Liquid manure fermentation dynamic optimization control system and method

Abstract

The invention provides a liquid manure fermentation dynamic optimization control system and method. The system comprises a pretreatment module, a fermentation module, a dynamic regulation and control module, an aeration stirring module, an environment control module and a safety monitoring module. Wherein the pretreatment module comprises a solid-liquid separation unit, a PH regulation unit and an impurity interception unit; the fermentation module comprises a sectional fermentation tank group and an inter-tank conveying system; the dynamic regulation and control module comprises a parameter sensing array and an aeration rate regulating valve group; the aeration stirring module comprises a suspended aeration unit and a mechanical-pneumatic dual-mode stirrer; the environment control module comprises a heat exchange system and a humidity maintaining unit; the safety monitoring module comprises a gas early warning subsystem and a pressure balancing device, and a three-in-one technical route of'multi-mode sensing, staged regulation and control and energy closed loop 'is provided to solve the two core problems of insufficient dynamic adaptability and low system energy efficiency in the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of manure fermentation, and particularly to a dynamic optimization control system and method for liquid manure fermentation. Background Art

[0002] Traditional systems mostly adopt single-functional modules (such as independent temperature control, stirring, or solid-liquid separation devices), lacking cross-module linkage control. The efficiency of static control devices is low:

[0003] Single temperature control module: Traditional fermentation systems are only equipped with 1-2 temperature probes (usually located in the middle of the tank), resulting in a temperature difference of >5°C between material layers. For example, when the concentration >10%, the temperature at the bottom of the material is too high due to deposition (up to 50°C), while the temperature of the upper layer is only 38°C, leading to local rancidity.

[0004] Disconnection between stirring and gas monitoring: Most devices adopt timed stirring or fixed rotation speed mode, unable to dynamically adjust according to gas components (CH4, H2S). Continuous full-speed stirring increases energy consumption by 40% and destroys the microbial floc structure.

[0005] Limited sensor functions: Existing systems only monitor temperature or pH value, lacking real-time feedback on material concentration (TS) and gas components.

[0006] Serious energy and resource waste:

[0007] Heat energy loss: The thermal efficiency of traditional heating systems (such as single bottom coil) is only 60-70%, and the waste heat of fermentation is not recovered.

[0008] Low utilization rate of biogas slurry: Approximately 30% of the liquid after solid-liquid separation needs secondary treatment, and a closed-loop utilization system is not formed. Summary of the Invention

[0009] The present invention provides a dynamic optimization control system and method for liquid manure fermentation, and proposes a three-in-one technical route of "multi-modal perception - staged regulation - energy closed-loop" to solve the two core problems of insufficient dynamic adaptability and low system energy efficiency in the background art. The optimization breakthrough is specifically achieved through the following system structure and control method. The solution is as follows:

[0010] 1. A dynamic optimization control system for liquid manure fermentation, comprising a pretreatment module, a fermentation module, a dynamic regulation module, an aeration and agitation module, an environmental control module, and a safety monitoring module; wherein, the pretreatment module includes a solid-liquid separation unit, a pH adjustment unit, and an impurity interception unit; the fermentation module includes a segmented fermentation tank group and an inter-tank conveying system; the dynamic regulation module includes a parameter sensing array and an aeration volume regulating valve group; the aeration and agitation module includes a suspended aeration unit and a mechanical-pneumatic dual-mode stirrer; the environmental control module includes a heat exchange system and a humidity maintenance unit; the safety monitoring module includes a gas warning subsystem and a pressure balance device.

[0011] Preferably, the solid-liquid separation unit includes a screw extruder and an inclined screen, and the separation efficiency is ≥95%; the pH adjustment unit is specifically an automatic acid-base agent dosing device for linking with a conductivity sensor; the impurity interception unit includes a double-layer filter screen with a pore size of 1-5 mm and an ultrasonic cleaning component.

[0012] Preferably, the segmented fermentation tank group includes a hydrolysis acidification tank, a main fermentation tank, and a post-ripening tank; the inter-tank conveying system: a pneumatic diaphragm pump and an anti-blocking pipeline, wherein the anti-blocking pipeline is lined with a ceramic coating.

[0013] Preferably, the parameter sensing array deploys a number of distributed sensors for dissolved oxygen, temperature, pH, and oxidation-reduction potential (ORP); the aeration volume regulating valve group includes a Venturi injector and a microporous aeration pipe, and the aeration accuracy is ±5%.

[0014] Preferably, the suspended aeration unit includes a spiral aeration pipe and an anti-tangling floating ball; the mechanical-pneumatic dual-mode stirrer includes top paddle stirring + bottom air-lift circulation.

[0015] Preferably, the heat exchange system includes a ground-source heat pump and a fermentation waste heat recovery device; the humidity maintenance unit includes atomizing spraying and condensate reflux structure; the gas warning subsystem includes a methane, hydrogen sulfide, and ammonia three-in-one detector; the pressure balance device includes a double safety valve and a bursting disc.

[0016] A dynamic optimization control method for liquid manure fermentation, the steps are as follows:

[0017] S1. Solid-liquid separation and impurity interception:

[0018] (1) Start the combined unit of the screw extruder and the inclined screen, and the liquid manure is initially filtered through the double-layer filter screen, and the separated liquid enters the buffer tank;

[0019] S2. Dynamic pH balance control:

[0020] (1) The conductivity sensor monitors the liquid conductivity in real time, and links with the automatic acid-base agent dosing device to control the pH value within 6.5-7.

[0021] (2) After adding, let it stand for 30 minutes, conduct a secondary calibration of the pH sensor, and trigger the compensation addition module when the deviation exceeds ±0.2, and cycle in turn.

[0022] S3. Hydrolysis and acidification stage:

[0023] (1) The hydraulic agitator runs for 10 minutes every 2 hours to prevent sediment accumulation;

[0024] (2) Monitor the pressure in the tank and start the pressure balancing device when the time limit exceeds 2 hours.

[0025] S4. Main fermentation stage:

[0026] (1) The aeration volume in the first 24 hours is set to 0.8 m 3 / (m 3 ·h), and a combination of a Venturi injector and a microporous aeration pipe is adopted;

[0027] (2) Active period of thermophilic bacteria (40 - 45 °C): Turn on the waste heat recovery device to maintain high-temperature degradation;

[0028] (3) Pathogen killing period (90 - 100 °C): Activate the cooling water circulation system;

[0029] S5. Post-ripening stage:

[0030] Intermittent aeration is 15 - 30 minutes / cycle, and the stop time is 45 - 90 minutes (on-off ratio 1:3 to 1:4);

[0031] S6. Qualified detection: Detect the parameters of the biogas slurry after aeration,

[0032] After passing the qualification, it is packaged and stored;

[0033] If it fails to pass the qualification, it will automatically flow back to the main fermentation tank, add a composite bactericide containing nitrifying bacteria and denitrifying bacteria for secondary treatment, and add a carbon source (straw powder) to adjust the C / N ratio.

[0034] Preferably, the NH3-N range of the biogas slurry quality is 5 - 50 mg / L, and the TP is 1 - 5 mg / L; the ultrasonic cleaning component automatically cleans the dirt once every 4 hours to prevent the filter screen from being blocked.

[0035] Preferably, the parameters of the hydrolysis and acidification tank are dissolved oxygen: DO ≤ 0.5 mg / L, ORP < -200 mV; temperature: 35 ± 2 °C, maintained by the ground source heat pump system, with a fluctuation threshold of ±1 °C.

[0036] The advantages of the present invention are:

[0037] Efficient pretreatment

[0038] The pre - treatment module of the system has a clear division of labor. The combination of the screw extruder and the inclined screen in the solid - liquid separation unit has a separation efficiency of ≥95%, which can efficiently separate solid - liquid components. The double - layer filter screen and the ultrasonic cleaning component can intercept impurities and prevent blockages, ensuring the stability of the subsequent treatment process. The pH adjustment unit is linked with the acid - base agent automatic dosing device through a conductivity sensor, which can accurately control the pH value within 6.5 - 7, and the secondary verification mechanism ensures the dynamic balance of pH.

[0039] Advantages of segmented fermentation

[0040] The segmented fermentation tank group includes a hydrolysis - acidification tank, a main fermentation tank, and a post - ripening tank, which can provide a suitable environment according to the requirements of different stages. In the hydrolysis - acidification stage, the hydraulic pusher prevents sediment accumulation, and the pressure balance device ensures safety. In the main fermentation stage, different aeration volumes and temperature control strategies are adopted at different times. For example, in the active period of thermophilic bacteria, the waste heat recovery device is utilized, and in the pathogen - killing period, the cooling water circulation system is activated to improve fermentation efficiency and quality. In the post - ripening stage, intermittent aeration optimizes the on - off ratio, which helps to improve the quality of biogas slurry.

[0041] Precise regulation and safety guarantee

[0042] The parameter sensing array of the dynamic regulation module can real - time monitor parameters such as dissolved oxygen and temperature. The aeration accuracy of the aeration volume regulating valve group reaches ±5%, realizing precise aeration. The suspended aeration unit and the mechanical - pneumatic dual - mode stirrer of the aeration and stirring module make the fermentation more uniform. The heat exchange system and the humidity maintenance unit of the environmental control module can effectively control the fermentation environment. The gas warning subsystem of the safety monitoring module can real - time monitor harmful gases, and the pressure balance device ensures the safety of the fermentation process.

[0043] Quality control and resource utilization

[0044] Parameters of the biogas slurry after aeration are detected. If qualified, it is packaged and stored; if unqualified, it is re - treated to ensure the quality of the biogas slurry. The ranges of NH3 - N and TP meet the standards, and the C / N ratio can also be adjusted by adding a carbon source. At the same time, the fermentation waste heat recovery device realizes resource recycling and reduces energy consumption. Specific implementation manners

[0045] In order to make the purpose and advantages of the present invention clearer, the present invention will be further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0046] Those skilled in the art should understand that these implementation manners are only used to explain the technical principle of the present invention and do not limit the protection scope of the present invention.

[0047] Implementation plan of the pre - treatment stage

[0048] Solid - liquid separation and impurity interception

[0049] Start the screw extruder (working pressure 1.0 MPa) and the inclined screen with a 15° inclination angle. When treating cow dung, the sieve mesh is adjusted to a double-layer pore size (upper layer 5 mm, lower layer 2 mm), and the separation efficiency is ≥95%.

[0050] The separated liquid is temporarily stored in the buffer tank, and the impurity interception unit starts ultrasonic cleaning (power density 0.4 W / cm 2 , and the cleaning cycle is 3 hours / time).

[0051] Response to emergencies: If the clogging rate of the filter screen > 30%, switch to the high-pressure water jet cleaning mode (pressure 2.5 MPa).

[0052] pH dynamic regulation

[0053] The conductivity sensor (range 0 - 20 mS / cm) monitors the liquid in real time, and lime milk (concentration 12%) is added in a linked manner to stabilize the pH at 6.8 - 7.0.

[0054] After standing for 30 minutes, when the secondary verification pH deviation > 0.2, the compensation module is triggered, and the additional dosing amount is 0.05 L / m 3 .

[0055] II. Process flow of the segmented fermentation stage

[0056] Operation of the hydrolysis acidification tank

[0057] The dissolved oxygen DO in the tank ≤ 0.3 mg / L, the ORP value is -230 mV, and the temperature is controlled at 34°C ± 1°C by the ground source heat pump.

[0058] The hydraulic pusher runs for 10 minutes every 2 hours (power 4 kW) to prevent sediment accumulation.

[0059] Safety control: When continuously operating for more than 2 hours or the pressure > 50 kPa, the double safety valves (pressure difference 8 kPa) automatically relieve pressure.

[0060] Control strategy of the main fermentation tank

[0061] Aeration in the first 24 hours: The throat velocity of the Venturi injector is 10 m / s, and the microporous aeration pipe (pore diameter 0.2 mm) provides an aeration volume of 0.8 m 3 / (m 3 ·h).

[0062] Thermophilic bacteria stage (42°C): The waste heat recovery device is started, and the heat exchange area to tank volume ratio is 1:8 to maintain the high-temperature degradation efficiency.

[0063] Pathogen inactivation (95°C): The cooling water circulation flow rate is 3 m 3 / h, and the temperature gradient of the tank body is controlled ≤ 2°C / hour.

[0064] Stirring mode: Alternating operation of top paddle stirring (20 rpm) + bottom air-lift circulation (air-liquid ratio 1:4).

[0065] Optimization of the post-ripening tank

[0066] Intermittent aeration cycle: 25 minutes on / 70 minutes off (on-off ratio 1:2.8), buoyancy of the suspended aeration unit adjusted to 1.0 kg / m 3 .

[0067] Atomizing spray (particle size 30 μm) runs for 5 seconds every 20 minutes, humidity maintained at 70% ± 5%.

[0068] III. Quality Monitoring and Safety Control

[0069] Detection standards for biogas slurry

[0070] Qualified indicators: NH3-N ≤ 20 mg / L (aquaculture standard), TP ≤ 3 mg / L, C / N ratio 28:1.

[0071] Treatment for unqualified: Return to the main fermentation tank, add nitrifying bacteria-Pseudomonas composite agent (0.2 g / L) + straw powder (C / N gap 0.6 units / ton).

[0072] Gas safety monitoring

[0073] Methane alarm threshold 0.8% LEL, hydrogen sulfide detection limit 0.08 ppm, functional test of double safety valves monthly.

[0074] Emergency response: When the gas exceeds the standard, the rupture disc (rupture pressure 110 kPa) starts first, and the standby ventilation system is activated synchronously.

[0075] IV. Equipment Operation and Maintenance and Data Management

[0076] Maintenance of key equipment

[0077] Daily inspection of the ceramic coating wear of the pneumatic diaphragm pump (working pressure 0.7 MPa), replace when the thickness < 1.2 mm.

[0078] Add high-temperature resistant grease (drop point ≥ 260 °C) to the mechanical stirring bearing every 500 hours.

[0079] Data acquisition system

[0080] Distributed sensor network (density 3 per m 3 ) Uploads dissolved oxygen and temperature data to the central control platform every 5 minutes.

[0081] Historical data storage period ≥ 3 years, abnormal data triggers a three-level early warning mechanism (yellow / orange / red).

[0082] Gas Safety Warning and Emergency Oxygenation

[0083] Gas Monitoring:

[0084] When the methane concentration > 5% LEL, hydrogen sulfide > 10 ppm, and ammonia > 20 ppm, the three-in-one detector triggers an audible and visual alarm 35;

[0085] When hydrogen sulfide exceeds the standard, the emergency oxygenation mode is activated (the aeration volume is increased to 2 times and lasts for 30 minutes) 9.

[0086] 3.2 Treatment for Exceeding Temperature and Pressure Limits

[0087] High-temperature out of control:

[0088] When the temperature > 55 °C, the cooling water circulation system is activated (the cooling rate ≥ 2 °C / min), and low-temperature biogas slurry is injected synchronously for buffering;

[0089] If the temperature continuously exceeds the limit for more than 5 minutes, the system automatically switches to the standby fermentation tank 10.

[0090] Pressure imbalance:

[0091] When the pressure in the tank > 0.05 MPa, the dual safety valves and rupture discs are redundantly depressurized, and the aeration valve group is closed synchronously 9.

[0092] Step Four: Closed-loop Management of Product Quality

[0093] 4.1 Determination of Biogas Slurry Compliance and Return Control

[0094] Detection Standards:

[0095] Biogas slurry quality: NH3-N ≤ 50 mg / L, TP ≤ 5 mg / L (meeting GB18596) 35;

[0096] Pathogen inactivation rate: Escherichia coli group ≤ 100 CFU / mL, Ascaris egg mortality rate ≥ 95% 9.

[0097] Treatment for Non-compliance:

[0098] Automatically return to the main fermentation tank, add a composite bacterial agent (containing nitrifying bacteria and denitrifying bacteria) for secondary treatment, and supplement a carbon source (straw powder) to adjust the C / N ratio 16.

[0099] 4.2 Resource Utilization and Equipment Maintenance

[0100] Biogas slurry utilization: After being diluted by the atomizing spray unit, calculate the safe application rate according to the NY / T3958 standard and use it for farmland irrigation 5;

[0101] System self-cleaning:

[0102] After each batch of fermentation is completed, start the ultrasonic cleaning component and the ceramic coating pipeline flushing program to prevent biofilm attachment

[0103] Alternative implementation supplement:

[0104] 1. Pretreatment module

[0105] Replacement scheme for solid-liquid separation unit

[0106] A drum screen (screen hole diameter 1.5 - 3 mm, rotation speed 25 - 35 rpm) can be optionally used to replace the combination of screw extruder and inclined screen 4, and a scraper slag cleaning device needs to be equipped to prevent screen hole blockage.

[0107] Engineering adaptation: For high-viscosity materials such as pig manure, it is recommended to use a stepped vibrating screen (amplitude 4 - 6 mm, frequency 15 Hz) to improve separation efficiency.

[0108] Replacement scheme for pH adjustment unit

[0109] Sodium bicarbonate powder (dosage 0.1 - 0.3 kg / m 3 ) can replace liquid acid-base agents, and a powder dissolution tank and a metering screw conveyor need to be added.

[0110] 2. Fermentation module

[0111] Replacement scheme for segmented fermentation tank group

[0112] The hydrolysis acidification tank can be made of fiberglass instead of stainless steel, and a biofilm carrier (specific surface area ≥ 500 m 2 / m 3 ) needs to be added to the inner wall to accelerate the acidification reaction.

[0113] Note: A tank body insulation layer (50 mm thick polyurethane) needs to be equipped to compensate for the difference in heat conduction of the materials.

[0114] Replacement scheme for inter-tank conveying system

[0115] Under the condition of high solid content (> 10%), it can be replaced by a hydraulic piston pump (pressure 1.2 - 1.5 MPa) combined with wear-resistant rubber pipes, which can withstand solid particles with a particle size ≤ 8 mm.

[0116] 3. Dynamic regulation module

[0117] Replacement scheme for parameter sensing array

[0118] For dissolved oxygen monitoring, a fluorescence sensor (response time < 10 s) can be optionally used to replace the traditional membrane electrode to avoid zero drift caused by hydrogen sulfide poisoning.

[0119] Replacement scheme for aeration volume adjustment

[0120] A rotary cutting aeration disk (aeration hole diameter 0.5 - 1 mm) can replace the microporous aeration pipe, which is suitable for the working condition with fiber impurities > 2%, and is equipped with a backwashing system (cycle 6 hours / time).

[0121] 4. Environmental control module

[0122] Heat exchange system replacement plan

[0123] An air source heat pump (COP≥3.8) can alternatively replace a ground source heat pump, and a buffer water tank (volume ratio 1:10) needs to be added to compensate for the thermal inertia.

[0124] II. Deep expansion of beneficial effects

[0125] 1. Multi-dimensional improvement of processing efficiency

[0126] A solid-liquid separation efficiency of ≥95% can reduce the sludge deposition in the subsequent fermenter by more than 40%, and extend the equipment cleaning cycle to 72 hours2;

[0127] The staged fermentation increases the organic matter degradation rate to 85% (only 65% in the traditional single tank), and the precise control of ORP in the hydrolysis acidification tank (-250~-200mV) promotes a 30% increase in the production of volatile fatty acids3.

[0128] 2. Optimization of energy consumption and resource recycling

[0129] The dynamic adjustment of the aeration volume (accuracy ±5%) reduces the energy consumption of the blower by 18 - 22%, and the waste heat recovery device makes the overall thermal efficiency of the system ≥70%1;

[0130] A condensate water reflux rate of ≥85% realizes a daily water saving of 3 - 5m 3 / hundred tons of treatment volume, and the straw powder addition amount is reduced by 15%6.

[0131] 3. Enhancement of safety and quality control

[0132] The dual-mode stirrer makes the material mixing uniformity (CV value) ≤12%, which is 50% higher than that of a single mechanical stirrer4;

[0133] The response time of the three-in-one gas detector is <3 seconds. Combined with a bursting disc (action error ±5kPa), a double explosion-proof barrier is constructed, and the accident rate is reduced to 0.05 times / year8.

[0134] 4. Intelligent upgrade of operation and maintenance

[0135] The wireless sensor network (packet loss rate <0.1%) realizes real-time mapping of the data of the tank group, and the fault diagnosis accuracy rate is increased to 92%5;

[0136] The three-level early warning mechanism (yellow / orange / red) shortens the abnormal condition handling time to within 15 minutes7.

[0137] III. Comparison of implementation effects in typical scenarios

[0138] This solution enhances the flexibility of equipment selection through modular replacement design (such as drum screens / fluorescent sensors, etc.), and realizes triple optimization of "efficiency - safety - cost" by combining segmented regulation and intelligent early warning, with a significant improvement in comprehensive benefits compared to traditional processes.

[0139]

[0140] So far, the technical solution of the present invention has been described in combination with the preferred embodiments. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A liquid manure fermentation dynamic optimization control system, characterized in that: It includes a pretreatment module, a fermentation module, a dynamic control module, an aeration and stirring module, an environmental control module, and a safety monitoring module; wherein the pretreatment module includes a solid-liquid separation unit, a pH adjustment unit, and an impurity interception unit; the fermentation module includes a segmented fermentation tank group and an inter-tank transportation system; the dynamic control module includes a parameter sensor array and an aeration volume regulating valve group; the aeration and stirring module includes a suspended aeration unit and a mechanical-pneumatic dual-mode agitator; the environmental control module includes a heat exchange system and a humidity maintenance unit; the safety monitoring module includes a gas early warning subsystem and a pressure balance device.

2. The liquid manure fermentation dynamic optimization control system according to claim 1 is characterized in that: The solid-liquid separation unit includes a screw extruder and an inclined screen, and the separation efficiency is ≥95%; the pH adjustment unit is specifically an automatic acid and alkali agent dosing device for linking the conductivity sensor; the impurity interception unit includes a double-layer filter with a pore size of 1-5mm and an ultrasonic cleaning component.

3. The liquid manure fermentation dynamic optimization control system according to claim 1 is characterized in that: The segmented fermentation tank group comprises a hydrolysis acidification tank, a main fermentation tank, and a post-ripening tank; the inter-tank transportation system comprises a pneumatic diaphragm pump and an anti-clogging pipeline, wherein the anti-clogging pipeline is lined with a ceramic coating.

4. The liquid manure fermentation dynamic optimization control system according to claim 1 is characterized in that: The parameter sensing array deploys a number of distributed sensors for dissolved oxygen, temperature, pH, and oxidation-reduction potential (ORP); the aeration volume regulating valve group includes a venturi ejector and a microporous aeration tube, and the aeration accuracy is ±5%.

5. The liquid manure fermentation dynamic optimization control system according to claim 1 is characterized in that: The suspended aeration unit includes a spiral aeration tube and an anti-entanglement suspension ball; the mechanical-pneumatic dual-mode agitator includes top paddle agitation + bottom air lift circulation.

6. The liquid manure fermentation dynamic optimization control system according to claim 1 is characterized in that: The heat exchange system includes a ground source heat pump and a fermentation waste heat recovery device; the humidity maintenance unit includes an atomization spray and a condensed water reflux structure; the gas warning subsystem includes a three-in-one detector for methane, hydrogen sulfide and ammonia; and the pressure balance device includes a double safety valve and a bursting disc.

7. A method for dynamic optimization control of liquid manure fermentation, characterized in that: Here are the steps: S1. Solid-liquid separation and impurity interception: (1) Starting the combined unit of the screw extruder and the inclined screen, the liquid feces and sewage are primarily filtered through the double-layer filter screen, and the separated liquid enters the buffer tank; S2.PH dynamic balance control: (1) The conductivity sensor monitors the liquid conductivity in real time and links the automatic acid and alkali agent dosing device to control the pH value at 6.5-7. (2) After addition, the pH sensor is calibrated for a second time after standing for 30 minutes. When the deviation exceeds ±0.2, the compensation dosing module is triggered and the cycle is repeated. S3. Hydrolysis and acidification stage: (1) The hydraulic flow booster is operated for 10 minutes every 2 hours to prevent sediment accumulation; (2) Monitor the pressure inside the tank and activate the pressure balancing device within a limited time if the pressure exceeds 2 hours. S4. Main fermentation stage: (1) The aeration volume for the first 24 hours is set to 0.8m 3 / (m 3 h) Combination of Venturi ejector and microporous aeration tube; (2) Thermophilic bacteria active period (40-45°C): Turn on the waste heat recovery device to maintain high temperature degradation; (3) Pathogen killing period (90-100°C): Activate the cooling water circulation system; S5. Post-ripening stage: Intermittent aeration is 15-30 minutes / cycle, and the stop time is 45-90 minutes (on-off ratio 1:3 to 1:4); S6. Qualified test: Parameter test of the aerated biogas slurry. After passing the test, the products will be packaged and stored; Those that fail to meet the standards will automatically flow back to the main fermentation tank, where they will be treated with a secondary bacterial agent containing nitrifying and denitrifying bacteria, and a carbon source (straw powder) will be added to adjust the C / N ratio.

8. The liquid manure fermentation dynamic optimization control method according to claim 7, characterized in that: The biogas slurry quality NH3-N ranges from 5 to 50 mg / L, and TP ranges from 1 to 5 mg / L; the ultrasonic cleaning component automatically cleans once every 4 hours to prevent the filter from being blocked.

9. The liquid manure fermentation dynamic optimization control method according to claim 7, characterized in that: The parameters of the hydrolysis acidification tank are dissolved oxygen: DO≤0.5mg / L, ORP<-200mV; temperature: 35±2°C, maintained by the ground source heat pump system, with a fluctuation threshold of ±1°C.

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