High-efficiency composting method of cow dung organic fertilizer based on plateau alpine low-temperature oxygen-deficient environment

Abstract

The invention discloses a high-efficiency composting method of a cow dung organic fertilizer based on a plateau alpine low-temperature anoxic environment, which comprises the following steps: mixing a fermentation main material, a fermentation auxiliary material, a low-temperature complex microbial inoculant and a fermentation aid, and adjusting the water content and carbon nitrogen ratio of the whole material; covering with a nano-film for aerobic fermentation; carrying out aging treatment; and detecting quality, packaging and the like. The method has the remarkable effects that the technical advantages of low-temperature fungicide, intermittent dynamic aerobic composting, nano-film covering, fermentation and the like are integrated, and the problems of low composting efficiency, nutrient loss, environmental pollution and the like in a plateau environment are solved.

Description

Technical Field

[0001] This invention relates to the field of organic waste resource utilization technology, specifically to a high-efficiency composting method for cow manure organic fertilizer suitable for the high-altitude and oxygen-deficient environment on the eastern edge of the Qinghai-Tibet Plateau (such as Ganzi Tibetan Autonomous Prefecture in Sichuan Province). Background Technology

[0002] Animal husbandry is well-developed in plateau regions, but traditional composting technology faces severe challenges. The current "DB5133 / T 75-2023 Technical Specification for Yak Manure Treatment" stipulates an aerobic fermentation cycle of 60-90 days, and requires maintaining a high temperature of 55-65℃ for ≥5 days, which is significantly inconsistent with the low-temperature environment of plateaus.

[0003] The bottlenecks of traditional composting technology are as follows: 1. Low efficiency: Natural composting depends on ambient temperature. In winter (-10℃), the fermentation cycle is extended to more than 120 days, making it difficult to meet the harmlessness standard (for example, Salmonella killing requires ≥55℃ for 72 hours).

[0004] 2. Severe nutrient loss: Traditional compost has a nitrogen loss rate of 35%-45% and a humic acid content of only 1.2%-2.5%, far below the standard for commercial organic fertilizer (NY525-2021 requires organic matter ≥30%).

[0005] 3. Significant environmental risks: The mechanized composting coverage rate in the whole prefecture is less than 15%, and the COD concentration of leachate generated from open-air storage is as high as 8000-12000 mg / L, exceeding the "Standards for Irrigation Water Quality" (GB5084) by 3-5 times. The ammonia concentration reaches 25-30 mg / m3, exceeding the "Emission Standard for Odor Pollutants" (GB14554) by 2 times.

[0006] In summary, the limitations of existing technologies are as follows: Poor compatibility of microbial agents: Commercially available microbial agents have a growth rate of only 0.02 h at temperatures below 10℃. - 1. This causes a 3-5 day delay in the start of fermentation.

[0007] Insufficient intelligent equipment: Most existing composting equipment are simple turning machines, which cannot achieve precise temperature control (±2℃) and dynamic ventilation, and labor costs account for 42% (Ganzi Prefecture Agricultural Mechanization Development Report).

[0008] Lack of supply chain integration: The co-processing rate of agricultural waste such as cow dung and barley straw is less than 20%, and transportation costs account for more than 35% of the total cost.

[0009] Ganzi Tibetan Autonomous Prefecture has clearly mandated that by 2025, organic fertilizer should replace chemical fertilizer on 1.1 million mu (approximately 73,333 hectares) of land, and the resource utilization rate of livestock and poultry manure should reach 85%. Organic fertilizer products must meet the "Ganzi Prefecture Organic Industry Standard System" (e.g., heavy metal Cd ≤ 0.3 mg / kg, fecal coliforms ≤ 100 CFU / g). Therefore, traditional composting technologies can no longer meet policy requirements, and there is an urgent need to develop efficient composting systems adapted to the plateau environment.

[0010] To address the problems of long fermentation cycles and low removal rates of antibiotic resistance genes in existing technologies, this invention overcomes the limitations of low-temperature environments through innovation in microbial agents, integration of intelligent equipment, and process optimization. Summary of the Invention

[0011] To address the shortcomings of existing technologies, the purpose of this invention is to provide a highly efficient composting method for cow manure organic fertilizer in high-altitude, cold, low-temperature, and oxygen-deficient environments. By integrating low-temperature fermentation agents, intelligent temperature control systems, and dynamic process regulation technologies, this method can achieve the harmless treatment and resource utilization of livestock manure in high-altitude areas.

[0012] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A highly efficient composting method for cow manure organic fertilizer in a high-altitude, cold, low-temperature, and oxygen-deficient environment comprises the following steps: Step 1, Raw material pretreatment: Mix the main fermentation material, fermentation auxiliary material, low-temperature compound microbial agent, and fermentation aid, and adjust the overall material moisture content and carbon-nitrogen ratio; Step 2: Aerobic fermentation covered by nanomembrane: Step 2.1: Stack the mixed raw materials into a trapezoidal stack and cover the surface with a nanofilm; Step 2.2: Install a ventilation system at the bottom of the trapezoidal stack; Step 2.3: Fermentation is carried out, and dynamic turning is performed according to the predetermined turning strategy based on the core temperature of the pile, and ventilation is performed according to the predetermined ventilation strategy. Step 3, Aging Treatment: Transfer the fermented material to an insulated aging box for aging treatment; Step 4, Quality Inspection and Packaging: The aged material is tested for maturity. If the test results are satisfactory, the material is crushed, granulated and coated to obtain organic fertilizer.

[0013] Furthermore, the main fermentation materials are fresh cow dung and straw powder, with the straw powder having a length of 2-3 cm. The fermentation auxiliary materials include rice bran, bone meal, and urea. The weight ratio of the fresh cow dung, straw powder, rice bran, bone meal, and urea is 70:25:3:1.5:0.5.

[0014] Furthermore, the low-temperature compound microbial agent consists of Lactobacillus plantarum, Bacillus subtilis refractory, and Aspergillus niger, with a bacterial count ratio of 0.5:1.0:0.8.

[0015] Furthermore, the process for obtaining the low-temperature compound microbial agent is as follows: Soil samples were taken from the alpine meadows; Microbial isolation and purification were performed on the sampled soil; The isolated and purified microorganisms were subjected to low-temperature acclimatization screening, and the synergistic effect was verified to obtain cold-resistant strains; Gene sequencing was performed on the obtained cold-resistant strains to obtain the formulated low-temperature compound bacterial agent.

[0016] Furthermore, the fermentation aid is a complex of sucrose isobutyrate acetate and dicosylamine.

[0017] Furthermore, the moisture content of the overall material described in step 1 is 55%-60%, and the carbon-to-nitrogen ratio is 25:1.

[0018] Furthermore, the ventilation system includes a controller and a ventilation actuator. The input terminal group of the controller is connected to a temperature sensor for detecting the core temperature of the material, an oxygen sensor for detecting the oxygen content of the material, and a moisture sensor for detecting the moisture content of the material. The controller controls the ventilation actuator using a control model based on the detected core temperature, oxygen content, and moisture content of the material. The expression for the control model is: in, , These are the weighting coefficients. b For bias terms, , These represent the oxygen content and moisture content of the material in the trapezoidal stack, respectively.

[0019] Furthermore, in step 2.3, during primary fermentation, the core temperature is controlled at 65-70℃ and maintained for 7-10 days.

[0020] Furthermore, in step 2.3, the predetermined heap turning strategy is as follows: When the fermentation temperature is between 5-25℃, turn the pile over once on the first day; When the fermentation temperature rises to 65-75℃ and remains stable above 65℃ for more than 48 hours, turn the pile over once every 2 days. When the fermentation temperature drops to 30-40℃, turn the pile over once every 7 days; The predetermined ventilation strategy is as follows: When the fermentation temperature is between 5-25℃, use 0.5~1.5m3 Continuous ventilation at a rate of / min·ton; When the fermentation temperature rises to 65-75℃, use 0.2~0.5m 3 Intermittent ventilation was carried out at a rate of / min·ton, with a ventilation time of 5min and an interval of 10min. When the fermentation temperature drops to 30-40℃, ventilation should be stopped.

[0021] Furthermore, the specific process of the aging treatment is as follows: Transfer the primary fermented material to an insulated aging box, pile it up to a height of 1.2m, and allow natural ventilation; The aging temperature was maintained at 30-40℃, and the pile was turned over once every 7 days for 3-4 weeks. The aging process is complete when the temperature of the pile drops below 30°C and the germination index is ≥85%.

[0022] The significant effects of this invention are: 1. High-altitude low-temperature microbial agent compound technology: Cold-resistant strains are obtained through targeted domestication, and by combining cold-resistant strains (Lactobacillus plantarum, Bacillus subtilis, Aspergillus niger) with fermentation aids, composting can start up quickly even when the ambient temperature is as low as 5℃, and the temperature can rise to above 55℃ within 48 hours, solving the problem of "difficult start-up" of high-altitude composting.

[0023] 2. Nanofilm Intelligent Composting System Integration: Combining molecular membrane covering and controllable ventilation, this system achieves integrated heat preservation, moisture retention, and deodorization during the composting process. Field tests show that the system can maintain the core temperature above 60℃ even in high-altitude winters (-10℃), shortening the fermentation cycle by 30%.

[0024] 3. Turning-Ventilation Synergistic Regulation Mechanism: The turning frequency is designed based on temperature changes and ARGs removal kinetics, breaking through the traditional fixed-time turning mode. High-frequency turning (2 days / time) increases humus content (1.91%-7.45%) while effectively interrupting the horizontal gene transfer chain of ARGs through the specific degradation of resistance genes such as ermB and tetW during the high-temperature period.

[0025] 4. High-efficiency resource utilization model for waste: This invention not only processes cow dung, but also synergistically utilizes agricultural waste such as straw and rice bran, with an overall conversion rate exceeding 99%. When the produced organic fertilizer is applied to degraded grasslands, soil organic matter increases by 0.3%-0.5% annually. Attached Figure Description

[0026] Figure 1 This is a process flow diagram of the present invention; Figure 2 This is a flowchart of the screening process for low-temperature compound microbial agents; Figure 3This is a schematic cross-sectional view of microcarrier microspheres; Figure 4 This is a schematic diagram of the structure of an intelligent composting system; Figure 5 This is a schematic diagram of the cross-section of the modular stack. Figure 6 This is a schematic diagram of the antibiotic resistance gene removal mechanism. Detailed Implementation

[0027] The specific embodiments and working principles of the present invention will be further described in detail below with reference to the accompanying drawings.

[0028] like Figure 1 As shown, a highly efficient composting method for cow manure organic fertilizer based on the high-altitude, cold, low-temperature, and oxygen-deficient environment of a plateau is described, with the following specific steps: Step 1, Raw material pretreatment: Mix the main fermentation material, fermentation auxiliary material, low-temperature compound microbial agent, and fermentation aid, and adjust the overall material moisture content and carbon-nitrogen ratio; First, mix the main fermentation ingredients and the auxiliary fermentation ingredients; In this embodiment, the main fermentation materials are fresh cow dung and straw powder, with the straw powder having a length of 2-3 cm; the fermentation auxiliary materials include rice bran, bone meal, and urea; the weight ratio of the fresh cow dung, straw powder, rice bran, bone meal, and urea is 70:25:3:1.5:0.5. Using the aforementioned main and auxiliary fermentation materials, not only is cow manure processed, but agricultural waste such as straw and rice bran are also utilized, with an overall conversion rate exceeding 99%. When the produced organic fertilizer is applied to degraded grasslands, the soil organic matter increases by 0.3%-0.5% annually.

[0029] Next, the mixed fermentation main material and fermentation auxiliary material are inoculated with a low-temperature compound microbial agent, and fermentation aids are added; The low-temperature compound microbial agent is: Lactobacillus plantarum was isolated from alpine meadow soil in Ganzi Prefecture; The optimal growth temperature for cold-resistant Bacillus subtilis is 15-25℃. Thermophilic Aspergillus niger remains active at 65°C.

[0030] The bacterial count ratio of *Lactobacillus plantarum*, *Bacillus subtilis* refractory, and *Aspergillus niger* was 0.5:1.0:0.8. The fermentation aid is a complex of sucrose isobutyrate acetate and dicosylamine. The weight ratio of the low-temperature compound microbial agent to the fermentation aid is 5:1, and the total weight ratio of the low-temperature compound microbial agent to the main fermentation material and the auxiliary fermentation material is 1:200.

[0031] See appendix Figure 2 The steps for obtaining the low-temperature compound microbial agent in this embodiment are as follows: Soil samples were taken from the alpine meadows; Microbial isolation and purification were performed on the sampled soil; The isolated and purified microorganisms were subjected to low-temperature acclimatization screening to obtain Lactobacillus plantarum, Bacillus subtilis refluxate, and Aspergillus niger thermophilus. The synergistic effect of the screened cold-resistant strains was verified to obtain the above three cold-resistant strains. The 16S rRNA gene sequencing of the three obtained cold-resistant strains verified that the three strains synergistically could generate 12.3 kJ / kg of metabolic heat at 5℃, with a specific growth rate of 0.08 h⁻¹. - 1. This means obtaining a low-temperature compound microbial agent that meets the requirements after formulation. Thus, by combining cold-resistant strains (Lactobacillus plantarum and Aspergillus niger) with fermentation aids, composting can be started quickly even when the ambient temperature is as low as 5°C, and the temperature can rise to above 55°C within 48 hours, solving the problem of "difficult start-up" for high-altitude composting.

[0032] During implementation, the low-temperature compound microbial agent is coated with microcarrier microspheres to facilitate better inoculation into the fermentation raw materials. The structure of the microcarrier microspheres is as follows: Figure 3 As shown, from the inside out, it includes: The PCM layer is made of a mixture of natural fatty acids or plant waxes, with a melting point of 8–10℃, a latent heat of 150–200kJ / kg, and a diameter ratio of 40–60% as indicated. The nutrient slow-release layer is made of modified cellulose and rice bran powder, with a thickness of 100–300 μm; The bacterial carrier layer has the low-temperature composite bacterial agent on its surface or contains the aforementioned low-temperature composite bacterial agent. The semi-permeable shell is composed of chitosan / alginic acid crosslinking and a SiO2 nanoporous coating with a pore size of 50–500 nm.

[0033] The diameter of the microcarrier microspheres ranges from 0.5 to 3 mm, preferably from 1 to 2 mm.

[0034] In this embodiment, the urea is used for initial C / N ratio fine-tuning, and the overall material moisture content is adjusted using glacial acetic acid diluted solution (25 times) to adjust the overall material moisture content to 55%-60%, and the initial C / N ratio is controlled at 25:1.

[0035] Step 2: Aerobic fermentation covered by nanomembrane: Step 2.1: Stack the mixed raw materials into a trapezoidal stack with a base length of 10-30m, a base width of 2-5m, and a height of 1-2m, and cover the surface with an NCS nanofilm. In this example, the NCS nanomembrane has a thickness of 0.15 mm, an air permeability of 1200 g / m²·24 h, and a temperature resistance of -20℃ to 80℃. The microporous structure of the nanomembrane achieves water resistance and air permeability, while effectively collecting odors.

[0036] In practice, the mixed raw materials are piled into modular stacks, the structure of which can be found in the appendix. Figure 5 Specifically: The pile is trapezoidal in shape: 4m wide at the base, 1.8m high, and 20m long. Nanofilm: A 0.15 mm thick NCS nanofilm is used as a cover layer, with a 10–50 mm air cavity between the film and the stack; a membrane tensioning mechanism consisting of automatic tensioning cables is used to tension and fix the NCS nanofilm. Under-membrane gas collection chamber: A gas collection pipeline with a diameter of Φ50–100mm is connected through the NCS nanomembrane. The gas collection pipeline uses DN50 stainless steel pipe and is equipped with a bypass valve and differential pressure gauge. Zoned airflow base plate: Modular spliced ​​plate made of HDPE or weathering steel plate, with a zone spacing of 2–5m. The total area of ​​the ventilation holes in each zone accounts for 3% of the total area, and the hole diameter is 10–25mm. Connecting flange DN80, controlled by solenoid valve.

[0037] PCM layer: Plate-like or granular layer, 20–50 mm thick;

[0038] Sensor locations: One node every 2.5m, with temperature probes (three in total, at depths of 0.2m, 0.6m, and the core), O2 / CO2 sensors, humidity probes, and small sampling ports placed within each node.

[0039] Step 2.2: Install a ventilation system at the bottom of the trapezoidal stack to construct an intelligent composting system; See appendix Figure 4 The intelligent composting system includes a raw material mixing system, an NCS nanofilm covering system, a dynamic turning machine, a ventilation system, and an intelligent control system. The raw material mixing system is used to mix the main fermentation material, fermentation auxiliary material, low-temperature compound microbial agent, and fermentation aid. The NCS nanofilm covering system is used to cover and wrap the trapezoidal stacks of mixed raw materials. The dynamic turning machine turns the trapezoidal stacks of materials. The ventilation system is used to introduce air into the NCS nanofilm covering system. The intelligent control system is used to control the raw material mixing system, the NCS nanofilm covering system, the dynamic turning machine, and the ventilation system. In specific implementation, the NCS nanofilm covering system uses a nanofilm with a thickness of 0.15 mm, an air permeability of 1200 g / m2·24h, and a temperature resistance of -20℃ to 80℃; the dynamic turning machine adopts a planetary gear system structure with a turning depth of 1.2 m; the intelligent control system is based on the BP neural network algorithm to establish a multi-parameter coupled control model of temperature (T)-oxygen (O2)-moisture (H2O).

[0040] Furthermore, the ventilation system includes a controller and a ventilation actuator. The input terminal group of the controller is connected to a temperature sensor for detecting the core temperature of the material, an oxygen sensor for detecting the oxygen content of the material, and a moisture sensor for detecting the moisture content of the material. The controller controls the ventilation actuator using a control model based on the detected core temperature, oxygen content, and moisture content of the material. The expression for the control model is: in, , These are the weighting coefficients. b For bias terms, , These represent the oxygen content and moisture content of the material in the trapezoidal stack, respectively.

[0041] Step 2.3: Fermentation is carried out, and dynamic turning is performed according to the predetermined turning strategy based on the core temperature of the pile, and ventilation is performed according to the predetermined ventilation strategy. In this example, the predetermined turning strategy is a temperature-triggered dynamic turning strategy, and the specific steps are as follows: When the fermentation temperature is between 5-25℃, turn the pile over once on the first day; When the fermentation temperature rises to 65-75℃ and remains stable above 65℃ for more than 48 hours, turn the pile over once every 2 days. When the fermentation temperature drops to 30-40℃, turn the pile over once every 7 days; When the fermentation temperature is raised to 65-75℃, a high-frequency turning method, such as turning the compost every two days, can significantly improve the germination index (GI) and effectively eliminate pathogenic bacteria such as Staphylococcus aureus and macrolide-lincosamide-streptomycin B (MLSB) antibiotic resistance genes (ARGs). For the mechanism of antibiotic resistance gene removal, please refer to the appendix. Figure 6 The turning frequency was designed based on temperature changes and ARGs removal kinetics, breaking through the traditional fixed-time turning mode. High-frequency turning (every 2 days) not only increases humus content (1.91%-7.45%), but also effectively breaks the horizontal gene transfer chain of ARGs.

[0042] The predetermined ventilation strategy is as follows: Start-up phase: When the fermentation temperature is between 5-25℃, the ventilation system should operate at a speed of 0.5~1.5m. 3 Continuous ventilation at a rate of / min·ton; High-temperature period: When the fermentation temperature rises to 65-75℃, the ventilation system should be adjusted to a pressure of 0.2~0.5m. 3 Intermittent ventilation was carried out at a rate of / min·ton, with a ventilation time of 5min and an interval of 10min. Cooling period: When the fermentation temperature drops to 30-40℃, the ventilation system stops, which means natural ventilation.

[0043] This embodiment combines molecular membrane covering with controlled ventilation to achieve integrated heat preservation, moisture retention, and deodorization during the composting process, making it adaptable to composting fermentation at different altitudes. Actual measurements show that the system can maintain a core temperature above 60℃ even in high-altitude winters (-10℃), shortening the fermentation cycle by 30%.

[0044] Step 3, Aging Treatment: Transfer the fermented material to an insulated aging box for aging treatment; In this example, the specific process of the aging treatment is as follows: Transfer the primary fermented material to an insulated aging box, pile it up to a height of 1.2m, and allow natural ventilation; The aging temperature was maintained at 30-40℃, and the pile was turned over once every 7 days for 3-4 weeks. The aging process is complete when the temperature of the pile drops below 30°C and the germination index is ≥85%.

[0045] Step 4, Quality Inspection and Packaging: The aged material is tested for maturity. If the test results are satisfactory, the material is crushed, granulated and coated to obtain organic fertilizer.

[0046] In this embodiment, the specific steps for quality inspection and packaging are as follows: Maturity test: The maturity of the aged material is tested. If it meets the standard, the next step is carried out; otherwise, secondary fermentation is carried out until it meets the standard. Crushing and granulation: The aged material is crushed through a 60-mesh sieve and then mixed with a viscous additive (acid-treated straw cellulose) at a mass ratio of 10:1. The mixture is then granulated into 2-4mm particles using a low-temperature granulator. Enhanced efficacy through coating: Fluidized bed equipment is used to coat the granules with a coating agent, with the coating rate controlled at 5%-8%. In specific implementation, trace elements such as Ca, Mg, and Zn can also be added to the coating agent to make the organic fertilizer contain trace elements such as Ca, Mg, and Zn, thereby enhancing the efficacy of the obtained organic fertilizer. Quality testing: The finished organic fertilizer is tested for total nutrients (N+P2O5+K2O≥5%), organic matter (≥45%), and heavy metal content to ensure compliance with national standards.

[0047] Application Example 1: Location of implementation: Nagqu Prefecture, Tibet, at an altitude of 4500m. Take 700 kg of fresh yak dung, mix it with 250 kg of barley straw fragments, 30 kg of rice bran, 15 kg of bone meal, and 5 kg of urea; Add 5 kg of low-temperature compound microbial agent (Lactobacillus plantarum: Bacillus subtilis: Aspergillus niger = 0.5:1.0:0.8) and 1 kg of fermentation aid; The moisture content was adjusted to 58% with glacial acetic acid dilution, and then covered with a nanofilm after stacking. Forced ventilation for 7 days, with the pile turned over once on the 3rd day, the core temperature reached a maximum of 68.2℃; Transferred to an aging warehouse for 20 days, during which time the pile was turned over 3 times; The final yield was approximately 800 kg of granular organic fertilizer, with a GI value of 89% and no detectable coliform bacteria, meeting the national standards for organic fertilizer.

[0048] The implementation benefits are compared as follows: Application Example 2: Location: Gannan Prefecture, Gansu Province, at an altitude of 3000m An intelligent composting system is used to process a mixture of cow manure and vegetable waste in a weight ratio of 7:3. Remotely monitor the reactor temperature via a mobile app and automatically adjust ventilation. The total fermentation cycle is 22 days, which is 40% shorter than the local traditional method; The fertilizer produced, when applied to the cultivation of highland summer vegetables (broccoli), increases yield by 12% and reduces the incidence of diseases and pests.

[0049] Application Example 3: The following example, using Huayi Livestock Breeding Co., Ltd. in Luhuo County, Ganzi Tibetan Autonomous Prefecture as a case study, illustrates the implementation of this invention: Implementation location: Luhuo County, Ganzi Tibetan Autonomous Prefecture; Processing capacity: 50 tons of yak dung per day; Process parameters: Raw material ratio: 70% yak dung + 25% highland barley straw + 3% rice bran + 0.5% microbial agent; Stack dimensions: 4m base width × 1.8m height × 20m length; Ventilation volume: 1.2 m³ / min·ton during startup, 0.4 m³ / min·ton during high-temperature period; Turning over the pile: once each on days 3, 5, and 7.

[0050] The measured data shows that: Start-up rate: At an ambient temperature of 0–10℃, the reactor core temperature reaches ≥55℃ within 48–72 hours; The highest temperature in the reactor core reached 68.5℃ and lasted for 12 days; The coliform count increased from 1.2 × 10⁻⁶. 6 CFU / g decreased to undetectable levels; The total nutrient content (N+P2O5+K2O) of the organic fertilizer reached 6.8%, exceeding the NY525-2021 standard; Field trials showed that the yield of barley increased by 120 kg per mu, and the soil bulk density decreased by 0.15 g / cm3.

[0051] This invention combines the advantages of low-temperature bacterial agents, intermittent dynamic aerobic composting, nanofilm covering, and fermentation technologies, solving problems such as low composting efficiency, nutrient loss, and environmental pollution in high-altitude environments.

[0052] The technical solution provided by this invention has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this invention. It should be noted that those skilled in the art can make several improvements and modifications to this invention without departing from the principles of this invention, and these improvements and modifications also fall within the protection scope of the claims of this invention.

Claims

1. A high-efficiency composting method for cow dung organic fertilizer based on high-altitude alpine low-temperature hypoxic environment, characterized by, The method comprises the following steps: Step 1, raw material pretreatment: mixing fermentation main materials, fermentation auxiliary materials, low-temperature composite microbial agents and fermentation auxiliary agents, and adjusting the water content and carbon-nitrogen ratio of the whole material; Step 2, nano-membrane covered aerobic fermentation: Step 2.1, building the mixed raw materials into a trapezoidal pile and covering the nano-membrane on the surface; Step 2.2, laying a ventilation system at the bottom of the trapezoidal pile; Step 2.3, fermentation, dynamic turning according to the predetermined turning strategy and ventilation according to the predetermined ventilation strategy according to the temperature of the pile core; Step 3, aging treatment: transferring the fermented material to an insulation aging box for aging treatment; Step 4, quality detection and packaging: detecting the composting degree of the aged material, and if the detection meets the standard, crushing, granulating and coating the material to obtain the organic fertilizer.

2. The efficient composting method of cow dung organic fertilizer based on highland alpine low temperature and hypoxic environment according to claim 1, characterized in that: The fermentation main materials are fresh cow dung and straw powder, the length of the straw powder is 2-3 cm, the fermentation auxiliary materials include rice bran, bone meal and urea, and the weight ratio of the fresh cow dung, straw powder, rice bran, bone meal and urea is 70:25:3:1.5:0.

5.

3. The efficient composting method of cow dung organic fertilizer based on highland alpine low temperature and hypoxic environment according to claim 1, characterized in that: The low-temperature composite microbial agent is composed of Lactobacillus plantarum, Bacillus subtilis and Aspergillus niger, and the ratio of the number of the three bacteria is 0.5:1.0:0.

8.

4. The efficient composting method of cow dung organic fertilizer based on highland alpine low temperature and hypoxic environment according to claim 3, characterized in that, The low-temperature composite microbial agent is obtained through the following process: Sampling the highland meadow soil; Microbial separation and purification of the sampled soil; Low-temperature domestication and screening of the separated and purified microorganisms, and verification of the synergistic effect to obtain cold-resistant strains; Gene sequencing of the obtained cold-resistant strains to obtain the low-temperature composite microbial agent.

5. The efficient composting method of cow dung organic fertilizer based on highland alpine low temperature and hypoxic environment according to claim 1, characterized in that: The fermentation auxiliary agent is sucrose ester of acetic acid and isobutyric acid and double coconut alkyl amine compound.

6. The efficient composting method of cow dung organic fertilizer based on highland alpine low temperature and hypoxic environment according to claim 1, characterized in that: The water content of the whole material in step 1 is 55%-60%, and the carbon-nitrogen ratio is 25:

1.

7. The efficient composting method of cow dung organic fertilizer based on highland alpine low temperature and hypoxic environment according to claim 1, characterized in that: The ventilation system comprises a controller and a ventilation execution mechanism, the input end of the controller is connected with a temperature sensor for detecting the temperature of the material pile core, an oxygen sensor for detecting the oxygen content of the material and a moisture sensor for detecting the water content of the material, and the controller controls the ventilation execution mechanism according to the detected temperature, oxygen content and water content of the material pile core by using a control model; The expression of the control model is: wherein, , is a weight coefficient, b is a bias term, , are the oxygen content and water content of the material in the trapezoidal pile, respectively.

8. The efficient composting method of cow dung organic fertilizer based on highland alpine low temperature and hypoxic environment according to claim 1, characterized in that: In step 2.3, the temperature of the pile core is controlled at 65-70 DEG C during the primary fermentation, and maintained for 7-10 days.

9. The efficient composting method of cow dung organic fertilizer based on highland alpine low temperature and hypoxic environment according to claim 1, characterized in that: In step 2.3, the predetermined turning strategy is: When the fermentation temperature is 5-25 DEG C, turn the pile once a day; When the fermentation temperature rises to 65-75 DEG C and is stable above 65 DEG C for more than 48 hours, turn the pile once every 2 days; When the fermentation temperature drops to 30-40 DEG C, turn the pile once every 7 days; The predetermined ventilation strategy is: When the fermentation temperature is at 5-25℃, continuously ventilate at the rate of 0.5-1.5 m 3 / min·ton;​ When the fermentation temperature is raised to 65-75℃, intermittent ventilation is carried out at a rate of 0.2-0.5 m 3 / min·ton, the ventilation time is 5 min, and the interval time is 10 min. When the fermentation temperature drops to 30-40 DEG C, do not ventilate.

10. The efficient composting method of cow dung organic fertilizer based on highland alpine low temperature and hypoxic environment according to claim 1, characterized in that: The specific process of the aging treatment is as follows: Transferring the material after the primary fermentation to an insulation aging box, the pile height is 1.2 m, and the ventilation is natural; The aging temperature is maintained at 30-40 DEG C, the pile is turned over once every 7 days, and the process lasts for 3-4 weeks; When the temperature of the pile body drops to below 30 DEG C and the germination index is greater than or equal to 85%, the aging treatment is completed.

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