A control system and fermentation method for livestock and poultry manure and sludge cooperative fermentation

Abstract

The present application relates to the field of livestock manure treatment, and particularly relates to a livestock manure and sludge synergistic fermentation control system, comprising a raw material pretreatment unit, a mixing and blending unit, a fermentation reactor, a process monitoring and control module, a microbial intensive directional domestication subsystem, a leachate collection and treatment unit, and a central controller; a livestock manure and sludge synergistic fermentation method using the above system is also disclosed, comprising steps S1 raw material analysis and compounding, S2 multi-parameter coupled fermentation control, S3 aging, composting and post-treatment, etc. The present application solves the problem of single control logic in the prior art by integrating online near-infrared, heavy metal monitoring and other multi-dimensional sensors, and constructing a phased ventilation and stirring synergistic control model. The system can adaptively adjust the control weights of oxygen concentration and pH value according to the fermentation process, realizing a leap from single factor adjustment to multi-factor synergistic optimization, and accurately maintaining the optimal ecological niche of the fermentation system.

Description

Technical Field

[0001] This invention belongs to the field of livestock and poultry manure treatment, specifically relating to a control system and fermentation method for the co-fermentation of livestock and poultry manure and sludge. Background Technology

[0002] With the continuous expansion of livestock and poultry farming and urban sewage treatment, the amount of livestock and poultry manure and sludge produced has increased dramatically. How to achieve the synergistic treatment and resource utilization of these two types of organic waste has become a research hotspot in the field of environmental engineering. Aerobic fermentation technology is widely used in the treatment of sludge and livestock and poultry manure because it can stabilize, render harmless, and reduce the volume of organic matter and convert the final product into usable bio-organic fertilizer.

[0003] In the prior art, various processes and equipment have been developed for the synergistic aerobic fermentation treatment of livestock and poultry manure and sludge. Chinese invention patent application number 2022105117891 discloses a high-temperature aerobic fermentation system for synergistic treatment of sludge and livestock and poultry manure. By setting up complex cooling auxiliary mechanisms and control auxiliary components, it solves the problem of shortened optimal fermentation time due to excessively high temperatures during fermentation. This solution focuses on using mechanical structures to physically cool the incoming air to regulate the reaction temperature. Chinese invention patent application number 2008100401660 discloses a low-energy-consumption, pollution-free high-temperature aerobic fermentation process for sludge. It crushes the material into fine particles to reduce ventilation resistance and achieves low-energy operation and harmlessness by controlling parameters such as air pressure and temperature maintenance time.

[0004] However, existing technologies generally suffer from the following problems: First, the control logic of existing technologies is relatively simple, mainly focusing on single-factor adjustments such as temperature or ventilation, lacking the ability to monitor and coordinate the coupled changes of multiple parameters such as carbon-nitrogen ratio, pH value, oxygen concentration, microbial activity, and heavy metal ion concentration in real time, making it difficult to accurately maintain the optimal ecological niche of the fermentation system. Second, there is a lack of in-situ passivation and targeted microbial enhancement methods to address the potential heavy metal contamination risks during fermentation, leading to safety hazards in the product. The overall process stability and fermentation efficiency still have significant room for improvement. Therefore, overcoming these technical problems and deficiencies is a key issue that needs to be addressed. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects described in the background art, thereby realizing a control system for the co-fermentation of livestock and poultry manure and sludge, so as to solve the problems of single control logic, inability to achieve precise control of multiple parameters, lack of effective means to deal with heavy metal pollution, and low degree of resource utilization in the prior art.

[0006] To achieve the above-mentioned objectives, the technical solution of this invention is as follows:

[0007] A control system for the co-fermentation of livestock and poultry manure and sludge includes:

[0008] The raw material pretreatment unit is used to receive and test the input livestock and poultry manure and sludge to obtain their physicochemical properties.

[0009] A mixing and blending unit, connected to the raw material pretreatment unit, is used to generate a mixed substrate by adjusting the mass mixing ratio of feces and sludge based on a target carbon-nitrogen ratio range.

[0010] The fermentation reactor is equipped with temperature control, stirring and aeration devices for receiving the mixed substrate and carrying out aerobic fermentation.

[0011] The process monitoring and control module includes a temperature sensor, a pH sensor, an oxygen concentration sensor, an online near-infrared spectrometer, and a heavy metal monitoring module installed in the fermentation reactor, which are used to monitor fermentation process parameters in real time.

[0012] A microbial enhancement and acclimatization subsystem is connected to the fermentation reactor for enriching and / or acclimatizing functional microorganisms and for returning the acclimatized microorganisms to the fermentation reactor.

[0013] The leachate collection and treatment unit is used to collect the leachate generated at the bottom of the fermentation reactor and, based on its water quality test results, to partially or wholly reuse it in the mixing and blending unit to adjust the moisture content of the materials, or to transport it to the wastewater treatment system.

[0014] The central controller is electrically connected to each of the aforementioned units and modules. The central controller is configured to execute fermentation control logic containing multi-parameter coupling and condition judgment to trigger the microbial enhanced directional domestication subsystem based on the real-time data of the process monitoring and control module, so as to coordinately regulate the fermentation process.

[0015] Preferably, the process monitoring and control module includes a temperature sensor, a pH sensor, an oxygen concentration sensor, an online near-infrared spectrometer, and a heavy metal monitoring module.

[0016] The central controller uses the effective carbon-nitrogen ratio of the mixed substrate predicted in real time by the online near-infrared spectrometer. ,when With the set target value When the deviation exceeds a preset threshold, the mixing and blending unit or the auxiliary material addition device is controlled to automatically adjust the carbon-nitrogen ratio.

[0017] The microbial enhanced acclimatization subsystem includes a bypass acclimatization reactor, which gradually increases the concentration of heavy metal ions in the culture medium through a batch fed-batch culture method over a time series, for the targeted screening and expansion of thermophilic microbial agents with heavy metal tolerance.

[0018] This invention also discloses a method for co-fermenting livestock and poultry manure and sludge using the above-mentioned co-fermentation control system, comprising the following steps:

[0019] Step S1, Raw Material Analysis and Compatibility: The physicochemical properties of livestock and poultry manure and sludge are tested. The mixing ratio is calculated based on the carbon-nitrogen ratio balance principle, and the mixture is then thoroughly mixed according to the calculated ratio. The target carbon-nitrogen ratio... The range is 22~28.

[0020] Step S2, Multi-parameter coupled fermentation control: In the first control stage, the ventilation volume is adjusted based on the temperature deviation using a ventilation volume control model; in the second control stage, the stirring rate is synergistically regulated based on oxygen concentration and pH value.

[0021] Step S3, aging, composting and post-processing: Maintain the fermentation temperature within the range of 55~65℃ for high-temperature composting and maintain it for no less than 5 days. When the preset composting degree judgment conditions are met, the fermentation is terminated, and the discharged material is transferred to the aging area for secondary aging. The aged material is processed into organic fertilizer products through screening and crushing processes.

[0022] In step S2:

[0023] The ventilation volume control model for the first control stage is as follows:

[0024] .

[0025] in, Ventilation volume, unit: m³ / h; The target temperature is defined as 55~65℃. The measured temperature is in °C. The base ventilation rate is taken as 0.05~0.15 m³ / (h·m³ of material); The volume of the material is in m³. This is a proportionality coefficient, with a value ranging from 0.05 to 0.15 (unit: (m³ / h) / (℃·m³ material)).

[0026] The stirring rate control model for the second control stage is as follows:

[0027] ;

[0028] in, The stirring rate is expressed in r / min. The base stirring rate is expressed in r / min. and These are dimensionless weighting coefficients; To set the oxygen concentration, the value range is 8% to 18%; The measured oxygen concentration is expressed in % (%). The optimal pH value is between 7.5 and 8.5. The allowable pH fluctuation bandwidth is defined as 0.3 to 0.8.

[0029] Weighting coefficients in the second control phase and Based on fermentation days Make dynamic adjustments:

[0030] , ;

[0031] in, This represents the total number of days in the fermentation cycle. and The initial influence coefficient, and , When fermentation days Exceeding the total cycle At that time, take , .

[0032] In addition, it also includes the steps of in-situ passivation of heavy metals and microbial enhancement: when the rate of increase of the concentration of free heavy metal ions in the material system in the fermentation reactor exceeds the preset threshold or the concentration exceeds the standard, when the temperature drops to the thermophilic stage of 45~55℃, the microbial enhancement and directional domestication subsystem is activated, and domesticated heavy metal resistant microbial agents and passivation materials are added to the fermentation reactor.

[0033] The heavy metal resistant microbial agent contains *Geobacillus stearothermophilus* and *Thermobifida fusca*.

[0034] The passivation material is modified biochar, and its preparation method includes: impregnating straw biochar in an iron salt solution, ultrasonically treating it for 30-60 minutes, and then pyrolyzing and activating it at a heating rate of 5-10℃ / min under a nitrogen atmosphere at 300-400℃ for 30-60 minutes, so that its surface is loaded with nanoscale... -Fe2O3 particles.

[0035] In step S1, the carbon-nitrogen ratio balance principle is calculated based on the measured fecal carbon content. Nitrogen content With sludge carbon content Nitrogen content Calculate the fecal mass fraction using the following formula. :

[0036] ;

[0037] in, , , , Expressed as a percentage of mass, with a non-zero denominator; the solution... The value is used as the initial blending ratio; when adding auxiliary materials, the carbon and nitrogen contributions of the auxiliary materials are incorporated into the above equation for recalculation.

[0038] In addition, it also includes a step of co-management of exhaust gas treatment and leachate: the exhaust gas generated during the fermentation process is collected and then passed into a spray tower containing leachate or clean water for washing to remove malodorous gases.

[0039] The circulating liquid from the spray tower is discharged periodically. After the water quality is tested, the central controller decides whether to return all or part of the liquid after solid-liquid separation to the mixing and blending unit to replace part of the clean water based on the real-time moisture content and carbon-nitrogen ratio of the material in the fermentation reactor and the conductivity of the recycled liquid. When the EC value of the recycled liquid exceeds the crop tolerance threshold, the remaining part is discharged into the sewage treatment system.

[0040] The control system for the co-fermentation of livestock and poultry manure and sludge of the present invention has the following beneficial effects:

[0041] 1. The control system for the co-fermentation of livestock and poultry manure and sludge of this invention integrates multi-dimensional sensors such as online near-infrared sensors and heavy metal monitoring, and constructs a phased ventilation and stirring co-control model. In particular, it introduces a weighting coefficient that dynamically adjusts with fermentation time, solving the problem of the single control logic in existing technologies. The system can adaptively adjust the control weights of oxygen concentration and pH value according to the fermentation process, achieving a leap from single-factor regulation to multi-factor synergistic optimization, and precisely maintaining the optimal ecological niche of the fermentation system.

[0042] 2. This invention establishes a closed-loop control mechanism for heavy metal risk, encompassing monitoring, early warning, and response. By selectively screening heavy metal-tolerant functional microorganisms (such as *Bacillus steatophilus*) through a bypass acclimation subsystem, and combining this with nano-γ-Fe₂O₃-modified biochar possessing high adsorption capacity, a synergistic passivation effect between materials and microorganisms is achieved. This effectively inhibits the risk of heavy metal migration into the final product, ensuring the agricultural safety of organic fertilizer products and filling a gap in existing technologies for addressing heavy metal pollution.

[0043] 3. This invention constructs a closed-loop resource recovery system with gas-liquid coupling through exhaust gas treatment and leachate co-management steps. Leachate is used as the exhaust gas scrubbing liquid, achieving "waste-to-waste treatment," and the nutrient-rich scrubbing liquid is intelligently recycled to the blending unit based on the material's moisture content, carbon-nitrogen ratio, and conductivity. This significantly reduces the system's fresh water consumption and wastewater discharge, greatly improving the overall resource utilization rate and environmental friendliness of the process. Detailed Implementation

[0044] The present invention will now be described in more detail through specific embodiments.

[0045] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship shown, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0046] Example 1

[0047] This embodiment discloses a control system for the co-fermentation of livestock and poultry manure and sludge. By integrating raw material pretreatment analysis, dynamic allocation based on carbon-nitrogen ratio balance, process monitoring and control module equipped with multi-parameter sensors (including temperature, pH, oxygen, near-infrared spectroscopy and heavy metal monitoring), microbial enhanced acclimatization subsystem, leachate collection and treatment unit, and central controller, a co-fermentation control system capable of executing multi-parameter coupled fermentation control logic is constructed. This solves the problems of single control logic, inability to achieve precise multi-parameter co-fermentation control, lack of effective means to deal with heavy metal pollution, and low degree of resource utilization in the prior art.

[0048] The control system for the co-fermentation of livestock and poultry manure and sludge in this embodiment includes:

[0049] The raw material pretreatment unit is used to receive and test the input livestock and poultry manure and sludge to obtain their physicochemical properties.

[0050] A mixing and blending unit, connected to the raw material pretreatment unit, is used to generate a mixed substrate by adjusting the mass mixing ratio of feces and sludge based on a target carbon-nitrogen ratio range.

[0051] The fermentation reactor is equipped with temperature control, stirring and aeration devices for receiving the mixed substrate and carrying out aerobic fermentation.

[0052] The process monitoring and control module includes a temperature sensor, a pH sensor, an oxygen concentration sensor, an online near-infrared spectrometer, and a heavy metal monitoring module installed in the fermentation reactor, which are used to monitor fermentation process parameters in real time.

[0053] A microbial enhancement and acclimatization subsystem is connected to the fermentation reactor for enriching and / or acclimatizing functional microorganisms and for returning the acclimatized microorganisms to the fermentation reactor.

[0054] The leachate collection and treatment unit is used to collect the leachate generated at the bottom of the fermentation reactor and, based on its water quality test results, to partially or wholly reuse it in the mixing and blending unit to adjust the moisture content of the materials, or to transport it to the wastewater treatment system.

[0055] The central controller is electrically connected to each of the aforementioned units and modules. The central controller is configured to execute fermentation control logic containing multi-parameter coupling and condition judgment to trigger the microbial enhanced directional domestication subsystem based on the real-time data of the process monitoring and control module, so as to coordinately regulate the fermentation process.

[0056] In this embodiment, a precise and coordinated control of the entire aerobic fermentation process is achieved by constructing an integrated intelligent architecture. The system uses a central controller as its decision-making core. Basic physicochemical data is acquired through the raw material pretreatment unit, and the initial substrate is generated by the mixing and blending unit based on the carbon-nitrogen ratio balance principle. During the fermentation stage, the process monitoring and control module integrates temperature, pH, and oxygen concentration sensors, as well as an online near-infrared spectroscopy analyzer and a heavy metal monitoring module to capture multiple dynamic parameters of the fermentation system in real time. The central controller then executes preset multi-parameter coupled control logic based on this multi-dimensional data, performing correlation analysis on real-time carbon-nitrogen ratio, oxygen concentration, and temperature, and accordingly coordinating the control of temperature, stirring, and aeration devices. Simultaneously, it autonomously determines whether to trigger the microbial enhancement and acclimatization subsystem to recirculate functional microorganisms into the reactor to cope with environmental stress. Furthermore, the system can also determine the reuse path of the leachate based on the water quality test results. Through this closed-loop control system, the stability, efficiency, and safety of the fermentation process are significantly improved. Compared to existing temperature control methods that focus solely on physical cooling through mechanical structures, this embodiment proposes a more precise temperature regulation through the coordinated operation of multi-parameter real-time monitoring and central integrated control. This approach can respond to complex biochemical changes during fermentation, achieving a leap from single-factor regulation to multi-factor synergistic optimization. It effectively solves the problem of maintaining the optimal fermentation niche due to a single control logic. At the same time, through microbial enhancement and leachate reuse mechanisms, the system's in-situ response to pollution risks such as heavy metals and its resource utilization level are enhanced, thereby ensuring the harmlessness and stabilization of fermentation products.

[0057] To achieve real-time prediction of the effective carbon-to-nitrogen ratio of the mixed substrate, the process monitoring and control module includes a temperature sensor, a pH sensor, an oxygen concentration sensor, an online near-infrared spectrometer, and a heavy metal monitoring module; the central controller uses the real-time prediction of the effective carbon-to-nitrogen ratio of the mixed substrate from the online near-infrared spectrometer. ,when With the set target value When the deviation exceeds a preset threshold, the mixing and blending unit or the auxiliary material addition device is controlled to automatically adjust the carbon-nitrogen ratio.

[0058] In this embodiment, the system integrates an online near-infrared spectroscopy analyzer into the process monitoring and control module to achieve real-time prediction of the effective carbon-nitrogen ratio of the mixed substrate. The near-infrared spectroscopy analyzer can quickly acquire the characteristic spectral information of organic matter in the material and calculate the effective carbon-nitrogen ratio of the current mixed substrate in real time based on a pre-established model. The central controller compares this real-time value with the set target value. The comparison process automatically determines that the carbon-nitrogen ratio needs correction once a deviation exceeds a preset threshold. It then sends instructions to the mixing and blending unit or auxiliary material addition device, adjusting the mixing ratio of feces and sludge or adding additional high-carbon / high-nitrogen auxiliary materials to precisely restore the system's carbon-nitrogen ratio to the target range. This process upgrades carbon-nitrogen ratio control from offline detection and manual intervention to online monitoring and automatic response, significantly improving the timeliness and accuracy of control. This embodiment, by introducing online near-infrared technology and closed-loop feedback control, addresses the technological gap in existing technologies that cannot adjust the chemical ratio of materials in real time according to the fermentation process. This ensures that the microorganisms are in a suitable carbon-nitrogen nutrient environment throughout the entire fermentation cycle, providing a crucial guarantee for a stable and efficient aerobic fermentation process.

[0059] In addition, the microbial enhanced acclimatization subsystem includes a bypass acclimatization reactor, which gradually increases the concentration of heavy metal ions in the culture medium through a batch fed-batch culture method over a time series, for targeted screening and expansion of thermophilic microbial agents with heavy metal tolerance.

[0060] In this embodiment, the microbial enhanced targeted acclimatization subsystem constructs a functional microbial acclimatization and expansion loop independent of the main fermentation reactor by setting up a bypass acclimatization reactor. The bypass reactor in this embodiment employs a time-series batch-feed culture method. That is, in a culture cycle, a culture medium with a low concentration of heavy metal ions is initially used. As the microorganisms grow and adapt, higher concentrations of heavy metal ions are gradually added to the culture system. This allows for the targeted enrichment and screening of thermophilic microbial strains capable of tolerating high concentrations of heavy metal stress under continuously increasing selection pressure, and their numbers are expanded through continuous batch culture. Through this process, proactive biological intervention against potential heavy metal risks in the fermentation system is achieved. When the process monitoring module in the main fermentation reactor detects an increase in the concentration of free heavy metal ions or inhibition of microbial activity, the central controller triggers the system to return the bypass-acclimatized microbial agents with specific tolerance capabilities to the main reactor. This rapidly enhances the stress resistance and ecological stability of the fermentation system, ensuring the continuous and efficient operation of the high-temperature aerobic fermentation process.

[0061] Based on the adaptive evolution and resistance gene enrichment of microbial communities under sublethal selection pressure, the target functional microbial community can be obtained efficiently by artificially controlling the concentration gradient of stress factors in the culture environment. Compared with the method of relying on natural succession or the addition of commercial microbial agents, it has stronger targeting and better process compatibility, and can effectively deal with fermentation abnormalities caused by batch fluctuations of raw materials or heavy metal accumulation.

[0062] Example 2

[0063] The similarities to the above embodiments will not be repeated, the differences are as follows:

[0064] This embodiment discloses a method for co-fermenting livestock and poultry manure and sludge using the co-fermentation control system of embodiment one, specifically including the following steps:

[0065] Step S1, Raw Material Analysis and Compatibility: The physicochemical properties of livestock and poultry manure and sludge are tested. The mixing ratio is calculated based on the carbon-nitrogen ratio balance principle, and the mixture is then thoroughly mixed according to the calculated ratio. The target carbon-nitrogen ratio... The range is 22~28.

[0066] This step involves raw material analysis and compatibility based on the carbon-nitrogen ratio balance principle, aiming for the target carbon-nitrogen ratio. When the carbon-nitrogen ratio is set within the range of 22-28, the optimal carbon-nitrogen ratio for microbial growth and metabolism is typically 25-30:1. Excessive nitrogen concentration (e.g., pure straw) will lead to slow fermentation initiation, while insufficient nitrogen concentration (e.g., pure livestock manure) will easily cause nitrogen loss through ammonia volatilization. This step uses orthogonal experiments to verify that... The fermentation effect is best when the ratio is 25:1.

[0067] In this step, the carbon-nitrogen ratio balance principle is calculated based on the measured fecal carbon content. Nitrogen content With sludge carbon content Nitrogen content Calculate the fecal mass fraction using the following formula. :

[0068] ;

[0069] in, , , , Expressed as a percentage of mass, with a non-zero denominator; the solution... The value is used as the initial blending ratio; when adding auxiliary materials, the carbon and nitrogen contributions of the auxiliary materials are incorporated into the above equation for recalculation.

[0070] In this step, a carbon-nitrogen ratio calculation model based on mass balance is constructed to achieve precise matching of initial raw materials for the co-fermentation of livestock and poultry manure and sludge.

[0071] This embodiment uses the target carbon-nitrogen ratio. (22~28) are constraints, based on the measured fecal carbon content. Nitrogen content With sludge carbon content Nitrogen content Establish a linear equation in one variable to solve for the fecal mass fraction. The above formula is essentially a weighted average principle, which means that the ratio of the total carbon content of the mixture (the sum of the carbon contribution from feces and the carbon contribution from sludge) to the total nitrogen content (the sum of the nitrogen contribution from feces and the nitrogen contribution from sludge) must be equal to the target carbon-nitrogen ratio. By solving this equation, the initial blending ratio that meets the carbon-nitrogen ratio requirement can be obtained.

[0072] When auxiliary materials (such as straw, sawdust, etc.) are added, their carbon and nitrogen contributions are included as new terms in the numerator and denominator of the equation for recalculation, ensuring that the carbon-nitrogen ratio of the multi-component mixed system is accurately achieved. Through the above process, the traditional empirical proportioning is upgraded to a quantifiable mathematical model, realizing the standardization and precision of raw material compatibility, and laying a material foundation for the stable and efficient operation of the subsequent fermentation process.

[0073] The carbon-to-nitrogen ratio is one of the most critical factors affecting microbial metabolic activity during aerobic fermentation: carbon provides energy for microorganisms, while nitrogen is used to synthesize cellular proteins. If the temperature is too high (>35), the growth and reproduction of microorganisms will be limited due to insufficient nitrogen source, and fermentation will start slowly; if... If the nitrogen level is too low (<15), excess nitrogen is easily lost through volatilization as ammonia, resulting not only in fertilizer inefficiency but also in foul odor pollution. Relevant experiments are shown in Table 1 below:

[0074] Parameter categories Experimental methods / procedures Specific experimental data in conclusion Effect of carbon-nitrogen ratio on decomposition maturity Using sludge and pig manure as composting raw materials and sawdust as an auxiliary material, an aerobic composting experiment was conducted in a self-made semi-static forced ventilation composting reactor. Five treatments with gradients of 15, 20, 25, 30, and 35 were administered, with three replicates for each treatment. The reactor volume was 60 L, the forced aeration rate was 0.5 L / min·m³, and the fermentation period was 20 days. The pile temperature, pH, conductivity, and moisture content were monitored daily. After fermentation, the volatile solids degradation rate was measured. The T-value of the ratio (end point) With the initial (ratio) and seed germination index when At 25°C, the high-temperature period (≥55°C) lasted the longest, reaching 8 days; the volatile solids degradation rate was the highest, at 39.12%. The T-value was the lowest, at 0.53; the seed germination index reached 92%, significantly higher than that of other seeds. =20 (82%) =30 (78%) =35 (65%) and =15 (70%) The best aerobic composting method is to mix sludge and pig manure. 25 Feasibility of rapid determination of carbon and nitrogen content in livestock and poultry manure using near-infrared spectroscopy 120 livestock and poultry manure compost samples were collected from multiple provinces. Spectra were scanned in the 10000-4000 cm⁻¹ range using a near-infrared spectrometer (Spectrum OneNTS, Perkin Elmer). Partial least squares regression was used to establish quantitative calibration models for total organic carbon (TOC) and total nitrogen (TN). The samples were divided into calibration and validation sets, and the predictive power of the models was evaluated using the coefficient of determination (r²) and standard error. For fresh livestock and poultry manure compost samples, the near-infrared method showed the following prediction performance: TOC: r²=0.91, RPD=3.17 (validation set); TN: r²=0.97, RPD=6.11 (validation set); and relatively poor prediction performance for C / N: r²=0.83, RPD=2.39. Near-infrared spectroscopy can rapidly and accurately determine the total organic carbon and total nitrogen content in livestock and poultry manure. Feasibility of rapid determination of carbon and nitrogen content in cow manure using near-infrared spectroscopy Seventy-six manure samples were collected from major dairy farming areas. A quantitative calibration model for total nitrogen and total carbon was established using near-infrared reflectance spectroscopy. The optimal wavelength combination was selected using 19 filters, and a calibration equation was established using multiple regression. The model was then validated using 25 independent samples. The optimal regression equations used wavelengths for total nitrogen (2180, 2208, 2139, 2270, 2348 nm, 5 wavelengths) and total carbon (2208, 2180, 1680, 1778, 2230, 1445 nm, 6 wavelengths). Validation set correlation coefficients were 0.934 for total nitrogen and 0.971 for total carbon. The prediction standard deviations were 0.17% for total nitrogen and 1.45% for total carbon. Near-infrared spectroscopy can be used for the rapid determination of total nitrogen and total carbon in cow dung.

[0075] Table 1

[0076] Step S2, Multi-parameter coupled fermentation control: In the first control stage, the ventilation volume is adjusted based on the temperature deviation using a ventilation volume control model; in the second control stage, the stirring rate is synergistically regulated based on oxygen concentration and pH value.

[0077] Specifically, in this step:

[0078] The ventilation volume control model for the first control stage is as follows:

[0079] ;

[0080] in, Ventilation volume, unit: m³ / h; The target temperature is defined as 55~65℃. The measured temperature is in °C. The base ventilation rate is taken as 0.05~0.15 m³ / (h·m³ of material); The volume of the material is in m³. This is a proportionality coefficient, with a value range of 0.05 to 0.15 (unit: (m³ / h) / (℃·m³ material)).

[0081] The stirring rate control model for the second control stage is as follows:

[0082] ;

[0083] in, The stirring rate is expressed in r / min. The base stirring rate is expressed in r / min. and These are dimensionless weighting coefficients; To set the oxygen concentration, the value range is 8% to 18%; The measured oxygen concentration is expressed in % (%). The optimal pH value is between 7.5 and 8.5. The allowable pH fluctuation bandwidth is defined as 0.3 to 0.8.

[0084] This step achieves precise and intelligent control of the aerobic fermentation process by constructing a phased, multi-parameter coupled control model. The first phase employs a ventilation rate proportional control model based on temperature deviation. This model uses the material volume V as a baseline and sets the basic ventilation rate... proportional term to temperature deviation Combined, when the measured temperature Above the target temperature When the temperature is between 55 and 65°C, the ventilation volume is increased linearly to enhance heat dissipation and oxygen supply, thereby accelerating the cooling process. When the temperature is too low, the ventilation volume is reduced accordingly to avoid excessive heat loss.

[0085] The second stage involved constructing a coordinated control model for stirring rate based on oxygen concentration and pH value. This model uses a base stirring rate... Based on this, oxygen concentration deviation terms and pH deviation terms are introduced, and a dimensionless weighting coefficient is used. and The weighted coupling control logic is as follows: when the oxygen concentration deviates from the set range (8%~18%) or the pH value deviates from the optimal range (7.5~8.5), the stirring rate is dynamically adjusted to improve the mass transfer conditions and regulate the microbial metabolic environment, thereby achieving synergistic optimization of multiple parameters.

[0086] This process upgrades traditional single-parameter threshold control to multi-parameter continuous proportional control, significantly improving the fermentation process's response speed and control accuracy to environmental disturbances, and avoiding process fluctuations that may be caused by adjusting a single parameter. The ranges of each parameter are shown in Experiment Table 2 below:

[0087] Parameter categories Experimental methods / procedures Specific experimental data in conclusion Ventilation rate Design an aerobic fermentation experiment on food waste, setting ventilation rate gradients of 0.1, 0.2, 0.3, and 0.4 m³ / (h·m³ of material), and determine the changes in organic matter degradation rate and maturity. The optimal ventilation rate is 0.2 m³ / (h·m³ of material), corresponding to engineering parameters of approximately 0.05-0.15 m³ / (h·m³ of material). As ventilation volume increases, the peak temperature of the fermentation material rises, but the high-temperature period shortens. The organic matter degradation rate and maturity show a trend of first increasing and then decreasing, with the optimal fermentation effect observed at 0.2 m³ / (h·m³ material). Ventilation parameters Design an orthogonal experiment to analyze the effects of ventilation volume, moisture content, and C / N ratio on the aerobic fermentation of rural organic household waste. The optimal ventilation rate range is 0.148-0.173 m³ / d (equivalent to approximately 0.103-0.120 m³ / (h·m³ of material)). Ventilation volume is the most important factor determining fermentation results. Under this parameter combination, the fermentation products meet the GB8172-1987 agricultural control standards. Optimal pH value In high-density microbial culture experiments, the initial pH of the culture medium was set and the microbial growth was monitored. The optimal pH value is set at 7.5. For the cultivation and metabolism of aerobic microorganisms, maintaining a pH of around 7.5 is beneficial for cell growth and product synthesis.

[0088] Table 2

[0089] The experimental data above show that the target temperature range of 55~65℃, the oxygen concentration range of 8%~18%, the optimal pH range of 7.5~8.5, and the basic ventilation rate in the ventilation model set in this process can ensure the stable and efficient operation of the actual fermentation process.

[0090] Step S3, aging, composting and post-processing: Maintain the fermentation temperature within the range of 55~65℃ for high-temperature composting and maintain it for no less than 5 days. When the preset composting degree judgment conditions are met, the fermentation is terminated, and the discharged material is transferred to the aging area for secondary aging. The aged material is processed into organic fertilizer products through screening and crushing processes.

[0091] This step is based on the harmless treatment requirements of high-temperature aerobic fermentation. The high-temperature stage (55~70℃) can effectively kill pathogens, insect eggs and weed seeds. The fermentation temperature is maintained in the range of 55~65℃ for no less than 5 days. According to the "Technical Specification for Harmless Treatment of Livestock and Poultry Manure" (NY / T1168-2006), the purpose of harmless treatment of manure can be achieved by maintaining the fermentation temperature above 50℃ for more than 7 days. This can maximize the activity of microorganisms while reducing the emission of harmful gases.

[0092] In this embodiment, the co-fermentation method of livestock and poultry manure and sludge constructs a complete multi-stage aerobic fermentation process system through steps S1 to S3. The fermentation process of this embodiment organically combines raw material compatibility, multi-parameter coupling control and high-temperature composting to achieve precise control of the fermentation process.

[0093] Example 3

[0094] The similarities with the above embodiments and their combinations will not be repeated, the differences being:

[0095] In the second control phase of step S2, the weighting coefficients and Based on fermentation days Make dynamic adjustments:

[0096] , ;

[0097] in, This represents the total number of days in the fermentation cycle. and The initial influence coefficient, and , When fermentation days Exceeding the total cycle At that time, take , .

[0098] In this embodiment, by constructing weighting coefficients and Depending on the number of fermentation days A dynamically adjusted mathematical model enables adaptive optimization of the synergistic regulation weights of oxygen concentration and pH value during aerobic fermentation. In this embodiment, based on the differences in dominant influencing factors at different stages of the fermentation process, an exponential function is used to allocate the regulation weights over time. It exhibits an exponential decay trend, causing the oxygen concentration regulation weight to gradually decrease as the fermentation process progresses; It exhibits an exponential growth trend, causing the pH control weight to gradually increase as the fermentation process progresses, with the sum of the two always being 1, ensuring a smooth transition of control weight.

[0099] Fermentation days Exceeding the total cycle At that time, take , This indicates that no further dynamic control is needed after the main fermentation cycle ends. In the early stages of aerobic fermentation, microorganisms are in the logarithmic growth phase, exhibiting vigorous metabolic activity and high oxygen consumption rates. Oxygen supply is often a crucial limiting factor for fermentation success, therefore, oxygen concentration control should be dominant. However, as fermentation progresses into the middle and later stages, the material system stabilizes, and the impact of pH on the composting process and nitrogen preservation becomes increasingly prominent, leading to a corresponding increase in the weight of pH control. A study by China Agricultural University, "The Influence of Intermittent Aeration and Manual Turning on the Composting Process," confirmed that oxygen in the compost pile can be rapidly depleted within 27 minutes after turning, indicating the critical importance of timely oxygen supply control in the early stages. Furthermore, as fermentation progresses, pH undergoes a dynamic change from acidic to alkaline, significantly affecting microbial activity and ammonia volatilization; therefore, enhanced pH control is necessary in the later stages. This dynamic weight adjustment strategy avoids the drawbacks of a one-size-fits-all approach with fixed weights throughout the fermentation cycle, achieving adaptive matching between the control strategy and the characteristics of each fermentation stage. It effectively prevents excessive pH control in the early stages from interfering with rapid microbial growth, or excessive oxygen control in the later stages from causing energy waste, thus achieving energy conservation and consumption reduction while ensuring fermentation efficiency. Specific experimental data are shown in Table 3 below:

[0100] Parameter categories Experimental methods / procedures Specific experimental data in conclusion oxygen consumption rate A comparative experiment was conducted using intermittent aeration and manual turning of the pile. A mixture of pig manure and straw was used as raw material, with a C / N ratio adjusted to 25:1, a moisture content of 60%, and a pile volume of approximately 1.5 m³. In the turning group, a portable oxygen meter (probe insertion depth 50 cm) was used immediately after turning to record the oxygen concentration within the pile every 3 minutes for 1 hour. In the intermittent aeration group, a cycle of 15 minutes of aeration followed by 45 minutes of inactivity was used, and the rate of oxygen concentration decrease was monitored using the same method during the inactivity period. After turning the pile, the initial oxygen volume fraction in the pile can reach 18.5%, but it can be depleted to below 2% within 27 minutes; in the intermittent aeration group, the oxygen volume fraction drops from 15.5% to below 2% within 24 minutes after aeration stops. Regardless of the oxygen supply method used in the early stages of fermentation, the oxygen consumption rate is extremely rapid. It is necessary to restore oxygen supply within 30 minutes, otherwise it will easily enter an anaerobic state. pH value change pattern A 40-ton-scale aerobic fermentation experiment was conducted using chicken manure and mushroom residue (C / N = 26:1, moisture content 62%) in a fermentation tank. The fermentation period was 20 days. Nine samples were collected daily from the top, middle, and bottom layers of the fermentation tank. These samples were mixed with deionized water at a 1:10 ratio and shaken. The pH of the extract was measured using a pH meter, and the fermentation temperature was monitored simultaneously. During fermentation, the pH value drops from an initial 7.2 to 5.0-5.3 on days 1-3 (due to organic acid accumulation); on days 4-8, as the temperature rises above 55℃, the pH value rapidly recovers to around 7.0; on days 9-15, with the continued high temperature, the pH value continues to rise to 7.8-8.2; on days 16-20, as the temperature decreases, the pH value stabilizes at around 8.0. The pH value initially decreases and then increases during fermentation, eventually entering a slightly alkaline range, which significantly affects ammonia volatilization and the degree of decomposition. Total fermentation cycle D setting Using pig manure, cow manure, and chicken manure as raw materials, they were mixed with straw (C / N ratio adjusted to 25:1, moisture content 60%). In a 3m³ closed fermentation reactor, the temperature was controlled at 55-65℃. The seed germination index (GI) and ammonium-nitrate ratio of the materials were monitored daily. Maturity was determined by a GI ≥ 70% and a natural temperature decrease. The fermentation cycle for each raw material was then established. The fermentation period for pig manure is 12 days to reach maturity; for cow manure it is 15 days; and for chicken manure it is 18 days. The fermentation cycle varies depending on the raw materials. In this embodiment, the total cycle D is set within the range of 10 to 20 days based on the characteristics of the raw materials and the process requirements. <![CDATA[Initial values of weight coefficients α0 and β0]]> <![CDATA[Using chicken manure and straw as raw materials, an orthogonal experiment on multi-parameter coupled fermentation control was carried out in a 15L laboratory fermentation reactor. The total cycle D was fixed at 15 days, and three groups of controls were set: Group A (α fixed at 0.8, β fixed at 0.2), Group B (α fixed at 0.5, β fixed at 0.5), Group C (α fixed at 0.2, β fixed at 0.8), and Group D (using dynamic adjustment of α0 = 0.8, β0 = 0.2). The cumulative ammonia emissions, organic matter degradation rate, and final seed germination index were monitored daily]]> The final cumulative ammonia emission of Group D under the dynamic adjustment scheme was 12.5 g / kg, lower than Group A (15.8 g / kg), Group B (14.2 g / kg), and Group C (16.1 g / kg); the organic matter degradation rate of Group D was 42.3%, higher than the other groups (Group A 38.7%, Group B 40.1%, Group C 36.5%); the seed germination index of Group D reached 92%, while the other groups were 85%, 88%, and 81%, respectively. <![CDATA[The initial allocation of α0 and β0 is preferably 0.8 and 0.2. Combined with the dynamic adjustment model, it takes into account nitrogen preservation in the later stage while ensuring rapid startup in the early stage, achieving the optimal fermentation effect]]>

[0101] Table 3

[0102] The above experiments show that the dynamic weight adjustment model constructed in this process fully considers the objective laws such as the rapid oxygen consumption rate and significant dynamic changes in pH value during fermentation. Through a time-varying strategy that focuses on oxygen regulation in the early stage and pH regulation in the later stage, it achieves refined and adaptive control of the aerobic fermentation process, providing support for improving fermentation efficiency and ensuring product quality.

[0103] Example 4

[0104] The similarities with the above embodiments and their combinations will not be repeated, the differences being:

[0105] The co-fermentation method of livestock and poultry manure and sludge also includes in-situ passivation of heavy metals and microbial enhancement steps: when the rate of increase of the concentration of free heavy metal ions in the material system in the fermentation reactor exceeds the preset threshold or the concentration exceeds the standard, when the temperature drops to the thermophilic stage of 45~55℃, the microbial enhancement and directional domestication subsystem is activated, and domesticated heavy metal resistant microbial agents and passivation materials are added to the fermentation reactor.

[0106] The heavy metal-resistant microbial agent comprises *Geobacillus stearothermophilus* and *Thermobifida fusca*. The passivation material is modified biochar, prepared by impregnating straw biochar in an iron salt solution, ultrasonically treating it for 30-60 minutes, and then pyrolyzing and activating it at a nitrogen atmosphere at a heating rate of 5-10℃ / min for 30-60 minutes to load nanoscale particles onto its surface. -Fe2O3 particles.

[0107] In this embodiment, the in-situ passivation of heavy metals and the microbial enhancement steps construct a linkage mechanism for the synergistic response of materials and microorganisms to heavy metal stress.

[0108] When the process monitoring module detects that the rate of increase of free heavy metal ion concentration exceeds the preset threshold or the concentration exceeds the standard, the system automatically identifies it as a high-risk state and selects the window period when the temperature drops to the thermophilic stage (45~55℃), which is when the microbial metabolic activity is relatively high and the passivation reaction rate is suitable, to start the microbial enhanced targeted domestication subsystem and simultaneously add domesticated heavy metal resistant microbial agents and modified biochar passivation materials into the fermentation reactor.

[0109] The selected thermophilic bacteria, Geobacillus stearothermophilus and Thermobifida fusca, are both thermophilic functional bacteria in aerobic fermentation systems. The former has been proven to have metabolic regulation capabilities under heavy metal stress, while the latter has application potential in the synergistic effect of cellulose degradation and heavy metal passivation.

[0110] The passivation material is modified biochar, prepared as follows: straw biochar is impregnated in an iron salt solution, ultrasonically treated for 30-60 minutes to achieve uniform iron ion loading, and then pyrolyzed and activated at a nitrogen atmosphere of 300-400℃ with a heating rate of 5-10℃ / min for 30-60 minutes to load nano-sized γ-Fe2O3 particles onto its surface. This process achieves closed-loop control of monitoring, early warning, and response. Through the synergistic effect of functional microorganisms and nano-iron modified materials, the metabolic activity of microorganisms reduces the bioavailability of heavy metals, while the strong adsorption and complexation of γ-Fe2O3 achieves in-situ passivation of heavy metals, effectively inhibiting the risk of heavy metal migration into fermentation products and ensuring the agricultural safety of the product. Relevant experimental data are shown in Table 4 below.

[0111] Parameter categories Experimental methods / procedures Specific experimental data in conclusion Optimization of iron-modified biochar preparation method <![CDATA[Using rice straw as raw material, biochar was prepared by pyrolysis at 500 °C for 2 h. The biochar was impregnated in FeCl3 solution (mass ratio of iron to carbon is 1:10), ultrasonic treated for 30 min, and then dried at 60 °C for 24 h. The dried sample was placed in a tube furnace and pyrolytically activated at different heating rates (3, 5, 8, 10 °C / min) to different temperatures (250, 300, 350, 400, 450 °C) in a nitrogen atmosphere for 30 - 60 min to prepare iron-modified biochar. The materials were characterized by means of XRD, SEM-EDS, BET, etc.]]> <![CDATA[When the activation temperature is 300 - 400 °C and the heating rate is 5 - 10 °C / min, nano-scale γ-Fe2O3 particles are successfully loaded on the surface of the biochar. The particle size is 20 - 50 nm and the distribution is uniform. The specific surface area is increased by 30 - 50% compared with the unmodified biochar. The iron loading is 8 - 12%.]]> <![CDATA[The preparation parameters set in this process (300 - 400 °C, 5 - 10 °C / min, 30 - 60 min) can ensure the successful loading and uniform distribution of γ-Fe2O3, which is the key process window for achieving efficient heavy metal adsorption]]> Adsorption performance of iron-modified biochar for heavy metals Batch adsorption experiments were conducted. 0.1 g of iron-modified biochar was added to 50 mL of a solution containing Cd²⁺ (initial concentration 20 mg / L) or As³⁺ (initial concentration 10 mg / L). The pH was adjusted to 6.5, and the solution was shaken at 25 °C for 24 h. The changes in heavy metal concentrations in the solution before and after adsorption were measured. Iron-modified biochar achieved a Cd²⁺ removal rate of 85.3-94.7% with an adsorption capacity of 8.5-9.5 mg / g; and an As³⁺ removal rate of 76.8-88.2% with an adsorption capacity of 3.8-4.4 mg / g. Compared with unmodified biochar, the Cd²⁺ removal rate was increased by 35-50%, and the As³⁺ removal rate was increased by 40-60%. <![CDATA[Iron-modified biochar has excellent adsorption capacity for both Cd and As. The loading of γ-Fe2O3 significantly enhances the affinity for heavy metals and can effectively reduce the concentration of free heavy metals in the fermentation system]]> Iron-modified biochar passivation efficiency of Cd Soil incubation experiment: Cd-contaminated soil (total Cd content 2.5 mg / kg) was used as the research object. 3% (mass fraction) of iron-modified biochar was added, and the soil was incubated for 30 days at 25℃ and 60% field capacity. The changes in the content of available Cd were determined using the DTPA extraction method. After 30 days of cultivation, the treatment with iron-modified biochar based on dead leaves reduced the available Cd content in the soil by 70.0% compared to the control; the treatment with iron-modified biochar based on rice straw reduced it by 58.3%; and the treatment with iron-modified biochar based on pig manure reduced it by 45.6%. Iron-modified biochar exhibits a significant passivation effect on Cd, which can substantially reduce the bioavailability of heavy metals. Iron-modified biochar passivation efficiency of As <![CDATA[Soil incubation experiment: Taking As-contaminated soil (total As content 45.58 mg / kg) as the object, adding 3% iron-modified biochar, incubating at 25 °C for 30 days, and using the NaH2PO4 extraction method to determine the change in available As content]]> After 30 days of cultivation, iron-modified biochar treatment reduced the content of available As in the soil by 22.20-40.26%; among them, iron-modified biochar prepared by co-precipitation method showed better passivation effect on As than materials prepared by impregnation pyrolysis method. Iron-modified biochar also has a passivation effect on As, reducing the migration and bioavailability of As, thus achieving synergistic passivation of Cd-As complex pollution. Thermophilic fat-loving Bacillus heavy metal tolerance <![CDATA[Using the medium gradient domestication method, gradually increase the Cd²⁺ concentration (0, 5, 10, 20, 50, 100 mg / L) in the basal medium, inoculate Geobacillus stearothermophilus, culture at 55 °C for 24 h, and measure the OD 600 value to evaluate the growth status of the strain]]> <![CDATA[The strain grew well when the Cd²⁺ concentration was ≤ 50 mg / L (OD 600 ≥ 0.8); when the Cd²⁺ concentration reached 100 mg / L, the growth was significantly inhibited (OD 600 ≤ 0.3); after 5 generations of gradient acclimation, the OD of the strain at a Cd²⁺ concentration of 100 mg / L 600 was increased to above 0.6]]> Bacillus thermophilus exhibits a certain degree of tolerance to heavy metals, and its tolerance can be further enhanced through targeted domestication, making it suitable for fermentation enhancement in environments contaminated with heavy metals. Heavy metal tolerance of brown thermophilic spores The plate culture method was used. *Thermobifida fusca* was inoculated onto solid culture media containing different concentrations of Cd²⁺ (0, 10, 20, 50 mg / L) and incubated at 50°C for 48 h. Colony diameters were then measured. At a Cd²⁺ concentration of 10 mg / L, the colony diameter was 85% of the control group; at 20 mg / L, it was 62% of the control group; and at 50 mg / L, growth was almost completely inhibited (colon diameter <2 mm). Thermophilic spp. is sensitive to heavy metals and requires acclimatization before it can be used for enhanced remediation of systems contaminated with high concentrations of heavy metals. Synergistic passivation effect of microorganisms and modified biochar Simulated fermentation system experiment: A control group (heavy metals only), a modified biochar group (3% iron-modified biochar), a microbial group (acclimated bacterial agent added), and a synergistic group (modified biochar and bacterial agent added simultaneously) were set up. The initial Cd²⁺ concentration was 50 mg / L. The system was cultured at 55℃ and pH 7.5 with shaking for 7 days, and the change in the concentration of free Cd²⁺ in the solution was measured. After 7 days of cultivation, the Cd²⁺ concentration was 48.2 mg / L in the control group; 15.6 mg / L in the modified biochar group (removal rate 67.6%); 32.4 mg / L in the microbial group (removal rate 32.8%); and 8.7 mg / L in the synergistic group (removal rate 82.5%). There is a synergistic effect between microorganisms and modified biochar; the combined use of the two can significantly improve the passivation efficiency of heavy metals, which is superior to the effect of using either method alone.

[0112] Table 4

[0113] Example 5

[0114] The similarities with the above embodiments and their combinations will not be repeated, the differences being:

[0115] The co-fermentation method of livestock and poultry manure and sludge also includes a step of exhaust gas treatment and leachate co-management: the exhaust gas generated during the fermentation process is collected and passed into a spray tower containing leachate or clean water for washing to remove malodorous gases; the circulating liquid of the spray tower is discharged periodically, and after the water quality is tested, the central controller decides, based on the real-time moisture content and carbon-nitrogen ratio of the material in the fermentation reactor and the conductivity of the recycled liquid, to return all or part of the liquid after solid-liquid separation to the mixing and blending unit to replace part of the clean water; when the EC value of the recycled liquid exceeds the crop tolerance threshold, the remaining part is discharged into the sewage treatment system.

[0116] In this embodiment, a closed-loop resource utilization system with gas-liquid coupling is constructed through the above-described tail gas treatment and leachate co-management steps. The tail gas containing odorous components such as ammonia and hydrogen sulfide generated during fermentation is collected and fed into a spray tower. Leachate or water is used as the absorbent for gas-liquid contact washing. The spray tower acts as a mass transfer device, allowing odorous substances in the gas phase to be transferred to the liquid phase through dissolution, absorption, or chemical reaction. Commonly used chemical absorbents such as sodium hydroxide solution can effectively remove acidic odorous gases such as hydrogen sulfide.

[0117] After the circulating liquid from the spray tower is periodically discharged, it undergoes solid-liquid separation treatment. The central controller makes reuse decisions based on real-time data from three dimensions: First, the real-time moisture content of the material in the fermentation reactor to determine whether water needs to be added; second, the real-time carbon-to-nitrogen ratio of the material to determine whether the organic matter brought in by the reused liquid is beneficial to carbon-to-nitrogen balance; and third, the electrical conductivity (EC) value of the reused liquid to assess whether its salt content exceeds the crop's tolerance threshold (generally, an EC value exceeding 1-3 mS / cm may inhibit seed germination or crop growth). When the EC value is within a safe range and the moisture content or carbon-to-nitrogen ratio needs adjustment, part or all of the reused liquid is returned to the mixing and blending unit to replace clean water; when the EC value exceeds the standard, it is discharged into the wastewater treatment system for advanced treatment.

[0118] The process in this embodiment realizes the resource recycling of waste treatment. By using leachate as a spray absorption medium, it not only saves the amount of clean water, but also removes some of the volatile organic compounds in the leachate through tail gas washing. At the same time, the washing liquid is recycled for the batching process, forming a material closed loop, which significantly reduces the amount of wastewater discharged from the system and the amount of fresh water consumed.

[0119] It should be noted that, in actual implementation, the structure described in this specification is not a fixed or unchanging embodiment. The components of the embodiments of the present invention described and shown herein can be arranged and designed in various different configurations. These are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Furthermore, this specification is for illustrative purposes only and does not represent the specific structure or actual quantity in a concrete implementation.

[0120] Unless otherwise defined, the technical or scientific terms used herein should be understood in their ordinary sense as would be understood by one of ordinary skill in the art to which this invention pertains. The use of terms such as "a" or "an" in this specification and claims does not necessarily indicate a limitation of quantity. Terms such as "comprising" or "including" mean that the element or component preceding the word encompasses the element or component listed following the word and its equivalents, without excluding other elements or components. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

[0121] The exemplary embodiments of the present invention have been described in detail above with reference to preferred embodiments. The experimental data disclosed are experimental data of parameter values ​​near the preferred parameters. Experimental data of parameter values ​​that are too much or too little beyond the optimized parameters have relatively low reference value and will not be described in detail here.

[0122] However, those skilled in the art will understand that various modifications and alterations can be made to the above specific embodiments without departing from the concept of the present invention, and various combinations can be made to the various technical features and structures proposed in the present invention without exceeding the protection scope of the present invention.

Claims

1. A control system for the co-fermentation of livestock and poultry manure and sludge, characterized in that, include: The raw material pretreatment unit is used to receive and test the input livestock and poultry manure and sludge, and obtain their physicochemical property parameters; A mixing and blending unit, which is connected to the raw material pretreatment unit, is used to generate a mixed substrate by adjusting the mass mixing ratio of feces and sludge based on a target carbon-nitrogen ratio range. A fermentation reactor, equipped with temperature control, stirring and aeration devices, is used to receive the mixed substrate and carry out aerobic fermentation; The process monitoring and control module includes a temperature sensor, a pH sensor, an oxygen concentration sensor, an online near-infrared spectrometer, and a heavy metal monitoring module installed in the fermentation reactor, which are used to monitor fermentation process parameters in real time. A microbial enhancement and acclimatization subsystem is connected to the fermentation reactor for enriching and / or acclimatizing functional microorganisms and for returning the acclimatized microorganisms to the fermentation reactor. The leachate collection and treatment unit is used to collect the leachate generated at the bottom of the fermentation reactor and, based on its water quality test results, to partially or wholly reuse it in the mixing and blending unit to adjust the moisture content of the materials, or to transport it to the wastewater treatment system. The central controller is electrically connected to each of the aforementioned units and modules. The central controller is configured to execute fermentation control logic containing multi-parameter coupling and condition judgment to trigger the microbial enhanced directional domestication subsystem based on real-time data from the process monitoring and control module, so as to coordinately regulate the fermentation process.

2. The control system for the co-fermentation of livestock and poultry manure and sludge according to claim 1, characterized in that, The process monitoring and control module includes a temperature sensor, a pH sensor, an oxygen concentration sensor, an online near-infrared spectrometer, and a heavy metal monitoring module. The central controller uses the effective carbon-nitrogen ratio of the mixed substrate predicted in real time by the online near-infrared spectrometer. ,when With the set target value When the deviation exceeds a preset threshold, the mixing and blending unit or the auxiliary material addition device is controlled to automatically adjust the carbon-nitrogen ratio.

3. The control system for the co-fermentation of livestock and poultry manure and sludge according to claim 1 or 2, characterized in that, The microbial enhanced acclimatization subsystem includes a bypass acclimatization reactor, which gradually increases the concentration of heavy metal ions in the culture medium through a batch fed-batch culture method over a time series, for the targeted screening and expansion of thermophilic microbial agents with heavy metal tolerance.

4. A method for co-fermenting livestock and poultry manure and sludge using the co-fermentation control system for livestock and poultry manure and sludge according to any one of claims 1 to 3, characterized in that, Includes the following steps: Step S1, Raw Material Analysis and Compatibility: The physicochemical properties of livestock and poultry manure and sludge are tested. The mixing ratio is calculated based on the carbon-nitrogen ratio balance principle, and the mixture is then thoroughly mixed according to the calculated ratio. The target carbon-nitrogen ratio... The range is 22~28; Step S2, Multi-parameter coupled fermentation control: In the first control stage, the ventilation volume is adjusted based on the temperature deviation using a ventilation volume control model; in the second control stage, the stirring rate is synergistically regulated based on oxygen concentration and pH value. Step S3, aging, composting and post-processing: Maintain the fermentation temperature within the range of 55~65℃ for high-temperature composting and maintain it for no less than 5 days. When the preset composting degree judgment conditions are met, the fermentation is terminated, and the discharged material is transferred to the aging area for secondary aging. The aged material is processed into organic fertilizer products through screening and crushing processes.

5. The method for co-fermentation of livestock and poultry manure and sludge according to claim 4, characterized in that, In step S2: The ventilation volume control model for the first control stage is as follows: ； in, Ventilation volume; The target temperature is defined as 55~65℃. This is the measured temperature; The base ventilation rate is taken as 0.05~0.15 m³ / (h·m³ of material); For material volume; This is a proportionality coefficient, with a value ranging from 0.05 to 0.15 m³. The stirring rate control model for the second control stage is as follows: ； in, This refers to the stirring rate; Based on the stirring rate; and These are dimensionless weighting coefficients; To set the oxygen concentration, the value range is 8% to 18%; For actual measurement of oxygen concentration; The optimal pH value is between 7.5 and 8.

5. The allowable pH fluctuation bandwidth is defined as 0.3 to 0.

8.

6. The method for co-fermentation of livestock and poultry manure and sludge according to claim 5, characterized in that, Weighting coefficients in the second control phase and Based on fermentation days Make dynamic adjustments: ， ； in, This represents the total number of days in the fermentation cycle. and The initial influence coefficient, and , When fermentation days Exceeding the total cycle At that time, take , .

7. The method for co-fermentation of livestock and poultry manure and sludge according to claim 4, characterized in that, It also includes in-situ passivation of heavy metals and microbial enhancement steps: when the rate of increase of the concentration of free heavy metal ions in the material system in the fermentation reactor exceeds the preset threshold or the concentration exceeds the standard, when the temperature drops to the thermophilic stage of 45~55℃, the microbial enhancement and directional domestication subsystem is activated, and domesticated heavy metal resistant microbial agents and passivation materials are added to the fermentation reactor.

8. The method for co-fermentation of livestock and poultry manure and sludge according to claim 7, characterized in that, The heavy metal resistant microbial agent contains *Bacillus stearothermophilus* and *Schizosporium brownii*. The passivation material is modified biochar, and its preparation method includes: impregnating straw biochar in an iron salt solution, ultrasonically treating it for 30-60 minutes, and then pyrolyzing and activating it at a heating rate of 5-10℃ / min under a nitrogen atmosphere at 300-400℃ for 30-60 minutes, so that its surface is loaded with nanoscale... -Fe2O3 particles.

9. The method for co-fermentation of livestock and poultry manure and sludge according to claim 4, characterized in that, In step S1, the carbon-nitrogen ratio balance principle is calculated based on the measured fecal carbon content. Nitrogen content With sludge carbon content Nitrogen content Calculate the fecal mass fraction using the following formula. : ； in, , , , Expressed as a percentage of mass, with a non-zero denominator; the solution... The value is used as the initial blending ratio; when adding auxiliary materials, the carbon and nitrogen contributions of the auxiliary materials are incorporated into the above equation for recalculation.

10. The method for co-fermentation of livestock and poultry manure and sludge according to claim 4, characterized in that, It also includes a step of co-management of exhaust gas treatment and leachate: the exhaust gas generated during fermentation is collected and then passed into a spray tower containing leachate or clean water for washing to remove malodorous gases. The circulating liquid from the spray tower is discharged periodically. After the water quality is tested, the central controller decides whether to return all or part of the liquid after solid-liquid separation to the mixing and blending unit to replace part of the clean water based on the real-time moisture content and carbon-nitrogen ratio of the material in the fermentation reactor and the conductivity of the recycled liquid. When the EC value of the recycled liquid exceeds the crop tolerance threshold, the remaining part is discharged into the sewage treatment system.

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