An eco-planting environment-friendly soil modifier preparation system

Abstract

The application discloses an environment-friendly soil modifier preparation system for ecological planting, and relates to the technical field of solid waste resource utilization.The system comprises a feeding dynamic formula regulation and control subsystem, a toxic by-product source inhibition subsystem, a maturation and composting end point decision subsystem and a central edge calculation control unit.The central edge calculation control unit analyzes the carbon-nitrogen ratio and moisture content of the material according to the detection signals of a near-infrared spectrum probe and a dielectric moisture sensing array, adjusts the discharging rate of a variable frequency feeder, triggers zoned steam injection and oxygen supply adjustment according to the polycyclic aromatic hydrocarbon precursor concentration signal detected by a gas phase sensing array, calculates a comprehensive composting index according to the signals of an electronic nose module and a carbon dioxide concentration sensor, and controls the opening of a discharging valve.The application realizes integrated closed-loop control of raw material sensing, by-product inhibition and composting decision, and improves the product quality stability and safety.

Description

Technical Field

[0001] This invention relates to the field of solid waste resource utilization technology, specifically to a system for preparing an environmentally friendly soil conditioner for ecological planting. Background Technology

[0002] Soil conditioners for ecological planting are usually made from organic waste such as livestock and poultry manure and crop straw. They are prepared through processes such as raw material pretreatment, fermentation or pyrolysis reaction and finished product maturation. In the raw material pretreatment stage, materials from different sources with large fluctuations in composition need to be adjusted to the appropriate carbon-nitrogen ratio range and moisture content range for fermentation or pyrolysis.

[0003] The core reaction process involves controlling parameters such as temperature and oxygen supply to achieve the biodegradation or pyrolysis transformation of materials.

[0004] In the finished product maturation process, the material is continuously ventilated and turned over to stabilize it before being discharged.

[0005] The closest prior art to this invention is a complete set of equipment for preparing soil conditioner from organic waste. Its structure includes a raw material silo, a crushing and mixing device, a fermentation or pyrolysis reaction chamber, a maturation chamber, and a discharge device. The devices are connected in sequence by conveyor belts. The equipment works as follows: the operator puts the raw materials into the crushing and mixing device for crushing and preliminary mixing according to a pre-set fixed ratio, and then sends them into the reaction chamber for fermentation or pyrolysis treatment via the conveyor device.

[0006] After the reaction is complete, the material enters the maturation chamber. After a preset fixed fermentation cycle or after reaching a certain cumulative number of days, the discharge valve is opened manually or according to the time sequence controller to complete the unloading.

[0007] The aforementioned existing technologies do not have the ability to detect the moisture content and carbon-nitrogen ratio of raw materials online, and the proportioning relies on fixed empirical parameters;

[0008] There is also a lack of online monitoring methods for the formation of toxic byproducts such as polycyclic aromatic hydrocarbons and persistent environmental free radicals during the reaction process. Unqualified products can only be eliminated by post-production sampling inspection.

[0009] Furthermore, its discharge determination relies on empirical standards such as fixed fermentation cycles or single temperature thresholds, without directly measuring the true biological stability of the material. These defects lead to problems such as imbalanced ratios, insufficient ability to suppress toxic byproducts at the source, and batch-to-batch product quality fluctuations when this existing technology is used to treat multi-source heterogeneous organic waste, which need to be further improved. Summary of the Invention

[0010] The technical problem to be solved by this invention is:

[0011] Existing soil conditioner preparation systems for ecological planting lack the ability to dynamically sense raw material components and adaptively adjust formulations when treating multi-source heterogeneous organic wastes such as livestock and poultry manure and crop straw, leading to imbalances in the formulation.

[0012] Meanwhile, existing preparation equipment lacks online monitoring and source suppression methods for the formation of toxic byproducts such as polycyclic aromatic hydrocarbons and environmentally persistent free radicals during composting or pyrolysis processes.

[0013] In addition, the existing system's discharge determination relies on rigid standards such as fixed fermentation cycles or single temperature thresholds, which cannot reflect the true biological stability of the material, resulting in large fluctuations in product quality between batches, and even the risk of seedling burn caused by applying unfermented amendments to farmland.

[0014] To solve the above-mentioned technical problems, the present invention provides an environmentally friendly soil conditioner preparation system for ecological planting, including a feeding and mixing device, a core thermal reaction chamber and a maturation chamber connected in sequence by a material conveying channel, and also includes a feeding dynamic formula control subsystem, a toxic by-product source inhibition subsystem, a maturation and decomposition endpoint decision subsystem and a central edge computing control unit.

[0015] The feed dynamic formulation control subsystem includes a near-infrared spectral probe installed above the material conveyor belt at the outlet of the feed mixing device, a dielectric moisture sensor array installed below the material conveyor belt, and a biochar frequency converter and a composting agent frequency converter for adding auxiliary materials to the material flow, respectively. The central edge computing control unit analyzes the carbon-nitrogen ratio and moisture content of the material and dynamically adjusts the feeding rate of the two frequency converters, forming a physical closed loop of online sensing of raw material components and automatic formulation correction.

[0016] The toxic byproduct source suppression subsystem includes an online sensor array for gaseous volatile organic compounds and polycyclic aromatic hydrocarbons installed in the exhaust channel of the core thermal reaction chamber, a group of superheated steam nozzles arranged in sections along the length of the core thermal reaction chamber, a group of pneumatic solenoid valves connected one-to-one with the superheated steam nozzles via steam pipelines, and an oxygen supply regulating damper for adjusting the oxygen supply to each section. By triggering independent steam injection and oxygen supply linkage regulation in each section through a concentration threshold, the system achieves in-situ blocking of the precursors of toxic byproducts during the process.

[0017] The maturation and composting endpoint decision subsystem includes an electronic nose module installed at the exhaust end of the maturation chamber, a carbon dioxide concentration sensor, and a maturation chamber unloading valve controlled by the subsystem. By weighted fusion of multidimensional gas signals and dynamic respiration index signals, combined with dual verification of continuous holding time, the subsystem enables intelligent determination of the true biological stability of the modifier.

[0018] Compared with the prior art, the beneficial effects of the present invention by adopting the above technical solution are as follows:

[0019] 1. This invention ensures that the carbon-nitrogen ratio and moisture content of each batch of materials entering the reaction section are within the preset target range, thus avoiding fermentation abnormalities caused by raw material fluctuations;

[0020] 2. This invention suppresses free radical polymerization chain reaction in real time at the source stage of the reaction. Pilot-scale testing has verified that after triggering superheated steam injection and oxygen supply adjustment, the concentration of polycyclic aromatic hydrocarbon precursors in the exhaust gas of the corresponding temperature zone of the reaction chamber can drop from above the warning threshold to below the warning threshold, achieving a source suppression effect, reducing the generation of polycyclic aromatic hydrocarbons and environmentally persistent free radicals, and improving the environmental safety of the produced modifier.

[0021] 3. This invention eliminates batch-to-batch quality fluctuations through multi-dimensional signal fusion and dual verification of duration, avoiding the risk of secondary fermentation and seedling burn caused by applying uncomposted amendments to ecological soil. Attached Figure Description

[0022] Figure 1 This is an overall architecture diagram of the system in an embodiment of the present invention;

[0023] Figure 2 This is a control flowchart of the dynamic feed formulation control subsystem in an embodiment of the present invention;

[0024] Figure 3 This is a control flowchart of the ripening and fermentation endpoint decision subsystem in an embodiment of the present invention. Detailed Implementation

[0025] The following is in conjunction with the appendix Figure 1-3 The specific embodiments of the present invention will be further described below. It should be noted that the description of these embodiments is for the purpose of helping to understand the present invention, but does not constitute a limitation of the present invention.

[0026] The environmentally friendly soil conditioner preparation system for ecological planting provided by this invention includes, in its overall structure, a raw material silo, a crushing and mixing device, a core thermal reaction chamber, and a maturation chamber connected in sequence by a material conveying channel. On this basis, it integrates a dynamic formula control subsystem for feeding, a source inhibition subsystem for toxic byproducts, a maturity and decomposition endpoint decision subsystem, and a central edge computing control unit that coordinates the three. Each subsystem interacts with the central edge computing control unit through a unified data bus to form a complete closed-loop control system.

[0027] I. Feed Dynamic Formulation Control Subsystem

[0028] The subsystem consists of: a near-infrared spectral probe installed above the material conveyor belt at the discharge port of the crushing and mixing device; a dielectric moisture sensing array installed below the material conveyor belt; an edge computing gateway electrically connected to the sensors; and a biochar frequency converter and a composting agent frequency converter electrically connected to the edge computing gateway. The near-infrared spectral probe is used to collect the absorption spectral signal of the material surface in the near-infrared band (900 nm to 1700 nm) in real time.

[0029] Dielectric moisture sensor arrays are used to collect the dielectric constant signal of materials in real time and convert it into a moisture content value.

[0030] The edge computing gateway has a built-in partial least squares regression analytical model trained based on historical calibration samples, which is used to resolve spectral signals and dielectric signals into the carbon content, nitrogen content and moisture content of the material.

[0031] Specifically, the near-infrared spectral probe uses a fixed sampling period Collect the absorbance spectral signal of the current batch of materials, and record it as... ,in Indicates wavelength variable, Indicates the current sampling time;

[0032] A dielectric moisture sensor array synchronously acquires the dielectric response signal of the material. The edge computing gateway calls a pre-established partial least squares analytical model to analyze the absorbance spectral signal and dielectric response signal into the carbon content of the material. Nitrogen content and moisture content And calculate the real-time carbon-nitrogen ratio of the current batch of materials:

[0033] ;

[0034] in, express The carbon content of the material obtained from real-time analysis is expressed as a percentage by mass on a dry basis.

[0035] express The nitrogen content of the material obtained from real-time analysis is expressed as a percentage by mass on a dry basis.

[0036] express The carbon-nitrogen ratio of the material at any given time.

[0037] Then calculate the carbon-nitrogen ratio deviation. and moisture content deviation :

[0038] ;

[0039] ;

[0040] in, This indicates the system's preset target carbon-to-nitrogen ratio. This indicates the system's preset target moisture content.

[0041] Based on the aforementioned deviation values, the edge computing gateway employs a proportional-integral-derivative feedback control strategy to dynamically calculate the target feeding rate of the biochar variable frequency feeder.

[0042] ;

[0043] in, express The feed rate setting of the variable frequency feeder for biochar is expressed in kilograms per hour.

[0044] , , These represent the proportional, integral, and derivative control coefficients, which are determined through on-site debugging and tuning.

[0045] This represents the system sampling period. The edge computing gateway uses the same control strategy as the above formula, based on the moisture content deviation. Calculate the target feeding rate of the frequency converter feeder and its matching water replenishment device for composting microbial agents. The calculation method is similar to the above formula, except that the carbon-nitrogen ratio related variable is replaced with the moisture content related variable and the corresponding control coefficient. The edge computing gateway converts the calculated target rate value into control commands and sends them to the frequency converters of the biochar frequency converter and the composting agent frequency converter, respectively, to adjust their feeding rate in real time, and according to the sampling period. Continuous online monitoring and dynamic correction are carried out until the batch of materials is fully mixed and enters the next reaction process.

[0046] As an alternative implementation, the material moisture detection sensor and component detection sensor in this subsystem can also be a combination of a microwave resonant moisture detection sensor and a near-infrared combined with a mid-infrared dual-band spectral detection device. By fusing and analyzing the carbon-nitrogen ratio of the material through dual-band spectral data, the remaining control logic remains unchanged, and the same technical effect of online sensing of raw material components and dynamic closed-loop control of the formula can be achieved.

[0047] II. Toxic Byproduct Source Suppression Subsystem

[0048] The subsystem comprises: an online sensor array for gaseous volatile organic compounds and polycyclic aromatic hydrocarbons (using a combination of photoionization detection principle sensors and electrochemical sensors) installed in the exhaust channel at the top of the core thermal reaction chamber; a group of superheated steam nozzles arranged in sections along the length of the reaction chamber; a group of pneumatic solenoid valves connected to the steam nozzle groups; oxygen supply regulating dampers for adjusting the oxygen supply in each temperature zone; and a central edge computing control unit electrically connected to the aforementioned sensor array and actuators.

[0049] The gas phase sensor array acquires the concentration signals of polycyclic aromatic hydrocarbon precursors in the exhaust channels of each temperature zone of the reaction chamber in real time at a fixed sampling period, denoted as The central edge computing control unit calculates the rate of change of the current concentration relative to the previous sampling time:

[0050] ;

[0051] Will With the preset warning threshold and safety threshold ( Less than ) for comparison, when Not less than If the temperature zone is deemed to have a risk of abnormal polycyclic aromatic hydrocarbon (PAH) formation, calculate the incremental superheated steam flow rate that should be injected into the temperature zone:

[0052] ;

[0053] in, express The increment of superheated steam flow rate that should be injected into this temperature zone at any time, in kilograms per hour;

[0054] Indicates the steam injection ratio coefficient;

[0055] This represents the steam injection rate coefficient, both of which were determined through prior experimental calibration. The central edge computing control unit will... The command is converted into the opening control command of the corresponding temperature zone pneumatic solenoid valve and executed. At the same time, the opening of the oxygen supply regulating damper in that temperature zone is reduced to create a local low-oxygen, water vapor-rich atmosphere to inhibit the occurrence of free radical polymerization chain reaction. The change trend of polycyclic aromatic hydrocarbon precursor concentration in that temperature zone after the execution action is continuously monitored. If the concentration has fallen back to below the warning threshold, the steam solenoid valve is gradually closed and the normal oxygen supply gradient is restored.

[0056] If the concentration continues to rise and approaches the safety threshold, the steam injection volume will be further increased and the system alarm will be triggered. The above monitoring and blocking process is executed independently for each temperature zone of the reaction chamber, so as to achieve a source suppression effect of multi-temperature zone synergy.

[0057] As an alternative implementation, the subsystem may not use the pneumatic blocking method of superheated steam injection combined with oxygen supply regulating damper, but instead use the method of locally injecting inert gas into the abnormal temperature zone and cooperating with a rapid cooling device to suppress the free radical polymerization chain reaction by reducing the local oxygen concentration and reaction temperature. Its triggering conditions and control logic for independent execution of zones are the same as those described above.

[0058] III. Maturation and Decomposition Endpoint Decision Subsystem

[0059] The subsystem comprises: an electronic nose module (containing gas-sensitive sensing units for ammonia, hydrogen sulfide, and volatile fatty acids) installed at the exhaust end of the finished product curing silo; a carbon dioxide concentration sensor installed at the same exhaust end; a computing unit for calculating the dynamic respiratory index based on the carbon dioxide release rate; a central edge computing control unit electrically connected to the aforementioned sensing units; and a curing silo unloading valve controlled by the unit.

[0060] The electronic nose module collects sensor response signals for ammonia, hydrogen sulfide, and volatile fatty acids in the exhaust gas from the curing chamber in real time at a fixed sampling period, denoted as follows: , , ;

[0061] A carbon dioxide concentration sensor synchronously collects the carbon dioxide concentration signal in the exhaust gas, and the processing unit calculates the dynamic respiration index of the material based on this signal, denoted as... The central edge computing control unit normalizes the above four indicators respectively:

[0062] ;

[0063] in, Indicates the first Item In The original measurement value at time, These correspond to one of the following values: ammonia response value, hydrogen sulfide response value, volatile fatty acid response value, or dynamic respiratory index value.

[0064] and These represent the lower and upper limits of the indicator within the system's calibration range, respectively.

[0065] This represents the normalized index value, ranging from 0 to 1.

[0066] The central edge computing control unit uses a weighted fusion method to calculate the comprehensive maturity index:

[0067] ;

[0068] in, express The overall maturity index at any given moment;

[0069] , , , These represent the weighting coefficients for the four indicators: ammonia, hydrogen sulfide, volatile fatty acids, and dynamic respiration index. The sum of these four coefficients is 1, and each weighting coefficient is determined through training and calibration using historical decomposition batch data.

[0070] The comprehensive maturity index Compared with the preset maturity determination threshold When comparing, Not greater than Meanwhile, the central edge computing control unit continuously counts the consecutive durations during which the judgment condition is met. ;

[0071] when Not less than the preset stable holding time At that time, it was determined that the batch of amendment had reached the true biological stabilization state, and an opening command was issued to the unloading valve of the maturation chamber to complete the automatic unloading;

[0072] If fluctuations occur after the judgment condition is met, leading to... Less than If the timing fails, the timer will restart to avoid misjudgment caused by instantaneous fluctuations.

[0073] In summary, this invention achieves integrated closed-loop control through the coordinated operation of three functional subsystems and a central edge computing control unit, enabling online raw material sensing, closed-loop formula regulation, in-situ inhibition of toxic byproducts, and intelligent decision-making at the maturity endpoint. Those skilled in the art can adapt the sensor models, control coefficients, and threshold parameters to actual production needs based on the above-described embodiments, all of which fall within the scope of this invention.

[0074] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, any modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope defined by the claims of the present invention.

Claims

1. A system for preparing an environmentally friendly soil conditioner for ecological planting, comprising a feeding and mixing device, a core thermal reaction chamber, and a maturation chamber connected in sequence by a material conveying channel, characterized in that, Also includes: The feed dynamic formulation control subsystem includes a near-infrared spectral probe installed above the material conveyor belt at the outlet of the feed mixing device, a dielectric moisture sensor array installed below the material conveyor belt, and a biochar frequency converter and a composting agent frequency converter for adding auxiliary materials to the material flow, respectively. The toxic byproduct source suppression subsystem includes an online sensor array for gaseous volatile organic compounds and polycyclic aromatic hydrocarbons installed in the exhaust channel of the core thermal reaction chamber, a superheated steam nozzle group arranged in sections along the length of the core thermal reaction chamber, a pneumatic solenoid valve group connected to the superheated steam nozzle group one by one through steam pipelines, and an oxygen supply regulating damper for adjusting the oxygen supply of each section. The maturation and ripening endpoint decision subsystem includes an electronic nose module installed at the exhaust end of the maturation chamber, a carbon dioxide concentration sensor installed at the exhaust end of the maturation chamber, and a maturation chamber unloading valve controlled by the subsystem. The central edge computing control unit is electrically connected to the near-infrared spectral probe, the dielectric moisture sensing array, the gaseous volatile organic compounds and polycyclic aromatic hydrocarbons online sensing array, the electronic nose module, and the carbon dioxide concentration sensor, respectively, for receiving detection signals and performing analysis and calculation. It is also electrically connected to the biochar frequency converter, the composting agent frequency converter, the pneumatic solenoid valve group, the oxygen supply regulating damper, and the composting silo unloading valve, respectively, for issuing control commands based on the analysis and calculation results. The central edge computing control unit analyzes the carbon-nitrogen ratio and moisture content of the material based on the absorbance spectral signal collected by the near-infrared spectral probe and the dielectric response signal collected by the dielectric moisture sensing array, and adjusts the feeding rate of the biochar frequency converter and the composting agent frequency converter according to the carbon-nitrogen ratio deviation and moisture content deviation, respectively. The central edge computing control unit, based on the concentration signal of polycyclic aromatic hydrocarbon precursors collected by the online sensor array of gaseous volatile organic compounds and polycyclic aromatic hydrocarbons, controls the opening of the pneumatic solenoid valve group of the corresponding partition to inject superheated steam into the partition when the concentration signal is not less than a preset warning threshold, and also reduces the opening of the oxygen supply regulating damper of the partition. The central edge computing control unit weighted and fused the response signals of ammonia, hydrogen sulfide and volatile fatty acid sensors collected by the electronic nose module with the dynamic respiration index calculated based on the signal collected by the carbon dioxide concentration sensor to obtain a comprehensive maturation index. When the comprehensive maturation index is not greater than the preset maturation judgment threshold and the duration is not less than the preset stable holding time, the control unit opens the unloading valve of the maturation chamber.

2. The system according to claim 1, characterized in that, The central edge computing control unit uses a proportional-integral-derivative feedback control strategy to calculate the feed rate correction of the biochar frequency converter. The feed rate correction is calculated by weighting the proportional term, the cumulative term, and the rate of change term of the carbon-nitrogen ratio deviation at the current moment. The central edge computing control unit also uses a proportional-integral-derivative feedback control strategy to calculate the feeding rate correction of the frequency conversion feeder for the composting agent. The feeding rate correction is calculated by weighting the proportional term, the cumulative term, and the rate of change term of the moisture content deviation at the current moment.

3. The system according to claim 1, characterized in that, The central edge computing control unit is preset with an early warning threshold and a security threshold, wherein the security threshold is greater than the early warning threshold; When the concentration signal of the polycyclic aromatic hydrocarbon precursor is not less than the warning threshold, the central edge computing control unit calculates the superheated steam flow increment based on the deviation of the concentration signal from the warning threshold and the rate of change of the concentration signal from the previous sampling time, and controls the opening degree of the pneumatic solenoid valve assembly accordingly.

4. The system according to claim 1, characterized in that, The core thermal reaction chamber is divided into multiple temperature zones along its length. Each temperature zone is equipped with an independent online sensor array for gaseous volatile organic compounds and polycyclic aromatic hydrocarbons, a superheated steam nozzle group, a pneumatic solenoid valve group, and an oxygen supply regulating damper. The central edge computing control unit independently monitors and controls each temperature zone.

5. The system according to claim 1, characterized in that, The electronic nose module includes gas-sensitive sensing units for ammonia, hydrogen sulfide, and volatile fatty acids, respectively. The central edge computing control unit normalizes the response signals from the ammonia sensor, hydrogen sulfide sensor, volatile fatty acid sensor, and dynamic respiration index, and then weights and fuses them to obtain the comprehensive decomposition index. The sum of the weight coefficients corresponding to the four indicators is 1.

6. The system according to claim 5, characterized in that, When the comprehensive maturity index is not greater than the preset maturity judgment threshold for a period of time that the central edge computing control unit determines that the batch of modifier has reached the biological stabilization state, and issues an opening command to the unloading valve of the maturity chamber. If the state where the comprehensive maturity index is not greater than the maturity determination threshold is interrupted before the duration of the stable maintenance period is reached, the timer is restarted.

7. A method for preparing an environmentally friendly soil conditioner for ecological planting, implemented using the system described in claim 1, characterized in that, include: The absorbance spectrum signal of the material in the near-infrared band was collected using a near-infrared spectral probe, and the dielectric response signal of the material was collected using a dielectric moisture sensor array. The carbon-nitrogen ratio and moisture content of the material were then analyzed. Adjust the feeding rate of the biochar variable frequency feeder according to the carbon-nitrogen ratio deviation, and adjust the feeding rate of the composting agent variable frequency feeder according to the moisture content deviation. The concentration signal of polycyclic aromatic hydrocarbon precursors in the core thermal reaction chamber is collected by an online sensor array of gaseous volatile organic compounds and polycyclic aromatic hydrocarbons. When the concentration signal is not less than the preset warning threshold, superheated steam is injected into the corresponding zone and the opening of the oxygen supply regulating damper of the zone is reduced. The exhaust signal of the maturation chamber is collected using an electronic nose module and a carbon dioxide concentration sensor. The comprehensive maturation index is calculated. When the comprehensive maturation index is not greater than the preset maturation judgment threshold and the duration is not less than the preset stable holding time, the unloading valve of the maturation chamber is opened.

8. The method according to claim 7, characterized in that, Also includes: After injecting superheated steam into the corresponding zone and reducing the opening of the oxygen supply regulating damper for that zone, the concentration signal of polycyclic aromatic hydrocarbon precursors in that zone is continuously monitored. When the concentration signal falls below the warning threshold, the superheated steam injection into the corresponding zone is shut off and the opening of the oxygen supply regulating damper for that zone is restored.

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