A gas coal seam gas downhole coal powder concentration monitoring method based on tuning fork sensing

Abstract

The application discloses a kind of gas coal seam gas downhole coal dust concentration monitoring methods based on tuning fork sensing, belong to coal dust concentration monitoring technical field, comprising: S1 deployment downhole miniaturization tuning fork concentration sensor, S2 calibration and extraction pump coal dust concentration double-state operation threshold, S3 carries out signal remote transmission and edge analysis, S4 executes intelligent judgment, S5 closed-loop automatic control and S6 system integration and full-automatic closed-loop operation.The application can also be distributed to collect and identify flowing coal dust solution and static coal dust slurry on the basis of realizing the monitoring of coal dust concentration, and real-time sensing and intelligent early warning can be realized.

Description

Technical Field

[0001] This invention relates to the field of coal powder concentration monitoring technology, and more specifically, to a method for monitoring coal powder concentration in underground gas and coalbed methane wells based on tuning fork sensors. Background Technology

[0002] Coalbed methane (CBM), as an important unconventional natural gas resource, is crucial for optimizing my country's energy structure and ensuring safe coal mine production. During CBM well drainage, the accompanying production of pulverized coal is a key issue restricting production capacity. As drainage and depressurization continue, changes in reservoir stress and fluid erosion cause coal and rock fracturing, generating a large number of micron-sized pulverized coal particles. These pulverized coal particles form a solid-liquid two-phase flow system with the drainage fluid, easily triggering a series of production problems.

[0003] Currently, the monitoring of coal powder concentration in the coalbed methane industry is based on the coal powder solution produced at the surface wellhead and obtained through testing technology. This has a certain lag, and the coal powder concentration data cannot reflect the coal powder production and aggregation degree underground in real time and cannot effectively prevent pump jamming accidents. Summary of the Invention

[0004] To address the problems existing in the prior art, the purpose of this invention is to provide a method for monitoring coal powder concentration in underground gas and coalbed methane wells based on tuning fork sensing. In addition to monitoring coal powder concentration, this invention can also collect and identify the distribution of flowing coal powder solution and static coal powder slurry, and can achieve real-time sensing and intelligent early warning.

[0005] To solve the above problems, the present invention adopts the following technical solution: A method for monitoring coal powder concentration in gas and coalbed methane wells based on tuning fork sensing includes: S1, deploying a miniaturized tuning fork concentration sensor in the well: separating the vibration component and control component of the tuning fork sensor, miniaturizing and packaging them and integrating them into the tubing short section, and then installing them; S2. Calibrate the dual-state operating threshold of pulverized coal concentration in the drainage pump: Simultaneously determine the instantaneous control threshold and the sedimentation accumulation risk threshold through field tests, and combine this dual-state threshold system with the pulverized coal carrying capacity data characterized by real-time water production to form a multi-parameter risk assessment logic. S3. Perform remote signal transmission and edge analysis: Construct a wired transmission channel through the bus, convert the tuning fork signal into a digital signal and transmit it to the ground, and analyze the data in real time to perform preliminary judgment and early warning based on the threshold calibrated by S2. S4. Execute intelligent judgment and closed-loop automatic control: The ground computer remote control system processes the received real-time coal powder concentration data, intelligently compares it with the dual-state threshold system in S2, determines the risk level, automatically generates and safely issues control commands based on the risk level, and then the ground computer remote control system continuously monitors the concentration change trend and equipment status to form a closed-loop feedback, and automatically terminates the intervention after the concentration returns to safety. S5. System Integration and Fully Automated Closed-Loop Operation: The tuning fork concentration sensor, transmission line, and ground computer remote control system are integrated and tested together for fully automated closed-loop operation.

[0006] As a preferred embodiment of the present invention, step S1 specifically includes: S101, Tuning Fork Sensor Miniaturization Customization: The vibration component and control component of the sensor are separated, re-miniaturized and packaged, and integrated into the inside of the oil pipe section; S102, Tuning fork sensor mounting structure design: Determine the sensor mounting point on the oil pipe short section of the integrated sensor; S103, Downhole Enhanced Packaging: Provides additional protection for the integrated sensor module; S104, Flow direction calibration installation: Connect the integrated and packaged tubing sub to the downhole production tubing sequence; S105. Post-installation verification and testing: Conduct full-process functional verification and joint debugging.

[0007] As a preferred embodiment of the present invention, the simulated static concentration threshold test step S2 is as follows: stop the operation of the pump, let the coal powder solution stand and the coal powder settle, then start the pump to resuspend the coal powder, and immediately measure the coal powder concentration at the bottom of the well or the pump inlet at this time. The measured concentration is the static concentration, which is the true risk level after the coal powder settles and accumulates. In step S2, the real-time flow concentration is the coal powder concentration continuously monitored by a tuning fork sensor during pump operation; the pump operating parameters are electrical parameters, mechanical vibration parameters, and hydraulic parameters; the static concentration is the concentration value measured after static disturbance; and the water production is coal powder carrying capacity data.

[0008] As a preferred embodiment of the present invention, step S3 includes: S301, Downhole Acquisition and Preprocessing: Deploy a signal conditioning and acquisition module adjacent to the downhole tuning fork sensor; S302. Construct a long-distance wired transmission channel from downhole to the surface: use cables as the physical transmission medium and reliably fix them to the downhole tubing using jumper couplings; S303, Real-time Intelligent Judgment and Control at Ground Edge: The ground industrial control computer acts as an edge computing node, running monitoring software; S304, Cloud Data Aggregation, In-depth Analysis and Optimization: While completing local real-time control, the well site monitoring software securely uploads process data to the ground computer remote control system.

[0009] As a preferred embodiment of the present invention, step S4 specifically includes: S401, Multi-source data fusion and dynamic risk assessment: The ground computer remote control system continuously receives real-time coal powder concentration data streams from downhole tuning fork sensors and performs data verification and smoothing preprocessing. S402. Generation and security triggering of hierarchical collaborative control instructions: Based on the dynamic risk assessment results determined in step S401, automatically generate hierarchical collaborative control instructions that match the results. S403. Full-parameter closed-loop monitoring and feedback during the execution process: After the collaborative control command is executed, the computer remote control system continuously monitors multiple key execution parameters in parallel to confirm that the command has been correctly implemented. S404, Adaptive Intervention Termination and System State Transition: Based on the closed-loop monitoring feedback of step S403, the ground computer remote control system determines the timing of intervention termination.

[0010] As a preferred embodiment of the present invention, step S5 specifically includes: S501. Real-time monitoring and dynamic evaluation of the effects after intervention: After automatically implementing water injection dilution and accelerated drainage intervention measures based on the judgment result of excessive coal powder concentration, the computer remote control system continuously monitors and analyzes the real-time coal powder concentration change trend transmitted back by the downhole tuning fork sensor. S502, State Transition and Full-Process Data Traceability: The ground computer remote control system presets the concentration safety recovery threshold and stabilization time conditions, and automatically generates a structured and complete event log.

[0011] As a preferred embodiment of the present invention, step S6 specifically includes: S601. Construct a modular downhole sensing and execution integrated unit and an integrated ground-to-ground connection: Integrate the tuning fork coal powder concentration sensor and cable onto the tubing short section to form a standardized downhole functional unit; S602. Deploy dual-parameter intelligent early warning software: Deploy monitoring and early warning software on the ground, complete the communication initialization with all hardware devices, and introduce real-time water production as an auxiliary parameter for judging powder carrying capacity to establish a concentration and flow rate dual-parameter early warning model. S603. Perform full-link hierarchical verification and fault safety testing: conduct testing, then conduct closed-loop simulation testing, and finally conduct safety and fault testing. S604. Start adaptive closed-loop operation and achieve full-process data traceability: Formal start-up, enter fully automatic closed-loop operation mode, the ground computer remote control system automatically records all data and generates structured operation logs.

[0012] Compared with the prior art, the advantages of this invention are: This invention achieves in-situ, real-time, and continuous measurement of pulverized coal concentration by directly deploying miniaturized and reinforced tuning fork sensors in the downhole tubing. This ensures the authenticity and timeliness of the data from the source and solves the problem of delayed surface sampling. Secondly, it proposes a dual calibration and monitoring concept for real-time flowing concentration and static concentration. By simulating the static condition of pump shutdown, the static concentration is obtained, enabling the system to not only warn of the overload risk of the current flowing fluid, but also to proactively assess the potential danger of pulverized coal sedimentation and accumulation in the wellbore. This achieves dual control over immediate and cumulative risks. By introducing water production as a key parameter for pulverized coal carrying capacity, the warning logic changes from static threshold judgment to dynamic risk assessment. The system calculates the critical value of pulverized coal that the current water production can carry in real time. Only when the measured concentration exceeds this dynamic critical value is a high-level alarm triggered. This makes the warning more scientific, greatly reduces false alarms caused by adjustments to the drainage system, and improves the accuracy and reliability of the warning. This invention achieves fully automated closed-loop control. Based on the intelligently determined risk level, the system automatically triggers a series of precise control commands, from audible and visual alarms and high-pressure water injection dilution to pump speed-up. It automatically returns to normal operation after the risk is eliminated, achieving unattended operation with a response speed in the second range. This ensures timely and consistent intervention, fundamentally solving the problems of slow manual response and non-standard operation. Secondly, the system design reflects high engineering reliability and safety. From the downhole pressure-resistant encapsulation of sensors and the redundant transmission design of armored cables, to the safety interlock checks before issuing control commands, and the fail-safe mode in case of system failure, every aspect fully considers the harsh environment and safety requirements of industrial sites. Detailed system integration and joint debugging testing procedures ensure the stability and reliability of the entire equipment upon delivery and commissioning. The system possesses powerful data value mining and continuous evolution capabilities. All operational data, including concentration curves, alarm events, control actions, and equipment status, are completely recorded and uploaded to the central platform. This not only facilitates accident tracing and production management but, more importantly, provides valuable data assets for in-depth analysis based on big data and optimization of the drainage system. Attached Figure Description

[0013] Figure 1 This is a flowchart of a method for monitoring coal powder concentration in underground gas and coalbed methane wells based on tuning fork sensing, according to the present invention. Detailed Implementation

[0014] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, 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. Example

[0015] Please see Figure 1 A method for monitoring coal powder concentration in underground gas and coalbed methane wells based on tuning fork sensing, comprising: S1, deploying a miniaturized tuning fork concentration sensor in the well; S2, Calibrate the dual-state operating threshold of pulverized coal concentration in the drainage pump; S3. Perform remote signal transmission and edge analysis; S4. Perform intelligent judgment; S5, Closed-loop automatic control; S5, system integration and fully automated closed-loop operation.

[0016] In a specific embodiment of the present invention, firstly, S1, a dedicated tuning fork concentration sensor is deployed at a key location downhole to achieve source data acquisition. Secondly, S2, through scientific experiments, quantitative judgment thresholds are established for automatic control. Then, S3, a reliable data channel and an edge-cloud collaborative analysis architecture are established to ensure real-time data upload and preliminary processing. Next, S4 and S5, based on real-time data and preset thresholds, the software automatically completes risk assessment and drives the actuator to intervene. Finally, S6, all the aforementioned hardware and software modules are integrated into an autonomously operating system, realizing a fully automated cycle of monitoring, early warning, processing, and recovery. This solution organically integrates the dispersed monitoring, transmission, analysis, and control links to form a complete solution, fundamentally changing the traditional operation mode that relies on manual labor and has delayed response. It realizes real-time perception, intelligent early warning, and automatic handling of coal dust risks in coalbed methane wells, shifting accident prevention from post-event remediation to in-event intervention and even pre-event early warning, significantly improving the automation level and safety of drainage operations, and providing a complete technical path for extending pump inspection cycles and ensuring stable gas well production.

[0017] Specifically, step S1 includes: S101. Pre-installation assessment and preparation: Assess the operating conditions of the target well section, including whether the pipe size is suitable for a 62mm diameter tubing string, whether the coal powder solution is a solid-liquid two-phase flow, and the working pressure and temperature of 10MPa. Based on the assessment results, select a tuning fork sensor, separate the vibration component and control component, and repackage and integrate them into the tubing short section. S102. Determine the installation location and method: Determine the sensor installation point on the integrated oil pipe section, and install it on the side with a downward tilt of 30 to 45 degrees. Also install a protective plate. At the same time, the space around the bottom of the tuning fork should not be less than 30 mm and the space around it should not be less than 12 mm. S103. Perform the installation operation: Connect the tubing section with the integrated tuning fork sensor into the downhole tubing sequence, and ensure that the direction of the tuning fork body of the sensor is aligned with the direction of fluid flow so that the medium can flow through the middle of the fork body, avoiding material buildup or being affected by lateral resistance. S104. Downhole packaging and protection: The tuning fork sensor is placed inside a metal outer tube. The optical fiber and the metal tube are welded together with glass solder. Then, optical high-temperature curing adhesive is filled for secondary sealing. A metal sintered filter structure is set on the packaging shell. S105. Post-installation verification and testing: Before entering the well and after installation, conduct a ground power-on test to check whether the sensor can start normally and whether the output signal is stable. At the same time, perform preliminary calibration in a simulated coal powder solution of known concentration to verify whether the inverse relationship curve between its output frequency and concentration meets expectations, and conduct joint debugging with the ground data acquisition and computer remote control system.

[0018] In specific embodiments of the present invention, the tuning fork sensor is ensured to operate stably for a long time in the harsh environment of high pressure, confined space, and solid-liquid two-phase flow in the well. Through evaluation and customized selection, the sensor performance is ensured to match the working conditions. Through scientific installation posture and spatial design, measurement accuracy is guaranteed and coal dust accumulation is prevented. Through precise convection direction installation, the medium flows through the fork body to obtain the true concentration signal. Through multiple sealing protections of metal shell, welding and potting, it resists high pressure and corrosion. Through ground joint debugging and calibration tests, the sensor performance and system compatibility are verified, realizing the in-situ installation of the sensor in the well. It can directly measure the true concentration of the well fluid, avoiding the lag and distortion of ground sampling measurement, and ensuring the long-term reliability of the sensor. Through miniaturization design, shock-resistant installation and reinforced packaging, the precision sensor can withstand the harsh environment in the well, ensuring the continuity and stability of monitoring data. This is the physical basis for realizing long-term automatic monitoring.

[0019] Specifically, step S2 includes: S201. Design field test: Determine two threshold systems for the drainage pump: one based on real-time monitored flow concentration to trigger immediate control, and the other based on simulated concentration after settling to assess the risk of sedimentation accumulation and initiate preventive maintenance. S202, Dual-state data acquisition and correlation analysis: During the experiment, real-time flow concentration, pump operating parameters, static concentration and permeate volume are recorded simultaneously, and multi-level concentration critical points are determined; S203. Establish a hazard level determination logic based on two parameters: combine the two types of thresholds obtained from the experiment with the powder carrying capacity data, input them into the computer remote control system, and form an intelligent judgment logic. S204. Threshold system configuration and closed-loop verification: The multi-level thresholds and judgment logic in step S203 are preset in the computer remote control system.

[0020] In a specific embodiment of the present invention, the threshold calibration is upgraded from a single fixed concentration value to a dynamic risk assessment system based on multiple states and parameters, resulting in more comprehensive and accurate early warnings. It can not only respond to real-time concentration exceeding the standard, but also identify the risk of sedimentation accumulation indicated by excessive static concentration. This enables multi-dimensional monitoring of pump jamming risk sources, making the judgment more intelligent. The introduction of water production as a powder-carrying capacity parameter allows the system to assess whether the current fluid can carry away the current coal powder. The early warning logic is more in line with the principles of fluid mechanics, reducing false alarms or missed alarms caused by changes in the discharge and extraction system.

[0021] Specifically, the concentration threshold test step based on simulated settling in step S201 is as follows: stop the pump operation, let the coal powder solution stand for 2 hours to allow the coal powder to settle fully, then briefly start the pump to resuspend the coal powder, and immediately measure the coal powder concentration at the bottom of the well or near the pump inlet. The measured concentration is the settling concentration, which is the true risk level after the coal powder settles and accumulates.

[0022] The real-time flow concentration is the coal powder concentration continuously monitored by a tuning fork sensor during normal pump operation. The pump operating parameters are electrical parameters, mechanical vibration parameters, and hydraulic parameters. The static concentration is the concentration value measured after static disturbance. The water production is the coal powder carrying capacity data.

[0023] The intelligent judgment logic in step S203 includes: Safe operation: When the real-time flow concentration is less than the flow warning threshold and the static concentration is less than the static risk threshold, the system is deemed safe and operates normally. Level 1 warning: When the real-time flow concentration exceeds the flow warning threshold, the system determines that immediate intervention is required and automatically executes the water injection dilution and accelerated drainage procedures; Level 2 warning: When the real-time flow concentration is not high, but the static concentration is greater than the static risk threshold, the system determines that there is a serious risk of settlement in the wellbore, issues a high-level alarm, and carries out preventive disturbance operations. Core judgment optimization: Introduce powder carrying capacity data. When the real-time flow concentration is greater than the current powder carrying capacity, the risk level will increase regardless of whether a fixed threshold has been reached.

[0024] In step S204, the system should be able to: Receives dual-channel data: simultaneously processes real-time flow concentration signals and triggered-detection static concentration signals; Implement tiered response: Based on the determined risk level, automatically trigger different levels of handling procedures such as alarms, water injection regulation, and recommended shutdown disturbances; Closed-loop verification and learning: After the system is running, it records each warning, intervention and subsequent pump status, and feeds back the optimization thresholds and logic to form a closed loop for continuous improvement.

[0025] In a specific embodiment of the present invention, the system continuously receives two signals: real-time flow concentration and periodically or triggered static concentration. The software compares the real-time data with preset flow warning thresholds and static risk thresholds, and performs multi-level judgments based on the coal powder carrying capacity calculated from the real-time water production. If safe, the system operates; if the real-time concentration exceeds the limit, it automatically injects water to accelerate the process; if the static concentration exceeds the limit, it issues a warning and suggests preventive disturbances. The system has data recording and self-learning functions, which can optimize thresholds and logic, avoiding waste of control resources and excessive intervention. Different intensity processing programs are initiated for different levels of risk, making the control actions more refined and economical, significantly improving the system's forward-looking defense capabilities. By monitoring the static concentration, an alarm can be issued in advance when a large amount of coal powder settles but has not yet affected the real-time operation of the pump, prompting preventive cleaning or adjustment of the discharge system, thereby potentially avoiding pump jamming accidents and realizing the transformation from fault repair to predictive maintenance.

[0026] Specifically, step S3 includes: S301. Downhole signal acquisition and preliminary processing; S302. Construct a long-distance wired transmission channel from the well to the surface; S303, Real-time intelligent judgment and control at the ground edge; S304, cloud-based data aggregation, in-depth analysis and optimization.

[0027] In a specific embodiment of the invention, the vibration signal of the downhole tuning fork is converted into an electrical signal, and after conditioning, analog-to-digital conversion, and encapsulation, it becomes an anti-interference digital data packet. The digital signal is reliably transmitted to the wellhead via an armored cable and RS-485 bus. The host computer on the surface edge analyzes the data in real time and immediately performs threshold-based comparisons and judgments, achieving millisecond-level local early warning and control. Simultaneously, the data is uploaded to the central platform via an encrypted network for centralized storage, historical analysis, and big data mining, ensuring the real-time performance and reliability of the control. Key risk assessments and control commands are generated at the well site edge, independent of network latency, ensuring immediate action when concentration exceeds limits. This is crucial for preventing rapidly occurring pump sticking accidents, maximizing data value. All data is aggregated in the cloud, facilitating in-depth analysis such as multi-well comparisons, trend predictions, and optimization of drainage systems, providing data support and decision-making basis for the overall production management of the block.

[0028] Specifically, the signal processing in step S301 includes: Signal conversion and conditioning: The piezoelectric element built into the tuning fork sensor converts mechanical vibration into frequency or voltage analog signals. This signal is first connected to the signal conditioning module located downhole next to the sensor, which amplifies and filters the signal. Digitalization and Packaging: The conditioned analog signal is converted into a digital signal by an analog-to-digital converter (ADC). The microcontroller is responsible for adding timestamps to the data, performing CRC checks, and packaging it into a data frame format. Step S302 specifically includes the following: Transmission medium deployment: Corrosion-resistant, shielded, dedicated armored cables are used for downhole installation, and the cables are properly secured to the tubing string using jumper couplings and other protective accessories; Communication Protocol and Networking: The RS-485 bus is used as the main communication protocol in the well. The cable adopts a 6-wire design, with two wires for sensor power supply, two wires for RS-485 digital communication, and two spare wires that are compatible with 4-20mA analog signals. Wellhead signal conversion: After the RS-485 signal reaches the wellhead, it is connected to the industrial control computer or data acquisition device on the ground through an RS-485 to Ethernet interface converter, completing the conversion from the downhole industrial bus to the interface of the ground computing equipment.

[0029] Step S303 specifically includes: Data reception and parsing: The host computer on the ground industrial control computer receives and parses the data frames from downhole in real time, extracting coal powder concentration values, time information and equipment status; Edge-side intelligent judgment and early warning: As an edge computing node, it has a built-in coal powder concentration threshold for the drainage pump calibrated from S2. It continuously compares the real-time concentration data with the threshold. Once the concentration exceeds the standard, it immediately triggers a local audible and visual alarm and executes two automatic control commands at the same time. The automatic control commands include starting the high-pressure water injection pump and accelerating the drainage speed of the drainage pump.

[0030] Step S304 specifically includes: Networked transmission: The well site industrial control computer can access the mining area network through an industrial switch, and an encrypted tunnel is established between the well site and the cloud platform using VPN virtual private network technology; Platform data integration and storage: The data access layer of the central management platform receives data from each well, performs format unification and cleaning, and then stores it in the time series database; Cloud-based in-depth analysis and optimization: Conduct historical trend retrospective analysis and multi-well comparative analysis, and use machine learning algorithms to explore the deep relationship between coal powder concentration changes and drainage system and geological conditions.

[0031] In a specific embodiment of the invention, signal processing employs a high-precision ADC and microprocessor to ensure data quality. The transmission channel uses a 6-wire armored cable, integrating power supply, digital communication, and analog backup to form a highly reliable redundant design. Edge computing is implemented by dedicated software with built-in complete control logic. Cloud analysis utilizes time-series databases and machine learning algorithms to process massive amounts of data. Through specific technology selection and design, the industrial-grade reliability and professionalism of the entire monitoring system are significantly improved. The use of RS-485 bus and armored cable ensures signal stability in complex underground electromagnetic environments and long-distance transmission. The clear division of labor between the edge and cloud not only meets the stringent requirements of real-time control but also reserves space for intelligent upgrades. Professional database and algorithm support make the system not only a monitoring tool but also a continuously evolving production analysis platform.

[0032] Specifically, step S4 includes: S401. Real-time data reception, verification and preprocessing: The ground software computer remote control system continuously receives real-time coal powder concentration data streams from the downhole tuning fork sensor and performs a series of preprocessing steps on the data before it enters the core intelligent judgment logic. S402, Threshold Comparison and Intelligent Determination of Hazard Level: The pre-processed real-time coal powder concentration value is automatically compared with the pre-calibrated and entered operating threshold of the drainage pump in S2. S403. Generation and safe issuance of automatic control commands: Based on the hazard level determined in step S402, specific control commands are automatically generated and issued to the execution device through the interface; S404, Execution Status Monitoring: The computer remote control system continuously monitors the current and outlet pressure of the water injection pump and the real-time speed and current parameters of the drainage pump to confirm that the command has been executed correctly. Step S5 specifically includes: S501, Closed-loop feedback: After the intervention measures are implemented, the system continues to monitor the trend of coal powder concentration. The concentration should show a downward trend. If the concentration does not decrease or even increases, the system will upgrade the alarm, indicating that the intervention may have failed or other faults may have occurred.

[0033] S502. Intervention Termination and System Recovery: When the real-time coal powder concentration monitoring value falls below the safety threshold and remains stable for 3 minutes, the system automatically stops the high-pressure water injection pumps sequentially or simultaneously, adjusts the speed of the drainage pumps back to the normal drainage speed, and switches the system status flag from intervention to normal monitoring. It also generates an early warning, processing, and recovery event log, recording key data such as the excess concentration, processing time, and water injection volume.

[0034] In a specific embodiment of the present invention, the system first verifies the input data, extracts effective concentration trends through verification, smoothing, and correlation of water production. Then, it compares the processed real-time data with the established multi-level threshold system to automatically determine the danger level. Based on the determination result, the system generates and safely interlocks specific water injection and drainage speed adjustment commands. After the commands are executed, the system does not stop working but continuously monitors the concentration change trend and the status of the execution equipment, forming a closed-loop feedback. If the processing is ineffective, the alarm is escalated. When the concentration returns to a safe level, the system automatically terminates the intervention and records the entire process log, completely replacing manual judgment and operation, realizing unattended automated operation, reducing labor intensity and the risk of human error, and possessing adaptive and self-diagnostic capabilities. Through closed-loop feedback, the system can evaluate its own processing effect and alarm in case of abnormalities, improving the system's intelligence level and reliability. All operations leave data traces, and the complete log provides tamper-proof data evidence for accident analysis, responsibility tracing, and process optimization.

[0035] Specifically, the data preprocessing methods in S401 include: Data validity verification: Check the integrity of data packets and the continuity of timestamps, and filter out abnormal jumps or invalid data that may be caused by transmission interference; Data smoothing: A moving average algorithm is used to smooth real-time data in the short term to identify the true concentration increase trend; Data correlation and integration: Correlation analysis between pulverized coal concentration data and real-time water production; The threshold mechanism in step S402 includes: Level 1 warning: Concentration exceeds the first critical value The system only issues an audible and visual alarm to remind human intervention; Secondary regulation: Concentration exceeds the second critical value The system determined that intervention was necessary and automatically started water injection and speed-up simultaneously. Level 3 Alert: Concentration exceeds the third critical value. While the system is processing the issue automatically, it issues the highest level alarm and performs emergency pump stoppage measures to prevent pump jamming. Judgment Logic Execution: The software's built-in control algorithm completes the above comparison and judgment in real time, and outputs a clear danger level signal and corresponding processing instruction code.

[0036] The instructions in step S403 include: Water injection command: Send a start signal to the frequency converter or start / stop controller of the high-pressure water injection pump, and set the water injection rate at low risk. High risk ; Drainage speed control command: Send commands to the motor inverter of the drainage pump via RS-485, 4-20mA or industrial Ethernet to increase the pump's operating frequency, thereby speeding up the drainage speed. The speed increase is matched with the water injection volume. Command safety interlock and issuance: Before issuing the command, the system performs a safety interlock check to confirm that the water injection pump valve is open and the drainage pump is operating normally. The command is then issued through the industrial communication module.

[0037] In a specific embodiment of the present invention, data preprocessing employs a moving average algorithm to filter out noise and identify the true trend. The early warning mechanism is explicitly set to three levels, corresponding to different response strategies, making the control more hierarchical. The control command parameters are specified to ensure the matching of intervention intensity and risk level, coordinating water injection and acceleration actions, and avoiding new production fluctuations caused by improper control. This transforms intelligent control from a conceptual logic into a parameterizable and engineerable precise operation. The quantification of thresholds and command parameters makes the system behavior predictable, adjustable, and optimizable. The hierarchical response mechanism avoids crude control and minimizes interference with normal drainage and production systems while ensuring safety, reflecting the concept of refined management and contributing to the long-term stable production of gas wells.

[0038] Specifically, step S6 includes: S601. Construct a modular downhole sensing and execution integrated unit and an integrated space-ground connection; S602, Deploy dual-parameter intelligent early warning software; S603, Perform end-to-end graded verification and fault safety testing; S604. Start adaptive closed-loop operation and realize full-process data traceability.

[0039] In a specific embodiment of the present invention, the connection between ground and air is completed through hardware integration, thresholds and logic are configured through software, and the reliability and security of the entire closed loop are verified through rigorous joint debugging tests. Finally, an intelligent monitoring and early warning processing equipment that can be started with one click and run fully automatically is delivered, ensuring the quality of the system's engineering implementation. Through standardized integration and comprehensive testing, the complexity and uncertainty of on-site installation and debugging are reduced to the greatest extent, enabling the technology to be quickly and stably replicated and promoted in different coalbed methane well sites and transformed into real productivity.

[0040] Specifically, step S601 includes: Downhole integration: The miniaturized tuning fork coal powder concentration sensor, signal transmission armored cable, water injection aluminum-plastic pipe and jumper collar protection components are integrated and installed on the tubing short section. The integrated short section can be connected to the downhole production string sequence. At the same time, all cable and pipeline connections must be strictly sealed and reinforced to withstand the downhole high pressure and corrosive environment. Ground component integration: The ground control box, high-pressure water injection pump, water injection computer remote control system, and drainage pump frequency conversion speed regulation device are integrated. The ground control box is equipped with an industrial control computer, data acquisition module and communication module, and is installed and electrically connected in the well site control room or skid-mounted platform. An industrial display screen is fixedly connected to the surface of the control box. Ground-to-ground connection: The signal cable and water injection pipeline coming up from the wellhead are reliably connected to the corresponding receiving port and water injection pump outlet on the ground through the wellhead sealing device.

[0041] Step S602 includes: Software deployment and initialization: Install the monitoring and early warning software on the ground industrial control computer. After the software starts, load the configuration file and complete the initialization and joint debugging test of the communication ports with the downhole sensors, data acquisition modules, water injection pump controllers, and drainage pump frequency converters. Key parameter preset: Input the coal powder concentration warning threshold calibrated in S2 for the drainage pump used in this well into the software system, set the control parameters according to the pump type and well condition, and introduce the coal powder carrying capacity data of water production as an auxiliary judgment basis to realize dual parameter warning of concentration and flow rate; Control logic settings: The closed-loop control logic is embedded in the software. The core logic is: real-time reception of concentration data and comparison with the preset threshold. If the concentration exceeds the limit, the water injection is started and the drainage speed is accelerated. If the concentration recovers, the water injection is stopped and the drainage speed is restored.

[0042] The test method in step S603 includes: Subsystem testing: The stability of sensor signal acquisition and transmission, the real-time performance of software data reception and display, and the accuracy and response speed of remote control of water injection pumps and drainage pumps were tested respectively. Closed-loop simulation test: By simulating a concentration signal exceeding the threshold, the test verifies whether the system can automatically and accurately trigger an early warning, start the water injection pump and accelerate drainage, and automatically stop intervention after the simulated signal returns to normal. Safety and Fault Testing: Test the system's response to communication interruptions, sensor failures, and actuator malfunctions, issue clear alarms, and enter a safe state to avoid malfunctions.

[0043] The operation method for step S604 is as follows: Routine monitoring: When the system is started, the downhole sensors begin to continuously monitor the coal powder concentration. The data is uploaded and displayed in real time, and the software continuously compares the threshold. When the concentration is below the threshold, the system is in normal monitoring mode. Early warning and automatic intervention: When the real-time concentration exceeds the preset threshold, the system will immediately trigger the closed-loop processing flow. First, it will issue an audible and visual alarm, then start the high-pressure water injection pump to inject water into the well to dilute it, and control the drainage pump to increase its speed to accelerate drainage and powder carrying. Recovery and Standby: After intervention, when the real-time concentration drops back to 80 If the safety threshold is below, the system will automatically execute a recovery command, stop the high-pressure water injection pump, and adjust the drainage pump speed back to normal, waiting for the next cycle. Data recording and traceability: Throughout the process, the system automatically records all monitoring data, alarm events, control commands and execution status, forming a complete operation log.

[0044] In specific embodiments of the present invention, the implementation of this method is highly operable, lowering the threshold for technology promotion. At the same time, it emphasizes the introduction of powder carrying capacity data and fault safety testing, further improving the advanced nature and reliability of the solution, ensuring that the system remains in a safe state even in the event of partial failure, and preventing secondary accidents.

[0045] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and its improved concept, should be covered within the scope of protection of the present invention.

Claims

1. A method for monitoring coal powder concentration in underground gas and coalbed methane wells based on tuning fork sensing, characterized in that, include: S1. Deploy a downhole miniaturized tuning fork concentration sensor: Disassemble, miniaturize, package, and integrate the vibration and control components of the tuning fork sensor into the tubing sub-section, and then install it. S2. Calibrate the dual-state operating threshold of pulverized coal concentration in the drainage pump: Simultaneously determine the instantaneous control threshold and the sedimentation accumulation risk threshold through field tests, and combine this dual-state threshold system with the pulverized coal carrying capacity data characterized by real-time water production to form a multi-parameter risk assessment logic. S3. Perform remote signal transmission and edge analysis: Construct a wired transmission channel through the bus, convert the tuning fork signal into a digital signal and transmit it to the ground, and analyze the data in real time to perform preliminary judgment and early warning based on the threshold calibrated by S2. S4. Perform intelligent judgment: The received real-time coal powder concentration data is processed by the ground computer remote control system and intelligently compared with the dual-state threshold system in S2 to determine the risk level. S5. Closed-loop automatic control: Automatically generates and safely issues control commands based on the risk level. Subsequently, the ground computer remote control system continuously monitors the concentration change trend and equipment status to form a closed-loop feedback. The intervention is automatically terminated after the concentration returns to a safe level. S6. System Integration and Fully Automated Closed-Loop Operation: The tuning fork concentration sensor, transmission line, and ground computer remote control system are integrated and tested together for fully automated closed-loop operation.

2. The method for monitoring coal powder concentration in underground gas and coalbed methane wells based on tuning fork sensing according to claim 1, characterized in that, Step S1 specifically includes: S101, Tuning Fork Sensor Miniaturization Customization: The vibration component and control component of the sensor are separated, re-miniaturized and packaged, and integrated into the inside of the oil pipe stub. S102, Tuning fork sensor mounting structure design: Determine the sensor mounting point on the oil pipe short section of the integrated sensor; S103, Downhole Enhanced Packaging: Provides additional protection for the integrated sensor module; S104, Flow direction calibration installation: Connect the integrated and packaged tubing sub to the downhole production tubing sequence; S105. Post-installation verification and testing: Conduct full-process functional verification and joint debugging.

3. The method for monitoring coal powder concentration in underground gas and coalbed methane wells based on tuning fork sensing according to claim 1, characterized in that, In step S2, a dual-state threshold system is established, which includes real-time flow concentration threshold and simulated static concentration threshold. Real-time flow concentration, pump operating parameters, static concentration and water production are collected simultaneously to determine multi-level concentration critical points. The two types of thresholds are combined with powder carrying capacity data and input into the ground computer remote control system to form intelligent judgment logic. The multi-level thresholds and judgment logic are preset in the ground computer remote control system.

4. The method for monitoring coal powder concentration in underground gas and coalbed methane wells based on tuning fork sensing according to claim 3, characterized in that, The simulated static concentration threshold test step in step S2 is as follows: stop the pump operation, let the coal powder solution stand and the coal powder settle, then start the pump to resuspend the coal powder, and immediately measure the coal powder concentration at the bottom of the well or the pump inlet. The measured concentration is the static concentration, which is the true risk level after the coal powder settles and accumulates. In step S2, the real-time flow concentration is the coal powder concentration continuously monitored by a tuning fork sensor during pump operation; the pump operating parameters are electrical parameters, mechanical vibration parameters, and hydraulic parameters; the static concentration is the concentration value measured after static disturbance; and the water production is coal powder carrying capacity data.

5. The method for monitoring coal powder concentration in underground gas and coalbed methane wells based on tuning fork sensing according to claim 1, characterized in that, Step S3 includes: S301, Downhole Acquisition and Preprocessing: Deploy a signal conditioning and acquisition module adjacent to the downhole tuning fork sensor; S302. Construct a long-distance wired transmission channel from downhole to the surface: use cables as the physical transmission medium and reliably fix them to the downhole tubing using jumper couplings; S303, Real-time Intelligent Judgment and Control at Ground Edge: The ground industrial control computer acts as an edge computing node, running monitoring software; S304, Cloud Data Aggregation, In-depth Analysis and Optimization: While completing local real-time control, the well site monitoring software securely uploads process data to the ground computer remote control system.

6. The method for monitoring coal powder concentration in underground gas and coalbed methane wells based on tuning fork sensing according to claim 1, characterized in that, Step S4 specifically includes: S401, Multi-source data fusion and dynamic risk assessment: The ground computer remote control system continuously receives real-time coal powder concentration data streams from downhole tuning fork sensors and performs data verification and smoothing preprocessing. S402. Generation and security triggering of hierarchical collaborative control instructions: Based on the dynamic risk assessment results determined in step S401, automatically generate hierarchical collaborative control instructions that match the results. S403. Full-parameter closed-loop monitoring and feedback during the execution process: After the collaborative control command is executed, the computer remote control system continuously monitors multiple key execution parameters in parallel to confirm that the command has been correctly implemented. S404, Adaptive Intervention Termination and System State Transition: Based on the closed-loop monitoring feedback of step S403, the ground computer remote control system determines the timing of intervention termination.

7. The method for monitoring coal powder concentration in underground gas and coalbed methane wells based on tuning fork sensing according to claim 1, characterized in that, Step S5 specifically includes: S501. Real-time monitoring and dynamic evaluation of the effects after intervention: After automatically implementing water injection dilution and accelerated drainage intervention measures based on the judgment result of excessive coal powder concentration, the computer remote control system continuously monitors and analyzes the real-time coal powder concentration change trend transmitted back by the downhole tuning fork sensor. S502, State Transition and Full-Process Data Traceability: The ground computer remote control system presets the concentration safety recovery threshold and stabilization time conditions, and automatically generates a structured and complete event log.

8. The method for monitoring coal powder concentration in underground gas and coalbed methane wells based on tuning fork sensing according to claim 1, characterized in that, Step S6 specifically includes: S601. Construct a modular downhole sensing and execution integrated unit and an integrated ground-to-ground connection: Integrate the tuning fork coal powder concentration sensor and cable onto the tubing short section to form a standardized downhole functional unit; S602. Deploy dual-parameter intelligent early warning software: Deploy monitoring and early warning software on the ground, complete the communication initialization with all hardware devices, and introduce real-time water production as an auxiliary parameter for judging powder carrying capacity to establish a concentration and flow rate dual-parameter early warning model. S603. Perform full-link hierarchical verification and fault safety testing: conduct testing, then conduct closed-loop simulation testing, and finally conduct safety and fault testing. S604. Start adaptive closed-loop operation and achieve full-process data traceability: Formal start-up, enter fully automatic closed-loop operation mode, the ground computer remote control system automatically records all data and generates structured operation logs.

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