1.0-2.0 parts by weight.

3. The preparation method according to claim 1, characterized in that, The dry-based straw is one or a mixture of several of corn straw, wheat straw and rice straw; The livestock and poultry manure is one or a mixture of chicken manure, pig manure and cow manure.

4. The preparation method according to claim 1, characterized in that, When adjusting the moisture content of the preloaded material, the moisture content of the preloaded material is adjusted to between 20% and 25%. When adjusting the final pH value of the fecal mixture, the final pH value of the fecal mixture is adjusted to 6.5 to 7.3; When adjusting the moisture content of the blend, the moisture content of the blend is adjusted to between 45% and 50%. When increasing the moisture content of the pile, the moisture content of the pile is increased to between 55% and 60%.

5. The preparation method according to claim 1, characterized in that, The polymeric interfacial dispersant is modified sodium lignosulfonate, which has a weight-average molecular weight of 11,000–24,000 Da and a sulfonic acid group content of 1.6–2.4 mmol / g.

6. The preparation method according to claim 5, characterized in that, The modified sodium lignin sulfonate is prepared by the following steps: Take 100 parts by weight of black liquor from paper mill softwood sulfite pulping, filter it through a microfiltration membrane with a pore size of 0.1-0.5 μm at room temperature, and collect the clear microfiltrate. Add dilute sulfuric acid solution to the microfiltrate to adjust the pH to 3.0-4.0 to obtain an acid-adjusted solution; Add 1.0-2.0 parts by weight of a 37% formaldehyde solution to the acid-adjusting solution, seal and heat to 85-95℃ for 2.0-3.0 hours to obtain the modified reaction solution; After the modified reaction solution is cooled, it is washed and concentrated using an ultrafiltration membrane with a molecular weight cutoff of 5000-10000 Da. The ultrafiltration retentate is collected and dried to obtain the modified sodium lignosulfonate.

7. The preparation method according to claim 1, characterized in that, When taking and crushing the dry straw, the dry straw is crushed and cut into segments of 3-5 cm. After the process water is injected to adjust the moisture content of the preloaded material, it is mixed continuously for 20-30 minutes before being placed statically. After adding citric acid monohydrate, ferrous sulfate heptahydrate, and superphosphate in sequence, continue stirring for 20–30 minutes.

8. The preparation method according to claim 1, characterized in that, When the blend is piled up to obtain a pile body, the height of the pile body is controlled between 1.0 and 1.5 m; The preset fermentation conditions are as follows: The temperature in the core area of ​​the reactor body rose naturally for the first time and reached 50-55°C. Alternatively, the fermentation time can reach 72 hours and the temperature in the core area of ​​the pile can be below 50°C.

9. The preparation method according to claim 1, characterized in that, The specific method for increasing the moisture content of the pile is as follows: Using a high-pressure water pump and atomizing nozzles mounted on the turning equipment, the process water is atomized and sprayed into the pile during the turning and throwing operation.

10. The preparation method according to claim 1, characterized in that, After the high-temperature fermentation period ends, the pile is aged until it is fully decomposed. When the temperature difference between the core area of ​​the pile and the ambient temperature is ≤5℃, it is determined that the decomposition is complete.

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