Method for preparing ecological organic fertilizer from fruit and vegetable tailings and livestock and poultry manure in coordination

Abstract

The application discloses a method for preparing ecological organic fertilizer from fruit and vegetable tail vegetables and livestock and poultry manure, and the method comprises the following steps: S1, raw material pretreatment and proportioning; S2, layered packing and inoculation; S3, layered independent oxygenation; S4, layered turning and layer-by-layer discharging; S5, multi-parameter real-time monitoring and automatic control; S6, high-temperature aerobic fermentation: the mixed material sequentially experiences three stages of a temperature rising period, a high-temperature period and a temperature falling period in a multi-layer aerobic composting bin, and the aerobic fermentation is completed; S7, aging and post-processing: the compost product obtained in S6 is subjected to aging treatment, and the ecological organic fertilizer is obtained after detection. The agricultural organic wastes such as fruit and vegetable tail vegetables and livestock and poultry manure are converted into high-quality ecological organic fertilizer, the environmental pollution problem of agricultural wastes is solved, high-quality fertilizer sources are provided for agricultural production, and harmless treatment and resource utilization of the wastes are realized.

Description

Technical Field

[0001] This application belongs to the field of organic fertilizer preparation technology, specifically relating to a method for preparing ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure. Background Technology

[0002] With the continuous growth of vegetable planting area and the intensive development of animal husbandry, vegetable waste and livestock manure have become two major agricultural organic wastes. Statistics show that my country produces a large amount of vegetable waste (including discarded vegetable leaves, rotten fruit, vines, etc.) every year. If these wastes are randomly piled up in fields or along roadsides, they not only create a foul stench and breed mosquitoes, but the leachate produced during decomposition also pollutes the soil and groundwater, causing serious environmental pollution. At the same time, large-scale farms produce enormous amounts of livestock manure, which, if not properly treated, will also pollute the environment and threaten human health.

[0003] Vegetable and fruit waste is characterized by high water content (usually 80%–90%), rich organic matter, and easy spoilage, while livestock and poultry manure is characterized by relatively low organic matter content and high nitrogen content. Co-processing both to produce organic fertilizer can realize the resource utilization of waste and turn waste into treasure, which is an effective way to solve agricultural non-point source pollution.

[0004] Existing technologies include methods for composting fruit and vegetable waste with livestock and poultry manure to prepare organic fertilizer. For example, some methods involve chopping and dehydrating the waste, then mixing it with straw, livestock and poultry manure, and other materials for aerobic fermentation; others use windrow or trough composting methods. However, these existing technologies still have many shortcomings:

[0005] Firstly, traditional composting methods often involve single-layer static stacking or simple turning, resulting in uneven oxygen supply within the pile and the emergence of localized anaerobic zones. This leads to insufficient fermentation and uneven decomposition. Furthermore, turning the pile is labor-intensive and involves a harsh working environment.

[0006] Secondly, existing composting methods typically employ a uniform ventilation strategy, failing to provide precise oxygen supply based on the differentiated oxygen requirements at different stages of composting (heating period, high temperature period, cooling period), resulting in insufficient or excessive oxygen supply, which affects fermentation efficiency and product quality.

[0007] Third, traditional composting methods lack an effective heat cascade utilization structure, resulting in a large amount of heat loss during the composting process. Newly added materials require a long time to reach the appropriate fermentation temperature, leading to slow fermentation initiation and a long overall fermentation cycle.

[0008] Therefore, there is an urgent need for a method to prepare ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure, which can achieve tiered and precise oxygen supply, tiered utilization of heat, continuous production, and intelligent regulation capabilities. Summary of the Invention

[0009] This application provides a method for preparing ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure, aiming to solve the problems of uneven oxygen supply, long fermentation cycle and low heat utilization rate in the existing composting process.

[0010] A method for preparing ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure, the method comprising:

[0011] S1. Raw material pretreatment and proportioning: The fruit and vegetable waste is crushed, impurities removed, and dehydrated by squeezing, and the juice of the squeezed waste is collected for later use.

[0012] Crop straw is crushed; dehydrated vegetable waste, crushed straw and fresh livestock and poultry manure are mixed at a dry weight ratio, and the vegetable waste juice is added to adjust the total carbon-nitrogen ratio and initial moisture content of the mixture. After stirring evenly, the mixture is obtained.

[0013] S2, Layered Filling and Inoculation: The mixture obtained in S1 is layered and filled into the top layer of the multi-layer aerobic composting bin, with each layer having a predetermined thickness of material; during the material laying process, compound microbial agents are sprayed onto each layer of material;

[0014] S3, Layered Independent Aeration: Aeration pipes buried inside each layer of the pile body provide independent oxygen supply to each layer of the pile body;

[0015] Different ventilation parameters are set according to the different fermentation stages of each layer of the stack, and the ventilation of each layer is independently adjusted based on the real-time feedback signal of oxygen concentration in each layer.

[0016] S4. Layered turning and layer-by-layer feeding: During the composting fermentation process, the eccentric turning feeder at the bottom of each layer of aerobic composting bins is turned periodically, so that the material in the upper layer is evenly scattered into the next layer of aerobic composting bins under the action of gravity, realizing the layer-by-layer turning from top to bottom.

[0017] The material passes through each compartment from top to bottom and then falls to the bottom for discharge.

[0018] S5. Multi-parameter real-time monitoring and automatic control: Collect temperature, oxygen concentration and / or gas concentration data of each layer of the stack, compare and analyze the collected real-time data with preset thresholds, and automatically adjust the ventilation volume and / or turning frequency according to the comparison results.

[0019] S6. High-temperature aerobic fermentation: The mixed materials undergo three stages in sequence in the multi-layer aerobic composting chamber: heating period, high-temperature period and cooling period, to complete aerobic fermentation.

[0020] S7. Aging and Post-processing: The compost products obtained in S6 are aged and, after passing the test, ecological organic fertilizer is obtained.

[0021] Optionally, in step S1, the dehydrated vegetable waste, crushed straw, and fresh livestock and poultry manure are mixed at a dry weight ratio of (30-50):(20-40):(10-30); the amount of vegetable waste juice added is 5%-15% of the total mass of the mixture.

[0022] The total carbon-nitrogen ratio of the mixture is adjusted to 20:1 to 30:1, and the initial moisture content is adjusted to 55% to 65%.

[0023] Optionally, in S2, the multi-layer aerobic composting bin is a longitudinally stacked 4 to 6 independent bins, with the material fed from the top layer and moving downwards layer by layer;

[0024] The thickness of each layer of material is 0.8 to 1.2 m; the amount of the compound microbial agent added is 0.5% to 2.0% of the total mass of the mixture.

[0025] Optionally, in S3, the aeration pipe is located at 1 / 3 of the height of each layer of the pile, and a number of ventilation holes are opened on the circumference of the pipe, with the opening direction of the ventilation holes being obliquely downward.

[0026] The differentiated ventilation parameters are set according to the fermentation stage of each floor: the ventilation volume of the top floor during the heating period is not less than 478m³. 3 / h, the ventilation volume of the intermediate layer during the high-temperature period shall not be less than 683m³ / h. 3 / h, the ventilation volume of the ground floor during the cooling period should not be less than 194m³ / h. 3 / h.

[0027] Optionally, in S3, the method of independently adjusting the ventilation volume is: when the oxygen concentration of a certain layer is lower than a preset lower limit, the ventilation volume of that layer is increased;

[0028] When the oxygen concentration is higher than the preset upper limit, reduce the ventilation volume of that floor;

[0029] When the oxygen concentration is within the preset range, the current ventilation parameters remain unchanged;

[0030] Meanwhile, when the temperature of a certain layer of the stack exceeds the preset temperature threshold, the ventilation volume of that layer is increased to assist in heat dissipation, based on the oxygen concentration control.

[0031] Optionally, in S4, the eccentric flipper includes a flipping shaft and a flipping plate that flips around the flipping shaft, wherein the central axis of the flipping plate in the radial direction of the flipping shaft is offset from the axis of the flipping shaft;

[0032] An elastic grid is laid on the flap to support materials, and the grid flips synchronously with the flap.

[0033] Each flap is connected by a lever mechanism and driven by the same drive unit to achieve synchronous flipping.

[0034] Optionally, in step S4, the turning cycle is dynamically adjusted based on the feedback signals from the temperature sensor and the oxygen concentration sensor: when the pile temperature is higher than the first temperature threshold or the oxygen concentration is lower than the first oxygen threshold, the turning interval is shortened.

[0035] When the pile temperature is within the suitable fermentation temperature range and the oxygen concentration is within the suitable fermentation oxygen range, extend the turning interval.

[0036] Each time the material is turned over, the flip plate rotates to a predetermined angle, allowing the material to be evenly distributed to the next layer through the grid.

[0037] Optionally, in step S5, the real-time monitoring of multiple parameters includes: collecting temperature data at different locations along the height of each layer of the stack, oxygen concentration data at the center height of the stack, and ammonia and / or hydrogen sulfide concentration data.

[0038] When the ammonia concentration exceeds the first ammonia threshold or the hydrogen sulfide concentration exceeds the first hydrogen sulfide threshold, the deodorization device will be automatically activated and the ventilation volume will be reduced.

[0039] Optionally, in S6, the heating period is from day 0 to day 2, during which the pile temperature rises to above 55°C;

[0040] The high-temperature period is from day 2 to day 9, and the temperature of the pile body is maintained above 60°C for 5 to 7 days.

[0041] The cooling period is from day 9 to day 12, during which the temperature of the pile gradually decreases to 35 to 40°C; the entire fermentation cycle is 7 to 12 days.

[0042] Optionally, in step S7, the aging process takes 7 to 14 days;

[0043] After aging, the seed germination index of the compost products is tested. When the seed germination index is greater than 80%, the compost is considered to be fully decomposed.

[0044] The decomposed compost products are screened and crushed to obtain ecological organic fertilizer.

[0045] Compared with the prior art, this application has at least the following beneficial effects:

[0046] This application involves layering the mixed materials into multi-layer aerobic composting chambers. Each layer is independently equipped with aeration pipes and sensor groups. Different ventilation parameters are set according to the different fermentation stages of each layer (heating period, high-temperature period, cooling period). Based on the real-time feedback signals from the oxygen concentration sensors in each layer, the opening degree of the solenoid valves and the ventilation frequency of each layer are independently adjusted by a PLC control system. This layered, independent, and precise oxygen supply method ensures that each layer of the compost is always in a suitable aerobic fermentation state, avoiding the uneven oxygen supply problem caused by traditional uniform ventilation methods, and effectively improving the degradation efficiency of organic matter and the uniformity of compost product quality.

[0047] This application employs a process architecture where materials move layer by layer from top to bottom, with each layer fermenting independently. The high-temperature gas generated by fermentation in the lower layer naturally rises to the upper layer, providing initial heat for newly added materials. Simultaneously, the heat generated by fermentation in each layer is transferred upwards in a step-by-step manner, forming a heat cascade recycling effect similar to a "steamer." This structure significantly improves the mass and heat transfer efficiency of the entire composting machine, effectively shortening the fermentation start-up time. Newly added materials can reach temperatures above 55°C within two days, achieving energy conservation and emission reduction.

[0048] This application utilizes an eccentric rotating feeder to periodically rotate the material, allowing the upper layer to be evenly distributed into the next aerobic composting bin under gravity, achieving top-down layer-by-layer material turning. After each turning, the upper bin is emptied, allowing for the continuous feeding of new mixed materials. The material passes through each bin sequentially from top to bottom, experiencing three fermentation stages: heating, high temperature, and cooling. The entire fermentation cycle takes only 7–12 days, far superior to the 25–40 days typically required by traditional composting methods.

[0049] This application installs a multi-parameter sensor group, including temperature sensors, oxygen sensors, and a five-in-one gas detector (capable of simultaneously monitoring five gases: oxygen, carbon dioxide, methane, ammonia, and hydrogen sulfide), in each aerobic composting chamber. A PLC control system collects real-time data once per second and automatically adjusts ventilation and turning frequency according to preset control strategies. The control system also features remote monitoring capabilities, allowing authorized users to view the operational status and receive alarms in real time via computer or mobile device. This intelligent control method ensures that the composting process remains within the optimal process parameter range, guaranteeing the stability and consistency of product quality.

[0050] The compost produced by the method described in this application has a seed germination index (GI) of over 80% (experimental data show a maximum of 91.2%), indicating that the compost is fully decomposed and non-toxic to plants. All indicators, including organic matter content, total nutrient content, moisture content, pH value, fecal coliform count, and ascarid egg mortality rate, meet the requirements of the NY / T 525-2021 "Organic Fertilizer" standard. This application transforms agricultural organic waste such as fruit and vegetable waste and livestock manure into high-quality ecological organic fertilizer, solving the environmental pollution problem of agricultural waste while providing a high-quality fertilizer source for agricultural production, achieving the harmless treatment and resource utilization of waste. Attached Figure Description

[0051] Figure 1 This is a flowchart illustrating a method for preparing ecological organic fertilizer using fruit and vegetable waste and livestock and poultry manure, as provided in one embodiment of this application. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments.

[0053] This application provides a method for preparing ecological organic fertilizer using fruit and vegetable waste and livestock and poultry manure, such as... Figure 1 As shown, it includes the following steps:

[0054] S1. Raw material pretreatment and proportioning, the specific steps are as follows:

[0055] S1.1 The collected fruit and vegetable waste (including waste vegetable leaves, rotten fruit, vines, etc.) is transported to a hammer mill for crushing, and the crushed particle size is controlled between 0.1 and 2.0 cm. The crushed material is screened by a vibrating screen and then passed through a magnetic separator and an air separator to remove impurities such as plastic ropes, films, ironware, stones, and sand.

[0056] After impurities are removed, the waste vegetable material is fed into a screw press dewatering machine for pressing and dehydration. The screw press adopts a variable diameter screw design and is equipped with a 0.3-1.0 mm mesh screen. Through gradual pressure increase, the moisture content of the waste vegetable material is reduced from the initial 80%-90% to 50%-65%. The juice extracted from the waste vegetable material is collected through a filter screen and then transported to a sealed storage tank for temporary storage. This waste vegetable material is rich in soluble organic carbon and nutrients such as nitrogen, phosphorus, and potassium, and can be used as a moisture regulator and nutrient supplement in the subsequent composting process.

[0057] (1.2) The crop straw (selected from at least one of rice straw, corn straw or wheat straw) is fed into a straw crusher and crushed to a particle size of less than 5 cm;

[0058] (1.3) Fresh livestock and poultry manure (selected from at least one of pig manure, cow manure or chicken manure) is mixed with the dehydrated vegetable waste obtained in step (1.1) and the crushed straw obtained in step (1.2) at a dry weight ratio of (30-50):(20-40):(10-30) to adjust the total carbon-nitrogen ratio (C / N) of the mixture to 20:1-30:1 and the initial moisture content to 55%-65%;

[0059] At the same time, add 5% to 15% of the total mass of the mixture of vegetables and the collected vegetable juice in step (1.1) to supplement soluble organic carbon and trace elements. The amount of vegetable juice added can be dynamically adjusted according to the measured moisture content of the mixture. When the moisture content of the material is low, the amount of juice added should be increased appropriately, and vice versa, to ensure that the moisture content of the mixture is always maintained within the appropriate range of 55% to 65%.

[0060] Add each raw material into the mixer according to the above proportions and stir thoroughly. The stirring time is controlled at 5 to 10 minutes until the material has a uniform color and no visible lumps.

[0061] S2. Layered filling and inoculation, the specific steps are as follows:

[0062] The mixture obtained in step (1.3) is conveyed to the top feed inlet of the multi-layer aerobic composting silo via a bucket elevator. The bucket elevator adopts a Z-shaped tipping bucket structure, with the conveying height matching the total height of the composting silo, a lifting speed of 0.5–1.0 m / s, and a single lifting capacity controlled between 0.5 and 1.0 t. After entering the top feed inlet, the material is evenly spread on the grid of the uniform tipping system by the material distribution system;

[0063] The material distribution system employs a screw-driven uniform material distributor, comprising a gantry, unloader, conveyor belt, translation drive, track, guide trough, rotary screw, and screw drive. A long discharge port is located at the bottom of the guide trough. After the material is unloaded into the guide trough by the unloader, it is horizontally propelled to the discharge port by the rotary screw installed within the guide trough, and then evenly falls into the fermentation chamber below. During the distribution process, the translation drive drives the distribution mechanism to reciprocate along the length of the chamber, covering the entire length of the chamber to ensure a uniform and even distribution of material within the chamber. The thickness of a single layer is controlled between 0.8 and 1.2 meters. The amount of material per layer is determined based on the effective volume of the chamber and the loading coefficient, with each layer containing approximately 20 to 26 tons (based on a material bulk density of 550 kg / m³). 3 count);

[0064] During the spreading process, a compound microbial agent is evenly sprayed at 0.5% to 2.0% of the total mass of the mixture. The compound microbial agent is a liquid agent with an effective viable count of not less than 1.0 × 10⁻⁶ bacteria. 8 CFU / mL, containing Bacillus subtilis, Bacillus licheniformis, cellulolytic bacteria (Trichodermaviride or Cellulomonas) and yeast (Saccharomyces cerevisiae), each in a volume ratio of (2-3):(2-3):(1-2):(1-2);

[0065] The microbial agent is sprayed using an atomizing nozzle with a spray pressure of 0.3–0.6 MPa and a droplet size of 50–150 μm. The spray flow rate is automatically adjusted according to the material laying speed. The microbial agent is sprayed once after each layer of material is laid to ensure uniform distribution within the pile. The spraying amount for each layer can be fine-tuned according to the actual temperature of the material in that layer: during the heating period (top layer), the amount of microbial agent is appropriately increased to the upper limit of the ratio; during the high-temperature period (middle layer), the medium amount is maintained; and during the cooling period (bottom layer), it is appropriately reduced to the lower limit of the ratio.

[0066] The aerobic composting silos are fully enclosed box-type structures, stacked longitudinally in 4 to 6 layers. Each layer of aerobic composting silos is an independent rectangular chamber with single-layer external dimensions of 8990mm × 2650mm × (1100~2000)mm. The top chamber has a height of 1500mm (also serving as a feeding silo), the middle chambers have a height of 1100mm, and the bottom chamber has a height of 2000mm (also serving as a discharging silo).

[0067] The compost bin frame is welded from 5mm thick, 60mm x 60mm carbon steel square tubing, with the inner wall in contact with materials made of 304 stainless steel with a thickness of ≥1.2mm. The outside of the bin is covered with a 50mm thick polyurethane foam insulation layer to reduce heat loss during composting. Adjacent bins are connected by flanges and fitted with heat-resistant silicone rubber sealing strips to ensure airtightness between bins and prevent odor leakage.

[0068] Each layer of aerobic composting bins is independently equipped with aeration pipes and sensor groups: temperature sensors are arranged at 1 / 3 and 2 / 3 of the height of the compost pile to monitor temperature changes at different heights; oxygen sensors are arranged at the center of the compost pile to monitor the oxygen concentration inside the pile in real time; all sensors are heat-resistant, waterproof, and corrosion-resistant, with the temperature sensor detection range of -20 to 100℃ and accuracy ≤ ±1℃, and the oxygen sensor detection range of 0 to 25% and accuracy ≤ ±3%F·S;

[0069] The sensor is connected to the PLC control system via a data cable, collecting data once per second and transmitting it in real time. The top compartment has a sealed feed inlet cover, and the bottom compartment has a discharge outlet and unloading valve.

[0070] S3. Layered independent oxygenation and aeration: The oxygenation and aeration system is activated, and each layer of the pile is independently supplied with oxygen through stainless steel aeration pipes buried in the middle of each layer of the pile. The oxygenation and aeration system includes an aeration fan, a main air supply pipe, layered air supply branch pipes, and aeration pipes buried inside each layer of the pile.

[0071] The aeration blower is a variable frequency speed-regulating centrifugal blower with a rated air pressure of not less than 5000Pa. The blower speed is adjusted by a frequency converter to achieve stepless adjustment of the air supply. The main air supply pipe is a DN150 stainless steel pipe, arranged longitudinally along one side of the compost bin. Each layer of aerobic compost bins has a DN80 branch air supply pipe leading from the main air supply pipe. The branch pipe is equipped with a solenoid valve and a gas flow meter for independent control of the air supply and instantaneous flow monitoring for that layer. The aeration pipes buried inside each layer of the composting body are made of 316 stainless steel, which has good corrosion resistance. The aeration pipes have a ring or comb-shaped air distribution structure and are arranged above the grid of the uniform turning system, at 1 / 3 of the height of the composting body (i.e., the middle position of the composting body). The pipe diameter is 50-80mm, and the spacing between adjacent pipes is 300-500mm.

[0072] The aeration pipes have several ventilation holes on their circumference. These holes are divided into multiple groups, with equal distances between adjacent groups. The openings of the ventilation holes are angled downwards to prevent material from clogging them. The pipe opening ratio is 15%–25%, and the ventilation hole diameter is 3–8 mm. The aeration pipes in each layer are connected by flanges, and each layer of pipes has a drain outlet at the end for periodically draining condensate that accumulates in the pipes.

[0073] Different ventilation parameters were set according to the different fermentation stages of each layer of the stack. The determination of the ventilation volume took into account both the oxygen demand for microbial activity and the oxygen demand for material dehydration.

[0074] The specific calculation basis is as follows:

[0075] The top aerobic composting silo is in the heating phase, with microbial activity gradually increasing and the oxygen consumption rate continuously rising. Based on previous experiments, the maximum oxygen consumption rate during the heating period is 93 L / (m³). 3 •min) and effective volume of the silo (approximately 26m³) 3 ), from the formula The theoretical oxygen demand is calculated to be approximately 478.26 m³. 3 / h;

[0076] The intermediate aerobic composting chamber is in a high-temperature stage, where organic matter degrades in large quantities, and microbial metabolism is at its most vigorous, with a maximum oxygen consumption rate of 132.8 L / (m³). 3 The theoretical oxygen demand is approximately 682.92 m³ / min. 3 / h;

[0077] The bottom aerobic composting bin is in the cooling phase, and the easily degradable organic matter has been largely consumed, with the oxygen consumption rate dropping to 34.9 L / (m³). 3 The theoretical oxygen demand is approximately 179.46 m³ / min. 3 / h;

[0078] Considering the material dehydration requirements, with a daily processing capacity of 10 tons and an initial moisture content of 60% to an output moisture content of 40%, the total air volume required for material dehydration during a 12-day composting cycle is calculated to be approximately 55,900 m³. 3 This translates to an average ventilation volume of approximately 194.10 m³ per floor. 3 / h;

[0079] Taking into account both the oxygen demand for organic matter degradation and the oxygen demand for material dehydration, the maximum value between the two is taken as the lower limit for the design ventilation volume of each layer, that is: the ventilation volume of the top composting bin (heating period) shall not be less than 478m³. 3 / h; Ventilation volume of the intermediate composting bin (high-temperature period) shall not be less than 683m³ / h. 3 / h; the ventilation volume of the bottom compost bin (during the cooling period) should not be less than 194m³ / h.3 / h;

[0080] In actual operation, the frequency converter can be used to make fine adjustments within ±30% of the set value based on the real-time temperature, oxygen concentration and material moisture content monitoring data of each layer of the stack.

[0081] Each layer of aeration pipeline is equipped with a solenoid valve on its air supply branch. The PLC control system adjusts the opening degree and ventilation frequency of the solenoid valves on each layer according to the real-time feedback signal from the oxygen concentration sensor on each layer (the oxygen concentration is set to 8% to 15%), so as to achieve independent quantitative and precise aeration on a single layer.

[0082] The specific control logic is as follows: the oxygen concentration sensor on each floor collects data once per second and transmits it to the PLC control system; the PLC compares the measured oxygen concentration with the preset threshold (lower limit 8%, upper limit 15%).

[0083] When the oxygen concentration in a certain layer is below 8%, the system determines that the oxygen supply to that layer is insufficient, automatically increases the opening of the solenoid valve in that layer and increases the speed of the variable frequency fan to increase the ventilation volume;

[0084] When the oxygen concentration is higher than 15%, the system determines that there is an excess of oxygen and automatically reduces the opening of the solenoid valve and the fan speed to reduce the ventilation volume.

[0085] When the oxygen concentration is between 8% and 15%, the system maintains the current ventilation parameters unchanged;

[0086] Meanwhile, temperature sensor data is used as an auxiliary control parameter for regulation: when the temperature of a certain layer of the stack exceeds 70°C, the system automatically increases the ventilation volume of that layer to assist in heat dissipation based on oxygen concentration control.

[0087] When the reactor core temperature is below 50°C for more than 12 hours, the system should appropriately reduce the ventilation volume to minimize heat loss and promote reactor core heating. The solenoid valves on each layer should be opened in a time-sharing, rotating manner to avoid a sudden increase in fan load due to simultaneous high air consumption across multiple layers.

[0088] When a certain layer is in the process of turning and discharging material (about 5 to 10 minutes), the solenoid valve of that layer will automatically close to prevent a large amount of air from escaping through the discharge port. The air supply will be restored after the turning and discharging is completed and the silo door is closed.

[0089] All control parameters (real-time ventilation volume on each floor, solenoid valve opening, oxygen concentration, temperature, etc.) are recorded and stored through the PLC system, supporting historical data query and trend analysis;

[0090] S4. Layered turning and sequential feeding: An eccentric turning feeder is installed at the bottom of each aerobic compost bin, with two sets of uniform turning devices per layer, totaling 12 turning plates. The eccentric turning feeder includes a turning shaft and turning plates that rotate around the shaft. The turning plates are positioned above the shaft, with their radial axis offset from the shaft's center, creating an eccentric arrangement. The turning plates have a long side ≥400mm, a short side ≥300mm, and a total width ≥700mm. The shaft diameter is 60mm, made of 45# steel, and its allowable torque, after torsional strength testing, is 1271.7 N·m, meeting the actual working condition requirement of ≥1166.65 N·m of eccentric torque.

[0091] The bottom of the flap is equipped with multiple spaced reinforcing ribs to improve its strength and prevent deformation during long-term load-bearing and repeated flipping. An elastic grating, made of 316 stainless steel wire with mesh sizes of 20mm×20mm~30mm×30mm, is laid on the flap to support materials. The grating is fixed to the upper surface of the flap and flips synchronously with it. While supporting materials, the elastic grating also provides ventilation, facilitating gas flow within the stack and preventing material leakage from the flap gaps when it is not in motion. All flaps are connected by a tie-rod mechanism and driven by the same drive unit to achieve synchronous flipping.

[0092] During the composting process, a cylinder drives a lever mechanism to cause the eccentric turning feeder to perform a periodic reciprocating turning motion.

[0093] The cylinder is an SC160×700 type cylinder with a standard stroke of 700mm and a pressure bearing capacity of 0.1~2.0MPa. There are two cylinders, which are respectively set on both sides of the silo body. One end of the cylinder is hinged to one end of the flap through the second hinge shaft, and the other end is hinged to the side wall of the composting silo through the hinge block.

[0094] The cylinder is connected to an air compressor, which converts the pressure energy of compressed air into mechanical energy, driving the tie rod mechanism to rotate the eccentric tilting feeder around the tilting plate shaft. The tilting cycle is dynamically adjusted by the PLC control system based on feedback signals from temperature and oxygen sensors. The specific control logic is as follows: The PLC system collects temperature data at 1 / 3 and 2 / 3 of each layer of the stack and oxygen concentration data at the center height of the stack in real time.

[0095] When the temperature of the pile exceeds 70°C or the oxygen concentration is below 6%, it indicates that the pile is in an overheated state or the oxygen supply is seriously insufficient. The system automatically shortens the turning interval to 12-24 hours and accelerates heat dissipation and oxygen replenishment by increasing the turning frequency.

[0096] When the temperature of the pile is stable at 55-65℃ and the oxygen concentration is 8%-12%, it indicates that the pile is in a suitable aerobic fermentation state. The system extends the turning interval to 48-72 hours to reduce the disturbance of the microbial community and reduce energy consumption.

[0097] Each time the material is turned over, the cylinder drives the flap to rotate around the axis at an angle of 90° to 135°. The flap rotates from the horizontal material receiving position to the inclined material unloading position, and then returns to its original position in the opposite direction. A single turning action takes 5 to 10 minutes. During the turning process, the solenoid valve of the oxygenation and aeration pipe of this layer is automatically closed to prevent a large amount of air from escaping from the discharge port. After the turning is completed and the flap is reset, the air supply is restored.

[0098] When the eccentric tilting feeder tilts, the upper layer of material is evenly scattered into the next layer of aerobic composting bins under the action of gravity through the grid, realizing the layer-by-layer turning of material from top to bottom;

[0099] Because the flap is eccentrically set, the horizontal distance between the two sides of the flap and the axis of the flap shaft is not equal (L1:L2 is greater than 1 or less than 1). When the flap is flipped, the material can make full use of its own gravity to fall, the unloading is smoother, the driving energy consumption is effectively reduced, and the material jamming problem that is easy to occur in conventional symmetrical flipping devices is avoided.

[0100] After each material turning is completed, the upper chamber is emptied and new mixed materials can be continuously fed in through the top feed port to achieve continuous feeding operation. The material passes through each chamber from top to bottom, going through the three fermentation stages of heating, high temperature and cooling, and finally falls to the bottom discharge system to be moved to the aging area.

[0101] During the unloading process of the flip plate, the high-temperature gas generated by the fermentation in the lower layer naturally rises to the upper layer, providing heat for the newly added material in the upper layer and promoting the rapid heating of the material in the upper layer.

[0102] Meanwhile, the heat generated by fermentation in each layer is transferred from bottom to top, forming a heat cascade recycling effect similar to a "steamer". This heat cascade utilization structure significantly improves the mass and heat transfer efficiency of the entire composting machine, effectively shortens the fermentation start-up time, and achieves energy saving and consumption reduction;

[0103] S5. Real-time monitoring and automatic control of multiple parameters: A sensor group is installed in each layer of aerobic composting bins. The sensor group includes a temperature sensor, a humidity sensor, a pressure sensor, a pH sensor, and a five-in-one gas detector.

[0104] Among them, the temperature sensor adopts a platinum resistance temperature sensor (Pt100 type), with a detection range of -20~100℃, a measurement accuracy of ≤±1℃, and a response time of <1s. It is arranged at 1 / 3 and 2 / 3 of the height of each layer of the stack, with a total of 2 temperature measuring points in each layer to monitor the temperature distribution at different heights of the stack.

[0105] The humidity sensor adopts the capacitive dielectric constant method humidity sensor, with a detection range of 0-99%, a measurement accuracy of ≤±2%, and a response time of <1s. Its sensitive element has been optimized for dust and corrosion resistance, making it suitable for high dust and high water vapor conditions.

[0106] The pressure sensor is a diffused silicon piezoresistive pressure sensor with a detection range of -0.1 to 60 MPa and an accuracy class of 0.5. It is installed on the side wall of each chamber to monitor changes in air pressure inside the chamber. The pH sensor has a polyetherimide housing and a pointed electrode structure, with a detection range of 3 to 9, a measurement accuracy of ±0.3, and a response time of <15s.

[0107] The five-in-one gas detector has a built-in electrochemical gas sensor array that can simultaneously monitor the volume concentration of five gases: oxygen (O2), carbon dioxide (CO2), methane (CH4), ammonia (NH3), and hydrogen sulfide (H2S). The oxygen sensor has a detection range of 0–25% and a resolution of 0.1%; the carbon dioxide sensor has a detection range of 0–20% and a resolution of 0.1%; the methane sensor has a detection range of 0–100% and a resolution of 0.1%; the ammonia sensor has a detection range of 0–1000 ppm and a resolution of 1 ppm; and the hydrogen sulfide sensor has a detection range of 0–2 ppm and a resolution of 0.01 ppm. The measurement accuracy of all five gases is ≤ ±3% F·S, and the response time is < 1 s.

[0108] The signal output of each of the above sensors is a 4-20mA analog current signal or an RS485 digital signal, which is connected to the analog input module or serial communication module of the PLC control system through a shielded cable. Each sensor probe is waterproof, dustproof, and corrosion-resistant. The temperature sensor probe is fitted with a 316 stainless steel sheath, and the humidity sensor and pH sensor probes are equipped with a porous protective cover to prevent material blockage.

[0109] All sensors collect data once per second. After being amplified, filtered, and converted from analog to digital by the signal conditioning module, the data is transmitted in real time to the central processing unit of the PLC control system.

[0110] The PLC control system uses a Siemens S7-1200 or equivalent programmable logic controller, configured with an analog input module (8 channels, 12-bit resolution), a digital input / output module (16 channels), and an RS485 communication module. The control system compares and analyzes the collected real-time data with preset thresholds and automatically outputs execution instructions according to the following control strategy:

[0111] Temperature control: When the temperature at 1 / 3 or 2 / 3 of the pile is below 50℃ and lasts for more than 24 hours, it indicates that the pile temperature is insufficient and the microbial activity is low. The system will automatically increase the opening of the solenoid valve at that level to increase the ventilation volume (the increase is 20% to 30% of the set value) and shorten the turning interval to 12 to 24 hours to activate the metabolic activity of microorganisms.

[0112] When the pile temperature exceeds 75°C, the system automatically reduces the opening of the solenoid valve in that layer to reduce the ventilation volume (the reduction is 15% to 25% of the set value) and increases the turning frequency (the turning interval is shortened to 12 to 24 hours). The turning process dissipates heat and prevents excessive high temperature from damaging the microorganisms. When the pile temperature is in the suitable fermentation range of 55 to 65°C, the system maintains the current ventilation and turning parameters unchanged.

[0113] Oxygen concentration control: When the oxygen concentration of a certain layer remains below 6% for more than 6 hours, the system will issue an oxygen deficiency alarm (an audible and visual alarm signal will be pushed to the remote monitoring terminal at the same time), and forcibly open the aeration solenoid valve of that layer to the fully open state. At the same time, the variable frequency fan speed will be increased to more than 90% of the rated speed until the oxygen concentration rises back to more than 8%.

[0114] When the oxygen concentration is within the normal range of 8% to 15%, the system maintains normal oxygen supply according to the differentiated ventilation parameters set in S3; when the oxygen concentration is higher than 15%, the system automatically reduces the opening of the solenoid valve to reduce excess oxygen supply.

[0115] Odor control: When the concentration of ammonia (NH3) exceeds 100 ppm or the concentration of hydrogen sulfide (H2S) exceeds 2 ppm, the system automatically activates the deodorization device. The deodorization device, which is a biological filter or chemical scrubbing tower, is installed on the exhaust main of the composting silo. After the deodorization device is activated, the system simultaneously and automatically reduces the ventilation volume of that floor (by 10% to 20% of the set value) to reduce odor generation and emissions.

[0116] Pressure safety control: When the pressure inside a certain layer exceeds 0.05MPa, the system automatically opens the pressure relief valve for that layer to relieve pressure; when the pressure exceeds 0.1MPa, the system issues a high-pressure alarm and forcibly stops the air supply to that layer.

[0117] The control system is equipped with a field touchscreen, allowing operators to set parameters, switch between manual and automatic modes, control equipment start / stop, and view real-time data. The control system has a built-in data storage module that automatically records operating parameters for each layer of the stack, such as temperature, humidity, pressure, pH, concentrations of five gases, ventilation volume, and number of material turnings, in Excel or CSV format. Data is retained for at least 180 days and supports historical data query, trend curve plotting, and report export. The control system connects to the field LAN via an industrial Ethernet interface and is connected to a remote server via a VPN encrypted channel.

[0118] Within the domestic internet coverage area, authorized users can view the composting operation status, real-time data from each sensor layer, historical data curves, and alarm information in real time through a computer web browser or a mobile APP (supporting Android and iOS systems), and receive abnormal alarm notifications pushed by the system (including SMS push and APP push).

[0119] The control system also has a manual control backup system. When the PLC automatic control system fails, the operator can manually control the start and stop of each layer of fans, solenoid valves and cylinders through the buttons and knobs on the field control cabinet to ensure that the composting operation is not interrupted.

[0120] S6. High-temperature aerobic fermentation: The mixed materials undergo three stages in sequence within the multi-layer aerobic composting chamber: a heating period, a high-temperature period, and a cooling period. The temperature changes in each stage are closely related to the metabolic activity of microorganisms, as detailed below:

[0121] Heating period (days 0-2): After the new material enters the top aerobic composting bin, under the heat gradient circulation effect of the "steamer effect" described in S4, the rising hot airflow at the bottom provides initial heat to the top material. At the same time, the control system described in S5 automatically increases the ventilation volume and shortens the turning interval to 12-24 hours when it detects that the pile temperature is below 50°C, further activating the metabolic activity of microorganisms.

[0122] Under the combined effect of the above multiple factors, the temperature of the compost pile rose rapidly, reaching over 55°C at both one-third and two-thirds of the pile within two days. In actual operation, if the ambient temperature is low in autumn and winter, resulting in insufficient heating rate, heat loss can be reduced by supplementing the external insulation layer of the compost bin (50mm thick polyurethane foam) or by reducing ventilation, ensuring that the compost pile reaches over 55°C within two days.

[0123] High-temperature period (days 2-9): The pile temperature is maintained above 60℃ for 5-7 days. This stage is the critical period for the large-scale degradation of organic matter, decomposition of lignocellulose, and elimination of pathogens.

[0124] Thermophilic microorganisms (Bacillus, Actinomycetes, etc.) become the dominant bacterial group, organic matter is rapidly decomposed, and recalcitrant components such as cellulose and hemicellulose are degraded in large quantities;

[0125] During this period, temperature sensors continuously monitor the temperature at 1 / 3 and 2 / 3 of the pile body once per second, and the control system compares the temperature difference between the two measuring points in real time to ensure that the temperature uniformity difference does not exceed 5°C.

[0126] When the temperature difference exceeds 5℃, the system automatically increases the turning frequency of that layer (shortening the turning interval to 12-24 hours) to improve the mixing uniformity of materials inside and outside the compost pile. When the pile temperature exceeds 70℃, the system automatically reduces the ventilation volume and increases the turning frequency according to the control strategy described in S5 to prevent excessive high temperature from damaging microorganisms. Temperatures above 60℃ for 5-7 consecutive days during the high-temperature period can effectively kill pathogens, insect eggs, and weed seeds in the compost material, meeting the sanitary requirements for harmless treatment of feces.

[0127] Cooling period (days 9-12): As easily degradable organic matter is gradually depleted, microbial metabolic activity weakens, and the compost pile temperature gradually decreases from above 60℃ to 35-40℃. During this stage, based on feedback signals from the oxygen concentration sensor, the control system ensures that the ventilation rate of the bottom compost bins is no less than 194 m³ / h, as set in S3. 3 The oxygen supply is maintained at a constant rate of / h, while the turning interval is extended to 48–72 hours. During the cooling period, the temperature changes at 1 / 3 and 2 / 3 of the pile body need to be continuously monitored to ensure uniform cooling and avoid uneven ripening in local areas due to excessively rapid cooling.

[0128] The entire fermentation cycle is 7 to 12 days. After the material is fed from the top layer, it is dropped from top to bottom layer by layer in the manner described in S4 (4.3), passing through each layer of aerobic compost bins and experiencing three stages: heating period, high temperature period and cooling period.

[0129] After the material falls into the bottom aerobic composting bin and completes the cooling fermentation period, it is moved to the aging area via the bottom discharge system for the aging treatment described in S7. After the fermentation cycle is completed, the seed germination index (GI) of the compost product is sampled and tested according to the method described in S7 (7.2). When the GI is greater than 80%, the compost is considered to be fully decomposed.

[0130] S7. Aging and Post-processing: The compost products obtained in S6 are transferred to the aging area via a bottom discharge system. The aging area should preferably have a hardened concrete floor and be equipped with a rain shelter. The floor should have a drainage slope (sloping towards the collection ditch, with a slope of 2‰ to 3‰) to prevent rainwater from seeping into the material and causing secondary fermentation or nutrient loss. The material is stacked in the aging area in the form of windrows, with a base width of 3.0 to 5.0 m, a height of 1.5 to 2.0 m, and a trapezoidal cross-section.

[0131] Aging should be carried out under natural ventilation for 7–14 days, with the pile turned over every 7 days. Turning can be done using a self-propelled or tracked turner. It is important to ensure that the turning is uniform and thorough, and that the bottom and edge materials are fully turned over to the upper part of the pile to avoid dead corners or areas of insufficient degradation.

[0132] Turning the pile should be done in sunny weather. If the moisture content of the material is low (below 25%) after turning, water can be sprayed appropriately to maintain a suitable moisture environment for the post-ripening activity of microorganisms. During the aging period, the pile temperature should be gradually reduced to close to the ambient temperature (35-40℃). When the material is uniformly brown, has no foul odor, and has a loose, granular structure, it indicates that the aging is basically complete.

[0133] After aging, samples were taken to test the seed germination index (GI). Samples were collected from different heights and depths of the stack using a multi-point sampling method (no fewer than 5 sampling points), and thoroughly mixed before being used as the test samples.

[0134] Accurately weigh 10.0 g (accurate to 0.01 g) of compost product and place it in a 250 mL Erlenmeyer flask. Add 100 mL of ultrapure water (resistivity ≥ 18.2 MΩ·cm), cap the flask, and place it in a reciprocating shaker. Shake at 135 Hz for 4 hours. After shaking, filter the extract through qualitative filter paper (medium speed, pore size 15–20 μm). Discard the first 10 mL of initial filtrate and collect the subsequent filtrate as the test solution. Take a 9 cm diameter petri dish, place a piece of qualitative filter paper at the bottom, and accurately pipette 20 mL of the test solution to evenly moisten the filter paper.

[0135] Select plump and uniformly sized radish seeds (preferably new seeds with a germination rate of ≥85% of the current year; studies have shown that white radish seeds have the highest response to compost plant toxicity, r=0.96, and are the most representative in comprehensively characterizing compost maturity), and evenly place 50 seeds in a petri dish, with each seed spaced at least 5 mm apart.

[0136] The petri dishes were placed in a 25℃ constant temperature incubator and cultured in the dark for 72 hours. A control experiment was conducted simultaneously using ultrapure water instead of compost extract. Three replicates were set up for each group, and the average value was taken as the final result. After cultivation, germination was defined as a root length ≥2mm. The root length of each seed (measured from the base to the tip) was measured using vernier calipers (accuracy 0.1mm). The germination index (GI) was calculated using the following formula:

[0137] GI = Sample germination rate × Sample average root length × Control germination rate × Control average root length × 100%

[0138] When the GI is greater than 80%, the compost is considered to be fully decomposed and non-toxic to plants; if the GI is greater than 50% but less than 80%, it indicates that the compost is basically decomposed but not yet fully stable, and the aging time needs to be extended by 3 to 5 days before retesting; if the GI is less than 50%, it indicates that the compost is not fully decomposed and needs to be returned for fermentation treatment.

[0139] Well-rotted compost products with a glycated index (GI) greater than 80% are first fed into a drum screen via a belt conveyor for screening. The drum screen has a screen mesh size of 5mm, a screen body inclination angle of 3° to 5°, and a rotation speed of 20 to 30 r / min.

[0140] The undersize material (fine material with a particle size ≤ 5mm) is used as the base material for powdered organic fertilizer; the oversize material (coarse material with a particle size > 5mm, mainly uncomposted coarse fibers and impurities) is returned to the crushing process in step S1 for reprocessing, or used as a leavening agent for composting and reused in the next batch of composting ingredients.

[0141] The undersize material undergoes secondary crushing in a semi-wet material crusher. This crusher employs a vertical, multi-layered turbulent flow chain hammer structure, characterized by its resistance to wall adhesion and clogging. The output fineness is controlled at 60–100 mesh (0.15–0.25 mm). The crushed material undergoes quality inspection (indicators include organic matter content, total nutrient content, moisture content, pH value, heavy metal content, fecal coliform count, and ascaris egg mortality rate, etc.). If the material meets the requirements of the NY / T 525-2021 "Organic Fertilizer" standard, a powdered ecological organic fertilizer product is obtained.

[0142] To prepare granular organic fertilizer, the powdered product can be fed into a disc granulator for granulation, then dried (drying temperature controlled at 60-80℃, material moisture content reduced to ≤20%), cooled, and screened twice (screen mesh size 2-4mm) before being packaged and stored.

[0143] In one embodiment, experimental data are provided for the method of preparing ecological organic fertilizer by synergistic aerobic composting of the aforementioned Chinese herbal medicine residue and cow dung, as follows:

[0144] The test conditions include:

[0145] The raw material ratio (dry weight ratio) is livestock and poultry manure (cow manure): dehydrated vegetable waste: straw = 40:30:20, plus 10% of the total mass of the mixed materials as vegetable waste juice, initial C / N = 25:1, initial moisture content 60%;

[0146] The composting silo has four layers (top layer, middle layer 1, middle layer 2, and bottom layer), with an effective volume of approximately 26m³ per layer. 3 The amount of material laid in a single layer is approximately 22 tons;

[0147] The amount of compound microbial inoculant added is 1.2% of the total mass of the material;

[0148] The fermentation cycle is 12 days, with the material falling layer by layer (one layer falling every 3 days).

[0149] Table 1 shows the temperature changes of each layer during the composting process (unit: °C) (the measuring points for each layer are located at 1 / 3 and 2 / 3 of the height of the compost pile, and the average value is taken).

[0150]

[0151] Note: Day 0 data represents the initial state of each layer (the top layer is newly fed, and the other layers have been pre-fermented). The top layer reaches above 55℃ on day 2, meeting the temperature rise requirements; the middle layer maintains a high temperature period (above 60℃) for 5-7 days; the bottom layer temperature gradually decreases to near ambient temperature.

[0152] Table 2 shows the oxygen concentration (unit: %, volume fraction) of each layer during the composting process (the measuring point is located at the center height of the compost).

[0153]

[0154] The oxygen concentration in each layer was maintained within the control range of 8% to 15% during the active fermentation period (days 2 to 6). After day 7, it gradually rose, indicating that the oxygen consumption rate decreased and the cooling period began.

[0155] Table 3 shows the actual ventilation volume for each floor (unit: m³). 3 / h) and control deviation (based on real-time PLC adjustment, set values: top layer ≥478, middle layer ≥683, bottom layer ≥194);

[0156]

[0157] The ventilation volume of each floor fluctuates around the set value (within ±30%). During the high-temperature period (days 3 to 7), the oxygen demand is close to the upper limit, and then gradually decreases, which is consistent with the oxygen consumption trend.

[0158] Table 4 shows the change in moisture content of materials during composting (unit: %) (samples were taken from each layer and the average value was taken).

[0159]

[0160] The initial moisture content was about 60%. After 12 days of aerobic fermentation and forced ventilation, the moisture content of each layer of material was reduced to below 40%, meeting the requirements for subsequent aging.

[0161] Table 5 shows the composting indicators of different layers (tested after 7 days of aging);

[0162]

[0163] All the GI of the material discharged from each layer was greater than 80%, especially the bottom layer (91.2%), indicating that the material was fully decomposed after four layers of fermentation; all physical and chemical indicators met the standards for organic fertilizer.

[0164] Table 6 shows the effect of different raw material ratios on composting efficiency (comparative experiment) (with other conditions fixed, only the ratio of vegetable waste to manure was changed, and the bottom discharge GI and fermentation cycle were used as evaluation indicators).

[0165]

[0166] The optimal ratio is 40:30:20 (i.e., the preferred range of this invention), which has a moderate C / N ratio, the longest high-temperature period, the shortest fermentation cycle, the highest degree of decomposition (GI=91.2%), and the best moisture content control. An excessively high proportion of manure (low C / N ratio) can easily lead to ammonia inhibition, while an excessively high proportion of vegetable waste (high C / N ratio) results in an excess of carbon source, neither of which is conducive to rapid decomposition.

[0167] The above experimental data show that the method of the present invention, through layered independent aeration, step-by-step turning of materials, and tiered utilization of heat, can stably control the pile temperature (55-70℃), oxygen concentration (8%-15%), and moisture content (reduced from 60% to ≤40%), and complete aerobic fermentation within 12 days. The germination index of the final product seeds is higher than 80%, and all indicators meet the NY / T 525-2021 standard, verifying the effectiveness and repeatability of the method.

[0168] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A method for preparing ecological organic fertilizer using fruit and vegetable waste and livestock and poultry manure, characterized in that, The method includes: S1. Raw material pretreatment and proportioning: The fruit and vegetable waste is crushed, impurities removed, and dehydrated by squeezing, and the juice of the squeezed waste is collected for later use. Crop straw is crushed; dehydrated vegetable waste, crushed straw and fresh livestock and poultry manure are mixed at a dry weight ratio, and the vegetable waste juice is added to adjust the total carbon-nitrogen ratio and initial moisture content of the mixture. After stirring evenly, the mixture is obtained. S2, Layered Filling and Inoculation: The mixture obtained in S1 is layered and filled into the top layer of the multi-layer aerobic composting bin, with each layer having a predetermined thickness of material; during the material laying process, compound microbial agents are sprayed onto each layer of material; S3, Layered Independent Aeration: Aeration pipes buried inside each layer of the pile body provide independent oxygen supply to each layer of the pile body; Different ventilation parameters are set according to the different fermentation stages of each layer of the stack, and the ventilation of each layer is independently adjusted based on the real-time feedback signal of oxygen concentration in each layer. S4. Layered turning and layer-by-layer feeding: During the composting fermentation process, the eccentric turning feeder at the bottom of each layer of aerobic composting bins is turned periodically, so that the material in the upper layer is evenly scattered into the next layer of aerobic composting bins under the action of gravity, realizing the layer-by-layer turning from top to bottom. The material passes through each compartment from top to bottom and then falls to the bottom for discharge. S5. Multi-parameter real-time monitoring and automatic control: Collect temperature, oxygen concentration and / or gas concentration data of each layer of the stack, compare and analyze the collected real-time data with preset thresholds, and automatically adjust the ventilation volume and / or turning frequency according to the comparison results. S6. High-temperature aerobic fermentation: The mixed materials undergo three stages in sequence in the multi-layer aerobic composting chamber: heating period, high-temperature period and cooling period, to complete aerobic fermentation. S7. Aging and Post-processing: The compost products obtained in S6 are aged and, after passing the test, ecological organic fertilizer is obtained.

2. The method for preparing ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure according to claim 1, characterized in that, In step S1, the dehydrated vegetable waste, crushed straw, and fresh livestock and poultry manure are mixed at a dry weight ratio of (30-50):(20-40):(10-30); the amount of vegetable waste juice added is 5%-15% of the total mass of the mixture. The total carbon-nitrogen ratio of the mixture is adjusted to 20:1 to 30:1, and the initial moisture content is adjusted to 55% to 65%.

3. The method for preparing ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure according to claim 1, characterized in that, In S2, the multi-layer aerobic composting bin consists of 4 to 6 independent bins stacked vertically, with materials fed from the top layer and moving downwards layer by layer. The thickness of each layer of material is 0.8 to 1.2 m; the amount of the compound microbial agent added is 0.5% to 2.0% of the total mass of the mixture.

4. The method for preparing ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure according to claim 1, characterized in that, In S3, the aeration pipe is located at 1 / 3 of the height of each layer of the pile, and several ventilation holes are opened on the circumference of the pipe, with the opening direction of the ventilation holes being obliquely downward. The differentiated ventilation parameters are set according to the fermentation stage of each floor: the ventilation volume of the top floor during the heating period is not less than 478m³. 3 / h, the ventilation volume of the intermediate layer during the high-temperature period shall not be less than 683m³ / h. 3 / h, the ventilation volume of the ground floor during the cooling period should not be less than 194m³ / h. 3 / h.

5. The method for preparing ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure according to claim 4, characterized in that, In S3, the method of independently adjusting the ventilation volume is as follows: when the oxygen concentration of a certain layer is lower than the preset lower limit, the ventilation volume of that layer is increased; When the oxygen concentration is higher than the preset upper limit, reduce the ventilation volume of that floor; When the oxygen concentration is within the preset range, the current ventilation parameters remain unchanged; Meanwhile, when the temperature of a certain layer of the stack exceeds the preset temperature threshold, the ventilation volume of that layer is increased to assist in heat dissipation, based on the oxygen concentration control.

6. The method for preparing ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure according to claim 1, characterized in that, In S4, the eccentric flipping feeder includes a flipping shaft and a flipping plate that flips around the flipping shaft. The central axis of the flipping plate in the radial direction of the flipping shaft is offset from the axis of the flipping shaft. An elastic grid is laid on the flap to support materials, and the grid flips synchronously with the flap. Each flap is connected by a lever mechanism and driven by the same drive unit to achieve synchronous flipping.

7. The method for preparing ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure according to claim 1, characterized in that, In S4, the turning cycle is dynamically adjusted based on the feedback signals from the temperature sensor and the oxygen concentration sensor: when the pile temperature is higher than the first temperature threshold or the oxygen concentration is lower than the first oxygen threshold, the turning interval is shortened. When the pile temperature is within the suitable fermentation temperature range and the oxygen concentration is within the suitable fermentation oxygen range, extend the turning interval. Each time the material is turned over, the flip plate rotates to a predetermined angle, allowing the material to be evenly distributed to the next layer through the grid.

8. The method for preparing ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure according to claim 1, characterized in that, In S5, the real-time monitoring of multiple parameters includes: collecting temperature data at different locations along the height of each layer of the stack, oxygen concentration data at the center height of the stack, and ammonia and / or hydrogen sulfide concentration data. When the ammonia concentration exceeds the first ammonia threshold or the hydrogen sulfide concentration exceeds the first hydrogen sulfide threshold, the deodorization device will be automatically activated and the ventilation volume will be reduced.

9. The method for preparing ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure according to claim 1, characterized in that, In S6, the heating period is from day 0 to day 2, during which the pile temperature rises to above 55°C. The high-temperature period is from day 2 to day 9, and the temperature of the pile body is maintained above 60°C for 5 to 7 days. The cooling period is from day 9 to day 12, during which the temperature of the pile gradually decreases to 35 to 40°C; the entire fermentation cycle is 7 to 12 days.

10. The method for preparing ecological organic fertilizer by combining fruit and vegetable waste with livestock and poultry manure according to claim 1, characterized in that, In step S7, the aging process takes 7 to 14 days. After aging, the seed germination index of the compost products is tested. When the seed germination index is greater than 80%, the compost is considered to be fully decomposed. The decomposed compost products are screened and crushed to obtain ecological organic fertilizer.

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