Efficient and harmless composting method of livestock and poultry manure based on enzymatic pretreatment

Abstract

This invention discloses a highly efficient and harmless composting method for livestock and poultry manure based on enzymatic pretreatment, belonging to the field of livestock and poultry manure composting technology. It includes two stages: enzymatic pretreatment and dynamic control of composting. The specific steps are as follows: Enzymatic pretreatment: Livestock and poultry manure is mixed with auxiliary materials at a mass ratio of 1:0.5-1:0.8, and the moisture content is adjusted to 55%-65%. A compound enzyme preparation is added, comprising cellulase, xylanase, laccase, and neutral protease, with an enzyme activity ratio ranging from 3:2:1:1.5. This invention significantly improves composting efficiency and material degradation rate through the enzymatic pretreatment stage: Pretreatment of livestock and poultry manure with a compound enzyme preparation containing cellulase, xylanase, laccase, and neutral protease effectively degrades complex organic matter such as cellulose, hemicellulose, lignin, and proteins, achieving a relative cellulose degradation rate of 25%-40%, laying a good foundation for the subsequent composting process and significantly shortening the composting cycle.

Description

Technical Field

[0001] This invention relates to the field of livestock and poultry manure composting technology, and more specifically, to a method for efficient and harmless composting of livestock and poultry manure based on enzymatic pretreatment. Background Technology

[0002] Livestock and poultry manure, as an important component of agricultural waste, can easily cause environmental pollution and resource waste if not properly treated. Composting, as a traditional method for the harmless and resource-oriented treatment of manure, transforms organic matter into stable humus through microbial action, which can be used for soil improvement and plant nutrient supplementation. Currently, common composting technologies mostly employ static composting, trough turning, or forced ventilation, relying on natural fermentation or simple mechanical control to complete the degradation and maturation of organic matter. However, these methods generally suffer from problems such as long composting cycles, high energy consumption, extensive process control, and unstable product quality. In particular, they have low efficiency in treating recalcitrant substances such as cellulose and lignin, limiting the large-scale and efficient application of composting technology.

[0003] While existing technologies have attempted to optimize the composting process by adding microbial agents, adjusting the carbon-nitrogen ratio, or improving aeration methods, the following shortcomings remain: First, insufficient pretreatment methods make it difficult to effectively break down the complex organic structure in livestock and poultry manure, resulting in slow composting start-up and long cycles. Second, the process control lacks real-time feedback and intelligent adjustment, often relying on experience-based operation, which can easily lead to uneven oxygen supply, large temperature fluctuations, and uncontrolled odor emissions. Third, compost products are mostly used in a crude manner, without being graded or developed for high-value purposes based on their physicochemical properties, resulting in low added value. Fourth, there is a lack of adaptive adjustments to the differences in raw materials, insufficient process flexibility, and difficulty in coping with the characteristics of manure from different sources.

[0004] Based on this, the present invention designs a highly efficient and harmless composting method for livestock and poultry manure based on enzymatic hydrolysis pretreatment to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a highly efficient and harmless composting method for livestock and poultry manure based on enzymatic hydrolysis pretreatment, so as to solve the problems mentioned in the background art.

[0006] A highly efficient and harmless composting method for livestock and poultry manure based on enzymatic pretreatment includes two stages: enzymatic pretreatment and dynamic control of composting. The specific steps are as follows: S1. Enzymatic pretreatment: Mix livestock and poultry manure with auxiliary materials at a mass ratio of 1:0.5-1:0.8, adjust the moisture content to 55%-65%, add a compound enzyme preparation, which contains cellulase, xylanase, laccase and neutral protease, with an enzyme activity ratio of 3:2:1:1.5, and the amount added is 0.5%-1.2% of the dry weight of manure. Stir and react for 12-24 hours at pH 6.0-7.5 and temperature 40-50℃. S2. Dynamically Controlled Composting: The pretreated material is transferred to a controllable aeration composting system, which employs intermittent aeration and temperature feedback linkage control. Specifically: S2.1 Heating Stage: When the pile temperature is below 50℃, the heating rate is 0.8-1.2 L / min·m 3 Aerate continuously at the rate for 3-5 days; S2.2 High Temperature Maintenance Stage: When the temperature rises to 50-65℃, switch to intermittent aeration mode, aerate for 10-15 minutes every two hours, and add heat-resistant microbial agents, which include Bacillus subtilis and Thermophilic Lateral Flocculation, at an addition amount of 0.3%-0.6% of the dry weight of the material, and maintain the high temperature period for 8-12 days; S3. Maturation stage: When the temperature drops below 40℃, the turning frequency is adjusted to once every three days until the moisture content of the compost product is ≤30% and the seed germination index is ≥85%.

[0007] Preferably, the composite enzyme preparation in S1 further comprises an immobilized enzyme carrier, which is a composite microsphere of mesoporous silica and sodium alginate with a particle size of 100-300 μm, a porosity of ≥70%, and an enzyme loading rate of ≥80%. The amount of the immobilized enzyme preparation added in S1 is 0.3%-0.8% of the dry weight of the feces, and it can be reused 3-5 times.

[0008] Preferably, the high-temperature resistant microbial agent in S2.2 is added in stages: the first addition is at the end of the heating stage, and the amount added is 40% of the total dosage. The remaining 60% is added in the form of slow-release granules in the middle of the high-temperature stage. The slow-release granules are made of polylactic acid-coated bacteria and continue to release for 7-10 days at temperatures above 50°C. The controllable aeration composting system also integrates an Internet of Things monitoring module to monitor the compost temperature, oxygen concentration and ammonia concentration in real time.

[0009] Preferably, the compound enzyme preparation in S1 is an enzyme combination capable of synergistically degrading cellulose, hemicellulose, lignin and protein in livestock and poultry manure. Its addition is based on enabling the relative degradation rate of cellulose in the pretreated material to reach 25%-40%. The controllable aeration composting system includes, but is not limited to, a trough-type turning and aeration system, a closed reactor system or a membrane-covered aerobic fermentation system, which can adjust the ventilation volume or turning frequency according to the feedback of the pile temperature or oxygen concentration.

[0010] Preferably, the auxiliary materials in S1 include at least one of straw, rice husk, and mushroom residue for adjusting the carbon-nitrogen ratio, and at least one of crushed corn cob and sawdust for adjusting the porosity. The initial carbon-nitrogen ratio of the mixed material is controlled at 20:1-30:1, and the porosity is controlled at 35%-50%.

[0011] Preferably, the dynamic composting stage further includes a closed-loop control step based on Internet of Things (IoT) monitoring: S2.4 Real-time monitoring: Through a sensor network embedded in the reactor body, data on at least temperature, oxygen concentration and ammonia concentration are continuously collected; S2.5 Intelligent Decision-Making: Based on the monitoring data collected in S2.4, the data is input into the control model. The control model is used to determine whether the pile is in the heating, high temperature or cooling stage, and to predict the risk of odor generation and the maturation process. S2.6 Precise Execution: Based on the output instructions of the control model, automatically adjust the aeration strategy, turning frequency, or timing and dosage of microbial agents added in S2.1 to S2.3 to optimize the composting process and ensure that the final product indicators stably reach the predetermined standards.

[0012] Preferably, the relative degradation rate of cellulose in the pretreated material in S1 is quantitatively correlated with the shortening of the total composting cycle in S2: when the relative degradation rate of cellulose is in the range of 25%-40%, compared with the same material without enzymatic pretreatment, the total composting cycle is shortened by 35%-55%. The optimization of the composting process by the closed-loop control is reflected in: while maintaining the pile temperature at 55-65℃ for several days, the cumulative energy consumption per unit material of the aeration system is reduced by 20%-40%.

[0013] Preferably, the method further includes an adaptive pre-step: S0. Raw material characteristic analysis and parameter pre-adjustment: Detect key characteristic indicators of livestock and poultry manure raw materials, including at least antibiotic residue concentration, conductivity and viscosity. The detection method for the key characteristic indicators is as follows: Antibiotic residue concentrations were determined using high performance liquid chromatography-tandem mass spectrometry. Conductivity was measured using a conductivity meter method, referring to the standard method after water extraction of the sample; The viscosity was determined using a rotational viscometer method. S0.1, Adaptive Formulation and Parameters: Based on the test results of S0, dynamically adjust at least one of the following: The type ratio or amount of the compound enzyme preparation described in S1; When the antibiotic residue concentration is detected to be higher than the set threshold, the proportion of laccase in the compound enzyme preparation and / or the total amount of enzyme preparation added shall be increased. When a high cellulose or lignin content is detected, increase the proportion of cellulase or xylanase. When the viscosity of the raw material is too high, the amount of enzyme preparation added should be adjusted accordingly or the enzyme system ratio should be optimized. The initial parameters or intervention thresholds of the control model described in S2; Based on the ammonia generation potential and conductivity data of the raw material, set or dynamically adjust the ammonia concentration intervention threshold, aeration start timing or aeration strategy. Based on the porosity and viscosity of the raw materials, the aeration frequency, duration, and turning strategy during the heating and high-temperature stages were optimized.

[0014] Preferably, the method further includes a step of targeted preparation of high-value compost products: S4. Product Grading and Functionalization: Based on the maturity, particle size, and nutrient content of the final compost product obtained in S3, it is screened and graded. The screening and grading includes: Particle size screening: Using vibrating screens or drum screens, the compost products are divided into at least two grades according to particle size. The first grade consists of fine particles with a particle size of less than 3 mm, and the second grade consists of medium and coarse particles with a particle size between 3 and 10 mm. Maturity grading: Based on seed germination index (GI) and carbon-nitrogen ratio (C / N), compost products are classified into high maturity (GI≥90%, C / N≤20), medium maturity (GI 80%–90%), and low maturity (GI<80%). Nutrient content classification: Based on the total nitrogen, total phosphorus, total potassium and organic matter content, compost products are classified into high nutrient type (N+P2O5+K2O≥8%) and medium and low nutrient type. After screening, the results of the grading process are used in a targeted manner: S4.1 Preparation of soil conditioner: The first-stage product with high decomposition degree, fine particle size and high nutrient content is mixed with mineral carrier and pH adjuster and granulated to prepare granular soil conditioner for improving acidic or compacted soil. S4.2 Preparation of ecological restoration substrate: The second-stage product with moderate decomposition, good water retention and moderate particle size is compounded with root-promoting bacteria, water-retaining materials and structural fibers to prepare a special substrate for ecological restoration of mine slopes or degraded grasslands. The grading criteria for the compost products in step S4 are derived from the stable and traceable composting process data and final product index database obtained through closed-loop control in steps S2 and S3.

[0015] Compared with the prior art, the advantages of this invention are: 1. This invention significantly improves composting efficiency and material degradation rate through an enzymatic pretreatment stage: using a complex enzyme preparation containing cellulase, xylanase, laccase and neutral protease to pretreat livestock and poultry manure can effectively degrade complex organic matter such as cellulose, hemicellulose, lignin and protein, so that the relative degradation rate of cellulose reaches 25%-40%, laying a good foundation for the subsequent composting process and greatly shortening the composting cycle.

[0016] 2. This invention achieves precise optimization of the composting process through dynamic regulation of composting and intelligent closed-loop control: It adopts an IoT-based real-time monitoring and intelligent decision-making system to dynamically adjust aeration, turning, and microbial agent addition strategies according to parameters such as pile temperature, oxygen and ammonia concentration. This ensures stable maintenance during the high-temperature stage, effectively controls odor emissions, and reduces energy consumption by 20%-40%, thereby improving the control precision and stability of the composting process.

[0017] 3. This invention improves resource utilization efficiency through the application of immobilized enzyme preparations and slow-release microbial agents: by using reusable immobilized enzyme carriers and segmented slow-release heat-resistant microbial agents, not only is the amount of enzyme and agent added reduced, but their ability to continue to function in the composting system is also enhanced, thereby improving the sustainability and economy of the composting process.

[0018] 4. This invention achieves personalized and high-value-added transformation through pre-control of raw material adaptability and targeted preparation of high-value products: process parameters are dynamically adjusted according to the characteristics of raw materials, and the compost products are graded and utilized according to their maturity, particle size and other characteristics to prepare high-value products such as soil conditioners and ecological restoration substrates, thereby expanding the application scenarios and market value of compost products.

[0019] 5. This invention enhances the biological function and growth-promoting effect of compost products by introducing bioactive substances such as gibberellic acid: adding gibberellic acid during the composting stage or product compounding process can not only stimulate the activity of beneficial microorganisms in compost, but also enhance the growth-promoting ability of the final product in agriculture and ecological restoration, thereby realizing the functionalization and biological activity enhancement of compost products. Attached Figure Description

[0020] Figure 1 This is a process flow diagram of a highly efficient and harmless composting method for livestock and poultry manure based on enzymatic pretreatment proposed in this invention. Detailed Implementation

[0021] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. 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.

[0022] Example 1: Composting using pig manure as the main raw material S0. Raw material characteristic analysis and parameter pre-tuning: Key characteristics of pig manure raw materials tested included: tetracycline antibiotic residue of 1.2 mg / kg, conductivity of 8.5 mS / cm, and high viscosity. Based on these results, parameters were adjusted accordingly. The proportion of laccase in the S1 compound enzyme preparation is increased by 20% (to enhance the degradation of antibiotics), and the total addition amount is set at 1.0% of the dry weight of feces.

[0023] In S2, the ammonia concentration intervention threshold of the control model is set to a low level to address potential local anaerobic odor problems caused by high viscosity.

[0024] S1. Enzymatic pretreatment: Take 1000 kg of fresh pig manure (dry matter content approximately 25%) and mix it with crushed corn cobs (particle size approximately 2-5 cm) at a mass ratio of 1:0.6, i.e., add 600 kg of corn cobs. Spray an appropriate amount of water to adjust the moisture content of the mixture to 60%. Add a compound enzyme preparation containing cellulase, xylanase, laccase, and neutral protease, with an enzyme activity ratio of 3:2:1.2:1.5, and add 1.0% of the dry weight of the pig manure (250 kg), i.e., 2.5 kg. The enzyme preparation is pre-dissolved in phosphate buffer at pH 7.0 and then sprayed evenly onto the material. Place the material in a stirred reaction chamber with an insulated jacket, maintain the temperature at 45℃ and pH 6.8, and continuously stir for 18 hours. After the reaction, take samples for testing, and the relative degradation rate of cellulose was found to be 32%.

[0025] S2, Dynamically Regulated Composting: The pretreated material is transferred into a trough-type turning and aeration system (trough width 4 m, effective stacking height 1.8 m).

[0026] S2.1 Heating Stage: Initial pile temperature 28℃, continuous aeration initiated at a rate of 1.0 L / min·m 3 Three days later, the temperature at the center of the reactor reached 50°C.

[0027] S2.2 High-Temperature Maintenance Phase: Switch to intermittent aeration mode, aerating for 12 minutes every 2 hours. Simultaneously add a heat-resistant microbial agent (Bacillus subtilis: Thermophilus laterosporus = 1:1, total viable count ≥ 5 × 10^9 CFU / g). This agent is first added when the temperature reaches 50℃, at a rate of 40% of the total dosage (0.5% of the material's dry weight). The remaining 60% of the agent is formulated as polylactic acid-coated slow-release granules (approximately 2 mm in diameter), which are uniformly incorporated into the pile on the 5th day of the high-temperature phase. The pile temperature is monitored in real-time via an IoT module, maintaining a stable temperature of 55-62℃ and ammonia concentration within a safe range (<10 ppm). The high-temperature period lasts for 10 days.

[0028] S2.4-S2.6 Closed-loop control: The sensor network buried in the pile continuously collects data and uploads it to the cloud platform. The control model (based on the fuzzy PID algorithm) dynamically fine-tunes the aeration frequency (adjusted within the range of 10-15 minutes every 2 hours) and the timing of each turning and throwing based on real-time temperature, oxygen (maintained >10%) and ammonia concentration data, thus achieving precise oxygen supply and odor control.

[0029] S3, Maturation Stage: After the high-temperature period ended, the temperature of the compost pile naturally dropped. When the temperature dropped below 40℃, the control system adjusted the turning frequency to once every 3 days. After continuing to pile for 15 days, samples were taken for testing. The moisture content of the compost product was 28%, the seed germination index (GI) was 92%, and the C / N ratio was 18, which met the decomposition standard.

[0030] S4. Targeted preparation of high-value products: The well-rotted compost is sieved and graded: First-stage product (particle size <3 mm, high decomposition, GI=95%): Take 700 kg, mix with 200 kg bentonite, 50 kg limestone powder, appropriate amount of gibberellic acid (GA3, purity ≥90%, addition amount is 50-100 mg / kg based on finished product) and 20 kg binder, granulate and dry at low temperature to obtain granular soil conditioner. This product can not only improve compacted soil, but the gibberellic acid it contains can gently stimulate plant root growth and improve crop stress resistance.

[0031] The second-stage product (particle size 3-10 mm, good water retention): Take 300 kg of the product and mix it evenly with 50 kg of water-retaining agent (polyacrylamide), 100 kg of coconut coir, 5 kg of plant growth-promoting bacteria containing gibberellin secretion ability (such as a certain rhizosphere bacterial ferment), and 10 kg of structural fiber (hemp fiber) to prepare a special substrate for ecological restoration. This substrate is suitable for mine slope restoration. The gibberellin component can work synergistically with the root-promoting bacteria to accelerate the establishment and growth of pioneer plants on barren substrates.

[0032] Example 2: Composting using a mixture of chicken manure and mushroom residue as raw materials S0. Raw material characteristic analysis and parameter pre-tuning: The mixture of chicken manure and mushroom residue showed low antibiotic residue (<0.1 mg / kg), a conductivity of 6.0 mS / cm, and good porosity. Parameter adjustments are as follows: Given the high cellulose content of the raw materials, the proportion of cellulase in the compound enzyme preparation in S1 is increased by 10%.

[0033] The initial C / N ratio is set to 25:1.

[0034] S1. Enzymatic pretreatment: Take 800 kg of chicken manure (30% dry matter content), 400 kg of mushroom residue, and 200 kg of rice husks, mix them in a certain proportion, adjust the moisture content to 58%, and add a composite enzyme preparation containing an immobilized carrier (the carrier is mesoporous silica-sodium alginate microspheres, enzyme loading rate 85%), at an addition amount of 0.6% of the dry weight of the manure (240 kg). React at pH 7.2 and 48℃ for 20 hours. After the reaction, the relative degradation rate of cellulose reached 28%.

[0035] S2, Dynamically Regulated Composting: The material is transferred into a membrane-covered aerobic fermentation system.

[0036] During the warming phase, aeration continued for 4 days until the temperature reached 50℃.

[0037] During the high-temperature phase, intermittent aeration was employed, with microbial agents added in stages. The control model flexibly adjusted the aeration duration based on oxygen concentration feedback to ensure that the high-temperature period (55-60℃) was maintained for 9 days.

[0038] The closed-loop control system effectively reduces aeration energy consumption by 35% compared to the traditional timed aeration mode.

[0039] S3, Maturation Stage: After cooling and 12 days of fermentation, the product has a moisture content of 26% and a GI of 88%.

[0040] S4. Targeted preparation of high-value products: The first-stage fine-particle product is mixed with humic acid, potassium feldspar powder and gibberellic acid (addition amount 0.05%, based on finished product) to prepare a high-end horticultural cultivation substrate that combines soil improvement and growth stimulation functions.

[0041] The second-stage coarse-grained product is used to prepare lightweight substrates for rooftop greening.

[0042] Example 3: Compost mainly composed of cow dung and straw (with the introduction of gibberellic acid) S1. Enzymatic pretreatment: Cow dung was mixed with wheat straw (C / N ratio initially 28:1), and enzymatic pretreatment was performed as in Example 1.

[0043] S2, Dynamically Regulated Composting: In the early stages of composting (when the temperature drops to 45℃), a dilute solution of gibberellic acid (GA3) (concentration of 50 mg / L) is evenly added to the compost pile through a spray system. The amount added is equivalent to adding 5 g of pure gibberellic acid per ton of compost product. The purpose of this is: Utilize the mild environment during the composting stage to avoid the decomposition of gibberellic acid by high temperatures.

[0044] Promotes the activity of beneficial microorganisms: As a plant endogenous hormone, gibberellic acid can also stimulate the metabolic activity of certain functional microorganisms in the composting stage (such as cellulose-degrading bacteria and biocontrol bacteria), further stabilizing compost products and enhancing their biological activity.

[0045] Pre-loaded with bioactive substances: This ensures that the final compost product contains gibberellic acid, which promotes growth. When used as a soil conditioner or seedling substrate, this can promote seed germination and seedling growth.

[0046] The subsequent composting process was similar to that in Example 1. The final compost product had a seed germination index (GI) that was significantly higher than that of the control group without gibberellic acid (95% vs 85%), and when used in seedling trials, it showed a significant improvement in seedling height and root activity.

[0047] Comparative example: The same pig manure raw material as in Example 1 was used, but without enzymatic pretreatment, and the composting process employed a traditional static composting method with timed turning and fixed aeration. The results are as follows: The compost heats up slowly, only entering its high-temperature period on the 7th day.

[0048] Temperatures fluctuate greatly during periods of high temperatures, making it difficult to maintain stability.

[0049] The total composting cycle is as long as 65 days, which is 71% longer than Example 1 (total cycle of 38 days).

[0050] The final product had a moisture content of 35%, a GI of 78%, was not fully decomposed, and had a distinct ammonia odor.

[0051] The products were not graded and utilized for high-value purposes, resulting in low overall quality and added value.

[0052] Summary of experimental results: As can be seen from the above examples and comparative examples, the composting method based on enzymatic pretreatment and dynamic intelligent control provided by this invention can significantly shorten the composting cycle (35%-55%), reduce energy consumption (20%-40%), and stably produce high-quality, harmless compost products. By introducing gibberellic acid, whether in the final product compounding stage or through precise addition during the maturation stage, the biological activity and growth-promoting function of the compost products can be effectively enhanced, achieving efficient, intelligent, and high-value resource utilization of livestock and poultry manure. The method of this invention has strong process controllability, wide product applications, and good environmental, economic, and application prospects.

[0053] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for efficient and harmless composting of livestock and poultry manure based on enzymatic pretreatment, characterized in that, The composting process includes two stages: enzymatic pretreatment and dynamic control. The specific steps are as follows: S1. Enzymatic pretreatment: Mix livestock and poultry manure with auxiliary materials at a mass ratio of 1:0.5-1:0.8, adjust the moisture content to 55%-65%, add a compound enzyme preparation, which contains cellulase, xylanase, laccase and neutral protease, with an enzyme activity ratio of 3:2:1:1.5, and the amount added is 0.5%-1.2% of the dry weight of manure. Stir and react for 12-24 hours at pH 6.0-7.5 and temperature 40-50℃. S2. Dynamically Controlled Composting: The pretreated material is transferred to a controllable aeration composting system, which employs intermittent aeration and temperature feedback linkage control. Specifically: S2.1 Heating Stage: When the pile temperature is below 50℃, the heating rate is 0.8-1.2 L / min·m 3 Aerate continuously at the rate for 3-5 days; S2.2 High Temperature Maintenance Stage: When the temperature rises to 50-65℃, switch to intermittent aeration mode, aerate for 10-15 minutes every two hours, and add heat-resistant microbial agents, which include Bacillus subtilis and Thermophilic Lateral Flocculation, at an addition amount of 0.3%-0.6% of the dry weight of the material, and maintain the high temperature period for 8-12 days; S3. Maturation stage: When the temperature drops below 40℃, the turning frequency is adjusted to once every three days until the moisture content of the compost product is ≤30% and the seed germination index is ≥85%.

2. The method for efficient and harmless composting of livestock and poultry manure based on enzymatic pretreatment according to claim 1, characterized in that, The composite enzyme preparation in S1 further includes an immobilized enzyme carrier, which is a composite microsphere of mesoporous silica and sodium alginate with a particle size of 100-300 μm, a porosity of ≥70%, and an enzyme loading rate of ≥80%. The amount of this immobilized enzyme preparation added to S1 is 0.3%-0.8% of the dry weight of the feces, and it can be reused 3-5 times.

3. The method for efficient and harmless composting of livestock and poultry manure based on enzymatic pretreatment according to claim 1, characterized in that, The high-temperature resistant microbial agent in S2.2 is added in stages: the first addition is at the end of the heating stage, and the amount added is 40% of the total dosage. The remaining 60% is added in the form of slow-release granules in the middle of the high-temperature stage. The slow-release granules are made of polylactic acid-coated bacteria and continue to release for 7-10 days at temperatures above 50°C. The controllable aeration composting system also integrates an Internet of Things monitoring module to monitor the compost temperature, oxygen concentration and ammonia concentration in real time.

4. The method for efficient and harmless composting of livestock and poultry manure based on enzymatic pretreatment according to claim 1, characterized in that, The composite enzyme preparation in S1 is a combination of enzymes that can synergistically degrade cellulose, hemicellulose, lignin and protein in livestock and poultry manure. Its addition is based on the requirement that the relative degradation rate of cellulose in the pretreated material reaches 25%-40%. The controllable aeration composting system includes, but is not limited to, a trough-type turning and aeration system, a closed reactor system or a membrane-covered aerobic fermentation system, which can adjust the ventilation volume or turning frequency according to the feedback of the pile temperature or oxygen concentration.

5. The method for efficient and harmless composting of livestock and poultry manure based on enzymatic pretreatment according to claim 4, characterized in that, The auxiliary materials in S1 include at least one of straw, rice husk, and mushroom residue for adjusting the carbon-nitrogen ratio, and at least one of crushed corn cob and sawdust for adjusting the porosity. The initial carbon-nitrogen ratio of the mixed material is controlled at 20:1-30:1, and the porosity is controlled at 35%-50%.

6. The method for efficient and harmless composting of livestock and poultry manure based on enzymatic pretreatment according to claim 4, characterized in that, The dynamic composting stage also includes a closed-loop control step based on Internet of Things (IoT) monitoring: S2.4 Real-time monitoring: Through a sensor network embedded in the reactor body, data on at least temperature, oxygen concentration and ammonia concentration are continuously collected; S2.5 Intelligent Decision-Making: Based on the monitoring data collected in S2.4, the data is input into the control model. The control model is used to determine whether the pile is in the heating, high temperature or cooling stage, and to predict the risk of odor generation and the maturation process. S2.6 Precise Execution: Based on the output instructions of the control model, automatically adjust the aeration strategy, turning frequency, or timing and dosage of microbial agents added in S2.1 to S2.3 to optimize the composting process and ensure that the final product indicators stably reach the predetermined standards.

7. The method for efficient and harmless composting of livestock and poultry manure based on enzymatic pretreatment according to claim 6, characterized in that, The relative degradation rate of cellulose in the pretreated material in S1 is quantitatively correlated with the shortening of the total composting cycle in S2: when the relative degradation rate of cellulose is in the range of 25%-40%, compared with the same material without enzymatic pretreatment, the total composting cycle is shortened by 35%-55%. The optimization of the composting process by the closed-loop control is reflected in: while maintaining the pile temperature at 55-65℃ for several days, the cumulative energy consumption per unit material of the aeration system is reduced by 20%-40%.

8. The method for efficient and harmless composting of livestock and poultry manure based on enzymatic pretreatment according to claim 6, characterized in that, The method further includes an adaptive pre-step: S0. Raw material characteristic analysis and parameter pre-adjustment: Detect key characteristic indicators of livestock and poultry manure raw materials, including at least antibiotic residue concentration, conductivity and viscosity. The detection method for the key characteristic indicators is as follows: Antibiotic residue concentrations were determined using high performance liquid chromatography-tandem mass spectrometry. Conductivity was measured using a conductivity meter method, referring to the standard method after water extraction of the sample; The viscosity was determined using a rotational viscometer method. S0.1, Adaptive Formulation and Parameters: Based on the test results of S0, dynamically adjust at least one of the following: The type ratio or amount of the compound enzyme preparation described in S1; When the antibiotic residue concentration is detected to be higher than the set threshold, the proportion of laccase in the compound enzyme preparation and / or the total amount of enzyme preparation added shall be increased. When a high cellulose or lignin content is detected, increase the proportion of cellulase or xylanase. When the viscosity of the raw material is too high, the amount of enzyme preparation added should be adjusted accordingly or the enzyme system ratio should be optimized. The initial parameters or intervention thresholds of the control model described in S2; Based on the ammonia generation potential and conductivity data of the raw material, set or dynamically adjust the ammonia concentration intervention threshold, aeration start timing or aeration strategy. Based on the porosity and viscosity of the raw materials, the aeration frequency, duration, and turning strategy during the heating and high-temperature stages were optimized.

9. A method for efficient and harmless composting of livestock and poultry manure based on enzymatic pretreatment according to claim 8, characterized in that, The method also includes a step for the targeted preparation of high-value compost products: S4. Product Grading and Functionalization: Based on the maturity, particle size, and nutrient content of the final compost product obtained in S3, it is screened and graded. The screening and grading includes: Particle size screening: Using vibrating screens or drum screens, the compost products are divided into at least two grades according to particle size. The first grade consists of fine particles with a particle size of less than 3 mm, and the second grade consists of medium and coarse particles with a particle size between 3 and 10 mm. Maturity grading: Based on seed germination index (GI) and carbon-nitrogen ratio (C / N), compost products are classified into high maturity (GI≥90%, C / N≤20), medium maturity (GI 80%–90%), and low maturity (GI<80%). Nutrient content classification: Based on the total nitrogen, total phosphorus, total potassium and organic matter content, compost products are classified into high nutrient type (N+P2O5+K2O≥8%) and medium and low nutrient type. After screening, the results of the grading process are used in a targeted manner: S4.1 Preparation of soil conditioner: The first-stage product with high decomposition degree, fine particle size and high nutrient content is mixed with mineral carrier and pH adjuster and granulated to prepare granular soil conditioner for improving acidic or compacted soil. S4.2 Preparation of ecological restoration substrate: The second-stage product with moderate decomposition, good water retention and moderate particle size is compounded with root-promoting bacteria, water-retaining materials and structural fibers to prepare a special substrate for ecological restoration of mine slopes or degraded grasslands. The grading criteria for the compost products in step S4 are derived from the stable and traceable composting process data and final product index database obtained through closed-loop control in steps S2 and S3.

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