Carbon dioxide gas fertilizer system based on industrial flue gas and control method thereof

Abstract

The application discloses a kind of carbon dioxide gas fertilizer systems based on industrial flue gas and control method thereof, belong to the cross field of environmental engineering and facility agriculture, the system includes industrial carbon dioxide capture and purification unit, liquefaction and centralized storage and transportation unit, centralized gas supply and vaporization pressure reduction control station, garden area level parallel pipe conveying system, greenhouse end filtration pressure stabilization and spraying unit, environmental monitoring system, internet of things transmission system, central control system and safety emergency system, through parallel pipe conveying system, the coupling of each greenhouse gas supply channel is released, and through the central control system under the constraint of centralized gas source gas supply capacity, combined with crop growth model and system response lag characteristics, the gas supply behavior of each greenhouse is cooperatively scheduled and independently controlled, the technical problems of mutual interference of multi-greenhouse gas supply and inability to independently and accurately control when sharing the same carbon dioxide gas source are solved, and the resource utilization of industrial carbon dioxide and the accurate gas fertilizer supply of large-scale agricultural park are realized.

Description

Technical Field

[0001] This invention relates to the interdisciplinary field of environmental engineering, facility agriculture engineering, automation control and artificial intelligence technology, specifically to a system for capturing, purifying, liquefying and centrally storing and transporting carbon dioxide from industrial flue gas, and supplying carbon dioxide fertilizer to multiple greenhouses through a parallel gas supply network, as well as a method for collaborative intelligent control of the system. Background Technology

[0002] Photosynthesis is the material basis for crop yield and quality. Carbon dioxide, as a key substrate for photosynthesis, directly affects the growth efficiency of greenhouse crops. In greenhouse environments, especially during the daytime when sunlight is abundant, crops rapidly consume carbon dioxide, causing its concentration to drop below 100 ppm, far below the suitable range of 800-1200 ppm for most crops' photosynthesis. This becomes the primary factor limiting high yield and quality in greenhouse agriculture.

[0003] Existing greenhouse carbon dioxide fertilization technologies mainly include combustion gasification (such as natural gas and propane combustion), chemical reaction gasification (such as the reaction of sulfuric acid and ammonium bicarbonate), bio-fermentation gasification, slow-release granules, and bottled or small storage tank gas supply. These methods generally suffer from the following problems: high gas source costs (such as bottled gas), poor stability (such as fermentation being affected by temperature), high safety risks (such as the production of harmful gases during combustion), difficulty in large-scale promotion, and failure to establish a resource-based connection with the huge social problem of industrial carbon emissions.

[0004] In terms of system architecture, existing technologies mostly adopt a decentralized deployment model of "one machine per greenhouse," with each greenhouse independently equipped with a carbon dioxide generator or control device. This results in high initial investment, numerous maintenance points, and high unit energy consumption, making it unsuitable for large agricultural parks with dozens or even hundreds of greenhouses. More importantly, when attempting to use a large centralized gas source to supply gas to multiple greenhouses, the different gas demand rhythms of crops in each greenhouse, the pressure coupling of the gas supply network, and the capacity limitations of the centralized gas source can lead to mutual interference in gas supply between greenhouses. For example, a sudden large gas consumption in one greenhouse can cause a sharp drop in gas pressure in other greenhouses, making independent and precise control impossible.

[0005] In terms of control methods, existing technologies are mostly based on simple on / off control using fixed thresholds. They fail to dynamically adjust based on crop growth stages, changes in environmental conditions, and the inherent response lag characteristics of centralized gas supply systems (including the transmission lag of gas in long-distance pipelines and the response lag of sensors). This results in low control accuracy, low carbon dioxide utilization efficiency, and even the risk of seedling damage due to excessive concentration.

[0006] Therefore, there is an urgent need for a comprehensive carbon dioxide fertilizer system and its control method that can realize the resource utilization of industrial carbon dioxide, centralized and large-scale gas supply, precise control of multiple greenhouses, and has a high level of automation and intelligence. Summary of the Invention

[0007] The present invention aims to provide a carbon dioxide fertilizer system based on industrial flue gas and its control method that overcomes the above-mentioned defects of the prior art.

[0008] The engineering problem to be solved by this invention is not simply "using industrial carbon dioxide in agriculture", but rather: in a scenario where multiple greenhouses are centrally distributed and share the same large industrial carbon dioxide gas source, how to overcome the mutual interference of gas supply between multiple greenhouses caused by the physical upper limit of gas supply capacity, pipeline pressure coupling, and system response lag, so as to achieve independent, precise, and stable gas supply control for each greenhouse.

[0009] This invention fundamentally solves the aforementioned problems by constructing an integrated system architecture and control logic of "centralized vaporization storage + parallel physical decoupling + collaborative intelligent scheduling". The choice of industrial carbon dioxide as the gas source is not only based on its advantages of large scale and low cost, but also on its characteristics of centralized storage and continuous supply, which can technically match the centralized gas supply and parallel control architecture of this invention, providing a stable gas source foundation for the independent control of multiple greenhouses.

[0010] To achieve the above objectives, the present invention provides a carbon dioxide fertilizer system based on industrial flue gas, comprising: Industrial carbon dioxide capture and purification unit: Used to separate carbon dioxide from industrial flue gas (such as cement plant and chemical plant kiln tail gas) using chemical absorption, pressure swing adsorption, or membrane separation. The gas undergoes multi-stage purification treatment including desulfurization, denitrification, and dehydration to achieve concentration and purity meeting agricultural-grade fertilizer standards (e.g., CO2 concentration ≥ 99.5%, dew point ≤ -40℃). The unit also monitors the purity, dew point, oxygen content, and SO2 levels of the carbon dioxide. x NO x The content of HF, H2S, ethylene and / or volatile organic compounds is detected, and if the test results do not meet the threshold for agricultural gas fertilizer use, the corresponding batch or gas path of carbon dioxide is prohibited from entering the carbon dioxide liquefaction and centralized storage and transportation unit.

[0011] Carbon dioxide liquefaction and centralized storage unit: used to liquefy purified carbon dioxide gas through compression and cooling, and store it in one or more large (5-50m²) units. 3 The centralized storage tank group, composed of insulated storage tanks, provides a stable gas source reserve with large-scale redundancy for the entire agricultural park.

[0012] Centralized gas supply and vaporization pressure reduction control station: includes vaporizers (such as ambient temperature or water bath type) and precision pressure regulating valve groups, used to vaporize liquid carbon dioxide and reduce high-pressure gas to a preset stable pressure suitable for pipeline transportation in the park (such as 0.6-1.0MPa).

[0013] The park-level parallel pipeline transportation system includes a primary trunk pipeline (such as a ring or branch network) and multiple parallel secondary branch pipelines. Crucially, each secondary branch pipeline is equipped with an independent, remotely controllable electrically controlled valve assembly (such as a solenoid valve or electric ball valve), and each branch originates from a different topological node of the primary trunk pipeline, thus achieving pressure decoupling and independence of each greenhouse's air supply channel in its physical structure.

[0014] Greenhouse-end filtration, pressure stabilization and spraying unit: installed at or inside each greenhouse entrance, including terminal filter, end pressure stabilizing valve (to compensate for pressure drop caused by differences in branch length), and flexible micro-orifice spraying pipeline, to release carbon dioxide into the crop canopy in a uniform, low-flow manner.

[0015] Environmental and carbon dioxide concentration monitoring system: used to collect environmental data in each greenhouse in real time. The environmental data includes at least carbon dioxide concentration, air temperature and humidity, soil temperature and humidity, photosynthetically active radiation data, ventilation status, and weather forecast data. The environmental and carbon dioxide concentration monitoring system deploys at least one monitoring node in each greenhouse. Each node integrates sensors to detect carbon dioxide concentration, air temperature and humidity, soil temperature and humidity, and photosynthetically active radiation data. The node deployment density is positively correlated with the crop planting density.

[0016] Internet of Things (IoT) data acquisition and transmission system: Through wired (such as RS-485, Ethernet) or wireless (such as LoRa, 4G / 5G, Wi-Fi) networks, the system transmits environmental data from each greenhouse, pressure data from the centralized gas supply and vaporization pressure reduction control station, pipeline flow data, and equipment status data to the central control system in real time and reliably.

[0017] Central Control System: As the decision-making core of the system, it includes an edge computing module, a data fusion module, an AI decision-making module, and an instruction execution module. The central control system is configured to: based on real-time environmental data and crop models of each greenhouse, and under the physical constraints of the overall gas supply capacity of the centralized gas supply station (such as maximum instantaneous flow rate and remaining gas volume in storage tanks), calculate the optimal gas supply control parameters (such as target concentration, valve opening duration, or PWM duty cycle) for each greenhouse at the current moment through a collaborative scheduling algorithm (such as priority-based time-division multiplexing or model predictive control), and independently drive the electrically controlled valve groups of each secondary branch pipeline.

[0018] Safety emergency and early warning system: Real-time monitoring of the pressure, concentration, and equipment status of the entire system. Once an abnormality such as overpressure in the storage tank, pipeline leakage, excessive CO2 concentration in the greenhouse, or sensor failure is detected, the system will immediately and automatically cut off the fault-related branch or the entire system, and issue audible and visual alarms and remote notifications.

[0019] In the above system structure, the centralized gas supply and vaporization pressure reduction control station, the parallel pipeline transportation system, and the central control system are highly coordinated in terms of structure, function, and control logic, forming an integrated solution of "centralized storage-parallel decoupling-coordinated control". This is the key to achieving independent and precise control of multiple greenhouses under shared gas source conditions.

[0020] The present invention also provides a control method for the above-mentioned system, comprising the following steps: Data acquisition steps: Collect data at a fixed frequency (e.g., once per minute) for each greenhouse, including at least carbon dioxide concentration, air temperature and humidity, soil temperature and humidity, photosynthetically active radiation data, ventilation status, and weather forecast data. Optional data acquisition also includes the pressure and flow rate of the centralized gas supply and vaporization pressure reduction control station.

[0021] Data transmission and preprocessing steps: The collected multi-source data is uploaded through the IoT system. The edge computing module performs local filtering, anomaly removal, and preliminary feature extraction on data with high real-time requirements.

[0022] Model Prediction and Decision-Making Steps: The AI ​​decision-making module in the central control system dynamically generates the optimal CO2 target concentration curve for each greenhouse over a future period, based on crop type (e.g., leafy vegetables, fruit vegetables), current growth stage (seedling, flowering, fruiting), and short-term weather forecasts (especially solar radiation forecasts). Then, under centralized gas source capacity constraints (e.g., avoiding excessive valve openings that could cause pipeline pressure to drop below the lower limit), fuzzy PID control or model predictive control algorithms are used to calculate the gas supply control parameters that each greenhouse needs to execute. This calculation process specifically includes compensation for system response lag: by identifying the pure lag time and inertial time between valve opening and sensor detection of concentration change, valve action is advanced or extended.

[0023] Independent execution steps: The central control system sends the calculated control parameters (such as valve ID, opening duration, and opening time) to the corresponding greenhouse's electric valve group controller via an independent network channel through the command distribution module, driving the valves to perform their actions. The actions of each valve are independent and do not interfere with each other.

[0024] Safety and Adaptive Procedures: The system monitors and executes safety logic in real time. Simultaneously, it records greenhouse concentration response data after each control action and uses machine learning algorithms to update the system's hysteresis model and crop demand model online, achieving continuous optimization of control effectiveness.

[0025] Beneficial effects Compared with the prior art, the present invention has the following beneficial effects: 1. Resource utilization and low cost: Converting industrial waste CO2 into scarce agricultural gas fertilizer reduces carbon emissions while lowering the cost of gas fertilizer by more than 70% compared to bottled gas or chemical reaction gasification.

[0026] 2. Solving the engineering challenge of independent and precise control of multiple greenhouses: By combining "parallel pipeline physical decoupling" with "cooperative scheduling algorithm considering gas source constraints," the technical bottleneck of mutual interference between gas supply from multiple greenhouses sharing a centralized gas source is fundamentally solved. Each greenhouse can independently and in real time obtain the required CO2 flow according to its own crop needs, without being affected by the gas consumption behavior of other greenhouses. This is an effect that cannot be achieved by the traditional "one greenhouse, one machine" model or simple series / parallel pipeline networks.

[0027] 3. Significant scalability and economy: Suitable for large-scale agricultural parks ranging from tens to thousands of acres. When the number of greenhouses increases, only branch lines and terminal equipment need to be added to the existing parallel pipeline network, without the need to modify the gas source and main pipeline network, resulting in low marginal costs.

[0028] 4. Precision and intelligence: By introducing AI crop models and model predictive control, the control is upgraded from "feedback based on current error" to "predictive feedforward-feedback composite control based on future demand", which significantly reduces ineffective CO2 emissions, increases the utilization rate of gas fertilizer by 20%-30%, and avoids the safety risks of exceeding concentration limits.

[0029] 5. Safety and Reliability: The system-level and branch-level dual safety mechanisms, combined with remote early warning, ensure the safe operation of large-scale industrial gas sources after they enter the agricultural environment. Attached Figure Description

[0030] Figure 1 : A schematic diagram of the overall structure of the system of the present invention.

[0031] Figure 2 Schematic diagram of industrial carbon dioxide capture and purification process.

[0032] Figure 3 Schematic diagram of a centralized liquid carbon dioxide storage and vaporization gas supply station.

[0033] Figure 4 Schematic diagram of the parallel gas supply network structure at the park level.

[0034] Figure 5 Schematic diagram of the greenhouse end filtration, pressure stabilization and spraying structure.

[0035] Figure 6Schematic diagram of the layout of environmental and carbon dioxide monitoring nodes.

[0036] Figure 7 Schematic diagram of central control system and edge computing architecture.

[0037] Figure 8 Schematic diagram of independent control logic for multiple greenhouses. Detailed Implementation

[0038] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings and specific embodiments. The described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0039] Example This example illustrates the application in a modern agricultural park of 100 mu (approximately 6.7 hectares) with 40 greenhouses: 1. System Construction This example serves a tomato and leafy vegetable rotation park covering approximately 100 acres, containing 40 standardized greenhouses. The park is adjacent to a cement plant and utilizes its flue gas emissions as a carbon source.

[0040] 1.1 Gas supply and stabilization system (see...) Figure 1 , Figure 2 , Figure 3 ) Carbon dioxide capture unit: Employs amine chemical absorption method to capture CO2 from cement plant kiln tail gas (CO2 volume concentration approximately 25%, flow rate approximately 50,000 Nm³). 3 Carbon dioxide is captured in the amine solution ( / h). The flue gas is first washed with water to cool and remove dust, and then enters the absorption tower to contact with the amine solution, where CO2 is absorbed; the rich solution enters the regeneration tower, where it is heated and desorbed to release high-concentration CO2 gas (concentration >95%).

[0041] Purification and Refinement Unit: The desorbed CO2 gas passes through the following stages in sequence: ① Alkali washing desulfurization tower (removing SO2 and H2S); ② Molecular sieve deep dehydration device (making the dew point ≤ -45℃); ③ Activated carbon deodorization tower (removing trace amounts of amine odor and VOCs). final product quality CO2 Purity ≥ 99.9%, meeting or exceeding the high-purity standard.

[0042] Centralized gas storage and supply station: A centralized gas supply station will be built on the edge of the industrial park, equipped with: Carbon dioxide compressor: pressurizes the purified low-pressure CO2 gas to 2.5 MPa.

[0043] High-pressure storage tank group: consisting of 4 30m 3It consists of parallel vertical double-walled vacuum insulated storage tanks with a design pressure of 2.8 MPa, and a total effective volume of 120 m³. 3 It can store approximately 60 tons of liquid CO2, meeting the continuous gas supply needs of the entire park for 3-5 days.

[0044] Ambient vaporizer (2 units, one in use and one on standby): Liquid CO2 enters the vaporizer and exchanges heat with the air, vaporizing into room temperature gas.

[0045] Dual-redundant pressure regulating valve group: The vaporized high-pressure gas (about 2.5MPa) is reduced in two stages, and the outlet pressure is finally stabilized at 0.8MPa ± 0.02MPa and connected to the primary trunk pipeline.

[0046] 1.2 Parallel Park Delivery System (see...) Figure 4 ) Primary main pipeline: DN100 polyethylene pipes (design pressure 1.0MPa) are used, laid underground in a "ring" shape along the main roads of the park (burial depth 1.2m). The ring structure improves the reliability of gas supply; if any part is damaged, the valves on both sides can be shut off without affecting other areas.

[0047] Secondary distribution branch: From the reserved interface on the ring main pipe, a DN75 polyethylene gas distribution manifold is led out, with each manifold branch corresponding to a greenhouse, branching out into 40 branches.

[0048] Inside the greenhouse: 40 DN75 polyethylene branch pipes are branched out, and DN20 polyethylene pipes are distributed inside the greenhouse. At the starting point of each branch (outside the greenhouse), a normally closed pulse solenoid valve (12V DC power supply, response time <1s) is installed to receive the switching command from the central control system. After each PE pipe enters the greenhouse, the nozzle position is converted to an anti-aging PU hose (for easy mobile operation) and connected to the terminal aeration equipment.

[0049] 1.3 Greenhouse Terminal and Monitoring System (see...) Figure 5 , Figure 6 ) Filtration and pressure stabilization: In each greenhouse, install the following on the DN25 polyethylene branch pipe: ① Y-type filter (100 mesh); ② Miniature pressure stabilizing valve (outlet setting 0.2MPa) to compensate for pressure fluctuations caused by differences in branch length and changes in the number of greenhouses using gas simultaneously.

[0050] Spraying unit: T-type pressure nozzles (1mm orifice diameter, 30cm orifice spacing) are used, suspended 20-50cm above the crop canopy along the tomato planting rows in a "U" shape. By adjusting the distribution and density of the T-type pressure nozzles in the greenhouse, the release pressure and flow rate are adjusted to ensure uniform carbon dioxide concentration distribution in all areas of the greenhouse.

[0051] Monitoring System: Four environmental monitoring nodes are deployed in each greenhouse (one at each of the four corners of each greenhouse). Each node integrates: ① a dual-channel NDIR CO2 sensor (range 0-5000ppm, accuracy ±30ppm); ② a digital temperature and humidity sensor (accuracy ±0.3℃, ±2%RH); ③ a silicon photovoltaic PAR sensor (range 0-2000μmol / m³). 2 / s). The data acquisition frequency is 1 minute / time.

[0052] IoT transmission: Node data is aggregated via LoRa wireless communication (470MHz band, 17dBm transmit power) to a centralized gateway deployed on the top of the gas supply station. The gateway then uploads the data to the central server via the campus LAN (fiber optic). Simultaneously, downlink control commands are transmitted in reverse through the same network to the relay modules of each solenoid valve.

[0053] 1.4 Central Management and Intelligent Decision-Making System (see...) Figure 7 ) Hardware platform: An industrial-grade server is deployed in the campus data center as the central controller (equipped with an NVIDIA Tesla T4 GPU for AI inference).

[0054] Core software and algorithms: Data fusion module: Aggregates data from various sensors every minute and calls the weather API every 3 hours to obtain hourly weather forecasts for the next 24 hours (sunlight, temperature, wind speed, and precipitation probability).

[0055] Crop Demand Model: Based on the built-in tomato (variety: Provence) growth model, the dynamic CO2 target concentration ranges for different growth stages are set as follows: seedling stage (1-20 days after transplanting) 800±100ppm, flowering and fruit setting stage (21-60 days) 1000±150ppm, and harvest stage (61-120 days) 1200±150ppm. A light compensation coefficient is also introduced: when PAR > 800μmol / m² 2 When PAR < 200 μmol / m², the target concentration is corrected upwards by 15%; 2 Stop fertilizing when the temperature reaches / s.

[0056] Collaborative decision-making algorithm: Employs a model predictive control (MPC) framework. In each control cycle (5 minutes), the algorithm executes: a. Read the current CO2 concentration, target concentration curve, current pipeline pressure (0.8MPa) of the gas supply station, and compressor / storage tank status (remaining gas volume) for each greenhouse.

[0057] b. Establish the prediction model: C_i(t+1) = a_i * C_i(t) + b_i * u_i(t-τ_i) + d_i * E_i(t), where u is the valve opening time, τ is the system lag time (obtained through online identification), and E is the external disturbance (lighting, ventilation).

[0058] c. Under the constraint of total instantaneous gas supply flow rate ∑(F_i * u_i) ≤ Q_max, find the valve control sequence that minimizes the sum of squared future concentration tracking errors for each greenhouse. A quadratic programming algorithm is used, with a computation period of <1 second.

[0059] Command execution: Generate the on / off sequence of the solenoid valve for each greenhouse for the next 5 minutes (e.g., "Valve #15: Open for 60 seconds, Close for 240 seconds, cycle"), and send it to the distributed I / O module via the Modbus-TCP protocol. The latter drives the relay to control the solenoid valve.

[0060] Manual intervention interface: Provides web and WeChat mini-program interfaces. Administrators can view real-time data and historical curves of each greenhouse at any time, and set manual commands such as "force shutdown", "quantitative gas supply (e.g., on for 5 minutes)" and "temporarily modify target concentration". Manual commands have higher priority than AI decisions.

[0061] 2. System workflow (see...) Figure 8 ) Take a typical sunny morning in spring as an example: 06:00: The central server starts up and retrieves the weather forecast: Sunny today, strong sunlight in the morning, cloudy in the afternoon, high of 28℃. The system loads information on all greenhouse crops (most tomatoes are in the flowering and fruit-setting stage, and 5 leafy vegetable greenhouses are in the harvesting stage).

[0062] 08:30: With increased light intensity, the PAR sensor readings in each greenhouse rose to 300-500 μmol / m³. 2 / s. The central control system initiates fertilization preparation. For tomato greenhouses during the flowering and fruit-setting period, the dynamic target concentration is set at 1000 ppm; for leafy vegetable greenhouses during the harvest period, it is set at 800 ppm.

[0063] 09:00: The CO2 concentration in greenhouse No. 1 (tomato greenhouse) dropped to 380 ppm (below the target lower limit of 850 ppm). After calculation, the MPC controller generated the instruction: "Open the solenoid valve of greenhouse No. 1 for 90 seconds." The valve opened, and CO2 gas began to be released through the branch pipe and the microporous pipe inside the greenhouse. At the same time, the system anticipated that the concentration in greenhouse No. 15 would also fall below the threshold in 5 minutes, but to avoid exceeding the total instantaneous flow limit, valve No. 15 was opened immediately after valve No. 1 was closed.

[0064] 09:05: The sensor in greenhouse No. 1 detected a CO2 concentration of 1050 ppm. The system confirmed that the rate of increase was in line with the prediction and there were no abnormalities. Greenhouse No. 15 started supplying gas for 70 seconds.

[0065] 09:10-11:30: The system continuously performs dynamic scheduling. During this period, due to fluctuations in sunlight, the target concentration in some greenhouses was adjusted up and down; the instantaneous flow rate of the gas supply station was always constrained by the MPC controller to the maximum safe value (approximately 1000 Nm³). 3 Within / h). A Gantt chart effect of multiple greenhouse "pulse-like" overlapping gas supplies appeared (see...). Figure 8 Each greenhouse receives an average of 5-8 minutes of cumulative gas supply per hour, with the concentration remaining stable in the range of 900-1100 ppm.

[0066] 11:40: The clouds predicted in the weather forecast arrived, and the PAR sensor readings in all greenhouses plummeted to 150 μmol / m³. 2 Below / s. The target concentration for all greenhouses was dynamically reduced to 500ppm (to maintain the baseline concentration), and gas supply to most was stopped. The system entered "energy-saving standby" mode.

[0067] Throughout the day, the system executed approximately 12,000 valve actions, with a total gas supply of approximately 8,000 Nm³. 3 The root mean square error (RMSE) of CO2 concentration control in each greenhouse was below 80 ppm, with no alarms triggered for exceeding limits. Compared to the traditional fixed threshold control method, this resulted in approximately 25% savings in CO2 gas.

[0068] 3. Safety and Emergency Examples One day, in greenhouse No. 17, the CO2 concentration could not accumulate effectively because the ventilation vent was not closed. However, the system monitoring showed that after 180 seconds of continuous gas supply, the concentration rise rate in greenhouse No. 17 was only 10% of the normal value. The AI ​​model determined that this was due to "sensor malfunction or greenhouse leakage".

[0069] Emergency Response: The system immediately and automatically executes the following: ① Close the solenoid valve of greenhouse No. 17 to stop the gas supply; ② Lock the gas supply permission for this greenhouse to prevent accidental opening; ③ Highlight greenhouse No. 17 on the central control room screen and pop up an alarm window; ④ Send an alarm message to the park administrator via WeChat: "[High Risk Alarm] Greenhouse No. 17 CO2 response is abnormal, suspected leak, gas supply has been automatically cut off, please check and repair immediately."

[0070] After receiving the notification, the administrator checked and found that a malfunction in the ventilation actuator was causing the vent to remain open. After repair, clicking "Clear Alarm / Reset" on the mobile app unlocked the system and restored normal air supply.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A carbon dioxide fertilizer system based on industrial flue gas, characterized in that, include: Industrial carbon dioxide capture and purification units are used to separate and purify carbon dioxide from industrial flue gas, and to control the purity, dew point, oxygen content, and SO2 levels of the carbon dioxide. x NO x The content of HF, H2S, ethylene and / or volatile organic compounds was detected; A carbon dioxide liquefaction and centralized storage and transportation unit is used to liquefy and store purified carbon dioxide. Centralized gas supply and vaporization pressure reduction control station is used to vaporize liquid carbon dioxide and reduce the pressure to the gas supply pressure; The park-level parallel pipeline transportation system includes a primary main pipeline and multiple parallel secondary branch pipelines. Each secondary branch pipeline is equipped with an independent electrically controlled valve group for connecting to each greenhouse. The greenhouse-end filtration, pressure stabilization and spraying unit is installed inside each greenhouse and connected to the corresponding secondary branch pipeline; An environmental and carbon dioxide concentration monitoring system is used to collect environmental data in each greenhouse in real time. The environmental data includes at least carbon dioxide concentration, air temperature and humidity, soil temperature and humidity, photosynthetically active radiation data, ventilation status, and weather forecast data. The Internet of Things (IoT) data acquisition and transmission system is used to transmit the environmental data, pressure data from the centralized gas supply and vaporization pressure reduction control station, pipeline flow data, and equipment status data to the central control system. as well as The central control system is connected to the electrically controlled valve group and the Internet of Things data acquisition and transmission system respectively. The central control system is configured to: based on the environmental data in each greenhouse, under the constraint of the gas supply capacity of the centralized gas supply and vaporization pressure reduction control station, collaboratively calculate the gas supply control parameters corresponding to each greenhouse, and independently control the electrically controlled valve group on each secondary branch pipeline based on the gas supply control parameters, so as to achieve independent and precise gas supply control of multiple greenhouses sharing the same carbon dioxide gas source without interference. and / or The environmental and carbon dioxide concentration monitoring system deploys at least one monitoring node in each greenhouse. Each node integrates sensors to detect carbon dioxide concentration, air temperature and humidity, soil temperature and humidity, and photosynthetically active radiation data. The node deployment density is positively correlated with the crop planting density.

2. The carbon dioxide fertilizer system based on industrial flue gas according to claim 1, characterized in that, The centralized gas supply and vaporization pressure reduction control station includes: At least 5-50m 3 Liquid carbon dioxide storage tanks are used to provide centralized gas source reserves; Ambient or water bath vaporizers are used to convert liquid carbon dioxide into gas; and A multi-stage redundant pressure regulating valve assembly is used to stabilize the pressure of vaporized carbon dioxide gas within a preset delivery pressure range.

3. The carbon dioxide fertilizer system based on industrial flue gas according to claim 1, characterized in that, The primary trunk pipeline of the park-level parallel pipeline transportation system is laid underground in a ring or branch network topology. Each secondary branch pipeline is led out from a different node on the primary trunk pipeline, and the secondary branch pipelines are physically independent of each other to structurally decouple the gas supply between the greenhouses.

4. The carbon dioxide fertilizer system based on industrial flue gas according to claim 1, characterized in that, The central control system includes: The data fusion module is used to perform spatiotemporal alignment and fusion of collected environmental data and weather forecast data; Edge computing modules, deployed on gateways or controllers near the greenhouse, are used for local preprocessing and rapid response to control commands with high real-time requirements; The AI ​​decision-making module incorporates decision-making algorithms based on crop growth models, environmental demand models, and historical data to dynamically calculate the target carbon dioxide concentration and gas supply pulse duration for each greenhouse at different times; and The instruction issuance and execution module is used to send the calculated gas supply control parameters to the corresponding electronically controlled valve group via wired or wireless network.

5. The carbon dioxide fertilizer system based on industrial flue gas according to claim 1, characterized in that, The greenhouse-end filtration, pressure stabilization, and spraying unit includes: Terminal filters are used to remove impurities from pipelines; End-of-line pressure regulating valves are used to compensate for pressure fluctuations caused by differences in branch lengths and variations in the number of valves opened simultaneously; and Flexible micro-orifice spray pipes are evenly arranged above the crop canopy or between rows in the greenhouse to release carbon dioxide in a low-flow, large-area manner.

6. The carbon dioxide fertilizer system based on industrial flue gas according to claim 1, characterized in that, It also includes a safety emergency and early warning system, which is independent of or integrated into the central control system and is configured as follows: Real-time monitoring of the pressure and level of the liquid carbon dioxide storage tank, as well as the pressure of the primary main pipeline and secondary branch pipeline; When the carbon dioxide concentration in any greenhouse exceeds the preset safety limit or a sensor malfunctions, the system automatically locks and closes the electrically controlled valve group on the corresponding secondary branch pipeline of that greenhouse, and sends an alarm message containing the location and type of the fault to the administrator.

7. A campus-level parallel gas supply network structure for the system according to any one of claims 1 to 6, characterized in that, include: A primary trunk pipeline, the inlet end of which is connected to the output end of the centralized gas supply and vaporization pressure reduction control station; One or more gas distribution manifolds are connected to the primary trunk pipeline; as well as Multiple secondary branch pipelines, one end of each secondary branch pipeline is connected to the gas distribution manifold via an independent electrically controlled valve group, and the other end is connected to a corresponding greenhouse; The secondary branch pipelines are arranged in parallel in space, and their length and diameter are determined independently according to the gas supply distance and design flow rate of the corresponding greenhouse.

8. A centralized gas supply coordinated scheduling method for the system according to any one of claims 1 to 6, characterized in that, When calculating the gas supply control parameters for each greenhouse, the central control system performs the following steps: Obtain the maximum instantaneous gas supply capacity and remaining gas supply capacity of the centralized gas supply and vaporization pressure reduction control station; Service requests from multiple greenhouses are sorted according to their current priority or urgency. as well as Under the constraints of the maximum instantaneous gas supply capacity and the remaining gas supply capacity, time-division multiplexing or flow distribution algorithms are used to generate timing control commands for each electrically controlled valve group, so as to avoid a sudden drop in system pressure caused by multiple electrically controlled valve groups opening at high flow rates at the same time.

9. A control method for a carbon dioxide fertilizer system based on industrial flue gas, characterized in that, The system applied to any one of claims 1 to 6 comprises the following steps: Data acquisition steps: The environmental and carbon dioxide concentration monitoring system is used to collect environmental data in each greenhouse in real time. The environmental data includes at least carbon dioxide concentration, air temperature and humidity, soil temperature and humidity, photosynthetically active radiation data, ventilation status, and weather forecast data. Data transmission steps: The collected environmental data is uploaded to the central control system through the IoT data acquisition and transmission system; Model prediction steps: The central control system dynamically predicts and sets the optimal carbon dioxide target concentration curve for each greenhouse based on the crop type, growth stage, and weather forecast data for a preset future time period. Collaborative decision-making steps: Under the constraint of the gas supply capacity of the centralized gas supply and vaporization pressure reduction control station, the central control system, based on the optimal carbon dioxide target concentration curve and real-time environmental data, uses a fuzzy PID control algorithm or a model predictive control algorithm to calculate the gas supply control parameters required for each greenhouse to bridge the difference between the current concentration and the target concentration. The calculation process includes compensating for the lag time of pipeline transmission and sensor response; and Independent execution steps: The central control system independently controls the opening and closing time of the electrically controlled valve groups on the secondary branch pipelines connected to each greenhouse according to the calculated gas supply control parameters, thereby realizing independent and precise gas supply to multiple greenhouses sharing the same carbon dioxide gas source without interference.

10. The control method according to claim 9, characterized in that, In the collaborative decision-making step, the gas supply control parameters include at least: the opening time, opening duration and / or pulse width modulation duty cycle of each electronically controlled valve group; and / or The independent execution steps adopt an event-driven control mode: when the central control system detects that the real-time carbon dioxide concentration of any greenhouse is lower than its dynamic target concentration lower limit, it immediately generates an opening command; when it detects that the concentration is higher than the dynamic target concentration upper limit, it immediately generates a closing command. and / or The central control system records the action history of each electronically controlled valve group and the response curve of environmental changes in each greenhouse. It uses machine learning algorithms to automatically update the crop demand model and the system hysteresis compensation model to achieve online optimization of control parameters. and / or It also includes a manual intervention step: providing a visual human-computer interaction interface to receive manual control modes, forced gas supply commands, or target concentration correction values ​​for specific greenhouses set by the administrator, and the priority of the manual intervention step is higher than that of the collaborative decision-making step.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements all or part of the steps of the method of claim 9.

Images