Method for transforming coal mine gas extraction pipe network system

Abstract

The invention relates to the technical field of coal mine gas extraction, and provides a coal mine gas extraction pipe network system transformation method which comprises the following steps: closing a main control valve of a main extraction pipeline and a branch control valve of an extraction branch to be transformed; a temporary extraction branch is connected between the branch control valve and the main extraction pipeline, a temporary extraction channel connected with the original extraction branch in parallel is formed, and the main control valve and a temporary control valve on the temporary extraction branch are opened; in the state that the temporary extraction branch maintains extraction, the original extraction branch is transformed and constructed; after the original extraction branch is transformed, the branch control valve is opened, the temporary control valve is closed, the temporary extraction branch is dismantled, and gas extraction is switched to the transformed extraction branch. On the premise that the whole extraction system keeps normal operation, transformation operation of a pipeline system can be completed, gas accumulation is effectively prevented by establishing a temporary independent gas extraction branch in the transformation process, the transformation process is safe and efficient, and the labor intensity of operators is greatly reduced.

Description

Technical Field

[0001] This application relates to the field of coal mine gas extraction technology, and more specifically, to a method for modifying a coal mine gas extraction pipeline system. Background Technology

[0002] In coal mine gas control, establishing a complete surface or underground gas extraction system and ensuring its safe and efficient operation are key measures to address coal and gas outbursts and high-gas mine disasters. However, in actual operation, the pipeline network, pumping station equipment, and related safety facilities of the extraction system inevitably malfunction and require maintenance, or the original pipeline network needs to be modified due to system optimization or other reasons.

[0003] Currently, when carrying out such maintenance and modification work, the extraction system is usually shut down completely or partially to ensure operational safety. This approach has the following prominent problems: Impact on extraction continuity: During maintenance or renovation, extraction operations need to be interrupted, which will directly affect the normal extraction effect of the local area or even the entire system and reduce the efficiency of gas control.

[0004] High safety risks: If safety technical measures are not well formulated or properly implemented during shutdown maintenance or renovation, gas disasters are very likely to occur, which may cause significant economic losses and reputational damage to coal mining enterprises.

[0005] Therefore, how to safely and efficiently complete the maintenance and renovation of the gas extraction system under the condition of continuous or minimal gas extraction is a problem that urgently needs to be solved in current technical practice. Summary of the Invention

[0006] To address at least one of the aforementioned technical problems, this application proposes a method for modifying a coal mine gas extraction pipeline system.

[0007] In view of this, this application proposes a method for upgrading a coal mine gas drainage pipeline system. The coal mine gas drainage pipeline system includes a main drainage pipeline and multiple drainage branches. The method is used to upgrade and renovate a target drainage branch while maintaining continuous gas drainage. The method includes the following steps: closing the main control valve of the main drainage pipeline and the branch control valve of the drainage branch to be upgraded; connecting a temporary drainage branch between the branch control valve and the main drainage pipeline to form a temporary drainage channel in parallel with the original drainage branch, and opening the main control valve and the temporary control valve on the temporary drainage branch; carrying out the upgrade construction of the original drainage branch while the temporary drainage branch maintains drainage; after the upgrade of the original drainage branch is completed, opening the branch control valve, closing the temporary control valve, and dismantling the temporary drainage branch, switching the gas drainage to the upgraded drainage branch.

[0008] In some feasible methods, a connection structure for connecting temporary extraction branches is pre-installed on the main extraction pipeline. The connection structure is a prefabricated bypass assembly with multiple branch interfaces integrated on the pipe wall of the bypass assembly, and each branch interface is equipped with an independent valve.

[0009] In some feasible ways, connecting a temporary extraction branch includes using a transparent PVC wire hose to connect the branch control valve to a selected branch interface.

[0010] In some feasible methods, the original extraction branch is modified, including: connecting a monitoring process pipe section with multiple sensor interfaces to the original extraction branch; installing sensors on the sensor interfaces and connecting the sensor data to a remote monitoring system; wherein the sensors include at least one of a carbon monoxide sensor, a laser methane sensor, and an ultrasonic gas flow sensor.

[0011] In some feasible methods, the process of connecting the temporary extraction branch also includes: installing an adjustment module on the temporary extraction branch, the adjustment module including an adjustment valve and a flow meter; and adjusting the opening of the adjustment valve to match the gas flow rate through the temporary extraction branch with the target extraction flow rate.

[0012] In some feasible methods, after opening the main control valve and the temporary control valve, and before the temporary extraction branch is officially put into extraction, there are also commissioning preparation and verification steps: injecting inert gas or compressed air into the temporary extraction branch for gas replacement, and monitoring with a gas concentration sensor to confirm that the gas concentration in the pipe is lower than the safety threshold; opening the temporary control valve, monitoring the flow rate with a flow meter installed on the temporary extraction branch, and adjusting the regulating valve on the temporary extraction branch to control the flow rate within the target extraction flow rate range.

[0013] In some feasible ways, the commissioning preparation and verification steps also include: monitoring and adjusting the inlet pressure of the temporary extraction branch so that the difference between the inlet pressure of the temporary extraction branch and the inlet pressure of the original extraction branch in the closed state is less than a set value.

[0014] In some feasible methods, before connecting the temporary extraction branch, the method further includes: setting up a local ventilation device and an emergency extraction pump near the borehole to be modified; the inlet of the emergency extraction pump is connected in parallel with the temporary extraction branch through a three-way valve; when the gas concentration at the borehole exceeds a first set threshold, the local ventilation device is automatically activated; when the gas concentration exceeds a higher second set threshold, the three-way valve is automatically switched and the emergency extraction pump is activated to introduce the gas into the emergency discharge pipeline.

[0015] In some feasible methods, before connecting the temporary extraction branches, the method further includes: preparing a corresponding number of temporary extraction branches, monitoring process pipe sections, and transition pipe fittings for parallel connection between the temporary extraction branches and the main extraction pipeline, based on the number of boreholes in the drilling site to be modified; wherein, the transition pipe fittings include butterfly valves, transparent PVC steel wire hoses, first short section pipes and second short section pipes, the first short section pipes are provided with multiple branch interfaces matching the number of boreholes, and each branch interface is correspondingly equipped with a ball valve.

[0016] In some feasible methods, the main extraction pipeline and multiple extraction branches are connected by a gas collection box, which is connected to the multiple extraction branches via a manifold. The method also includes: after closing the main control valve of the main extraction pipeline and the branch control valve of the extraction branch to be modified, installing a first short section pipeline and a butterfly valve at the interface between the gas collection box and the manifold, and ensuring that the butterfly valve is in the closed state; cutting off the manifold on the side of the butterfly valve near the manifold; and after the original extraction branch is modified, connecting the cut-off manifold via a second short section pipeline.

[0017] Compared with related technologies, this application has the following technical advantages: This application proposes a method for modifying a coal mine gas drainage pipeline system, aiming to solve the technical challenges of pipeline modification in existing coal mine gas drainage systems. This process has the following characteristics: 1. Achieve uninterrupted pumping modification: The pipeline system can be modified while the entire pumping system is in normal operation, including adding or removing pipelines and related accessories, without affecting the normal negative pressure pumping at the drilling site.

[0018] II. Ensuring operational safety: During the renovation process, temporary independent gas extraction branches are established to effectively prevent gas accumulation, ensure that the gas concentration always meets national safety regulations, and eliminate illegal and over-limit operations.

[0019] III. Improved Operational Efficiency: The modification process is safe and efficient, significantly reducing the labor intensity of operators. Only two people are needed per shift to complete the pipeline replacement task, eliminating the need for frequent valve opening and closing and simplifying the operation process.

[0020] Additional aspects and advantages of this application will become apparent in the following description or may be learned by practice of this application. Attached Figure Description

[0021] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 A flowchart illustrating a method for modifying a coal mine gas drainage pipeline system according to one embodiment of this application is shown. Figure 2This paper shows a schematic diagram of a coal mine gas drainage pipeline system before modification in one embodiment of this application; Figure 3 It shows Figure 2 Enlarged view of part E in the embodiment; Figure 4 This paper shows a schematic diagram of a coal mine gas drainage pipeline network system after adding a temporary drainage branch in one embodiment of this application; Figure 5 It shows Figure 4 Enlarged view of part F in the embodiment.

[0022] in, Figures 2 to 5 The correspondence between the reference numerals and component names in the attached drawings is as follows: 110 First seamless steel pipe, 120 First ball valve, 130 Gate valve, 140 Flange, 150 Second ball valve, 152 Third ball valve, 160 Black PVC steel wire hose, 170 Second seamless steel pipe, 172 First pipe section, 174 Second pipe section, 180 Transparent PVC steel wire hose, 190 First butterfly valve, 192 Second butterfly valve, 200 First short section pipe, 210 Second short section pipe, 220 Observation pipe, 230 Gas collection box. Detailed Implementation

[0023] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0024] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0025] The following reference Figures 1 to 5 This application describes a method for modifying a coal mine gas extraction pipeline system according to some embodiments.

[0026] like Figure 1 As shown, this application proposes a method for upgrading a coal mine gas drainage pipeline system. The coal mine gas drainage pipeline system includes a main drainage pipeline and multiple drainage branches. The method is used to upgrade and renovate the target drainage branches while maintaining continuous gas drainage, and includes the following steps: S202: Close the main control valve of the main extraction pipeline and the branch control valve of the extraction branch to be modified; S204: Connect a temporary extraction branch between the branch control valve and the main extraction pipeline to form a temporary extraction channel in parallel with the original extraction branch, and open the main control valve and the temporary control valve on the temporary extraction branch. S206: While maintaining extraction in the temporary extraction branch, the original extraction branch shall be modified and constructed. S208: After the original extraction branch is modified, open the branch control valve, close the temporary control valve and dismantle the temporary extraction branch, and switch the gas extraction to the modified extraction branch.

[0027] The coal mine gas drainage pipeline system modification method provided in this application achieves the upgrading and modification of the target branch without interrupting drainage or production by connecting a temporary drainage branch in parallel with the original drainage branch. The method involves closing the relevant valves, connecting the temporary drainage branch between the branch control valve and the main drainage pipeline to form a parallel temporary drainage channel; then opening the temporary channel to maintain drainage while construction is carried out on the original branch; after the modification is completed, switching back to the modified branch and dismantling the temporary pipeline.

[0028] This modification method maintains continuous gas extraction by setting up temporary extraction channels. Traditional modification methods often require a complete or large-scale shutdown of extraction, which can easily lead to gas accumulation underground and cause safety accidents. This method effectively overcomes the safety risks caused by stopping extraction, ensures coal mine production safety, and maintains underground gas concentration within a safe range.

[0029] Traditional gas extraction retrofits often involve large-scale shutdowns, severely impacting production schedules. This method, however, only requires localized operations, significantly shortening the construction period and reducing economic losses caused by downtime. Furthermore, temporary pipelines can be reused, further reducing retrofit costs. Moreover, the elimination of the need to wait for a complete shutdown before retrofitting reduces the time spent on stopping and restarting the extraction system, facilitating the rapid restoration of normal operation of extraction branches and increasing gas extraction volume.

[0030] By adopting a start-then-stop switching process, the original branch is constructed after the temporary branch is put into use, which avoids sudden changes in system pressure and airflow impact, ensures the stable operation of the pipeline network, and improves the reliability of the system after the renovation.

[0031] The coal mine gas drainage pipeline system modification method provided in this application has clear operation steps and is easy to implement. The entire modification process is carried out by controlling the opening and closing of the main control valve, branch control valve and temporary control valve, as well as the connection and dismantling of temporary drainage branches. The technical requirements for on-site operators are relatively low, which reduces the difficulty and cost of modification.

[0032] In some embodiments provided in this application, a connection structure for connecting temporary extraction branches is pre-installed on the main extraction pipeline. The connection structure is a prefabricated bypass assembly. Multiple branch interfaces are integrated on the pipe wall of the bypass assembly, and each branch interface is equipped with an independent valve.

[0033] In this embodiment, the bypass component integrates multiple branch interfaces with independent valves. When the target extraction branch needs to be modified, the temporary extraction branch can be quickly and accurately connected to the appropriate branch interface without the need for on-site temporary processing of connection parts. This shortens the preparation time before the modification, enables the modification work to be carried out quickly, and effectively compresses the overall modification period.

[0034] Independent valves allow each branch interface to be controlled independently. During the renovation process, specific interfaces can be flexibly opened or closed according to actual needs, and the gas extraction path can be precisely controlled. This ensures the stable operation of temporary extraction branches and facilitates the renovation of the original extraction branches, reducing the difficulty of operation.

[0035] The prefabricated bypass components are of reliable quality and are tightly connected to the main extraction pipeline, reducing problems such as poor sealing that may occur due to temporary on-site connections. This ensures the stable operation of the gas extraction system during the renovation period, maintains safe underground gas concentrations, and provides strong support for safe coal mine production.

[0036] In some embodiments provided in this application, connecting a temporary extraction branch includes: using a transparent PVC wire hose to connect the branch control valve to a selected branch interface.

[0037] In this embodiment, the transparent tube allows operators to directly observe the gas flow and condensate accumulation inside the tube, enabling visual monitoring of the extraction process. This facilitates timely judgment of whether the pipeline is unobstructed and whether the extraction is normal, thus improving operational safety and controllability.

[0038] This hose combines flexibility and strength. Its flexibility allows for flexible and convenient installation, adapting to limited working space and complex routes downhole, significantly reducing connection difficulty; the embedded steel wire structure ensures the pipeline's resistance to collapse under negative pressure extraction conditions, ensuring the reliable operation of temporary channels.

[0039] In addition, PVC materials are relatively inexpensive, and the hoses can be disassembled and reused, further reducing the cost of modification.

[0040] In some embodiments provided in this application, the modification of the original extraction branch includes: connecting a monitoring process pipe section with multiple sensor interfaces to the original extraction branch; installing sensors on the sensor interfaces and connecting the sensor data to a remote monitoring system; wherein the sensors include at least one of a carbon monoxide sensor, a laser methane sensor, and an ultrasonic gas flow sensor.

[0041] In this embodiment, a monitoring process pipe section equipped with multiple sensor interfaces is connected and fitted with carbon monoxide sensors, laser methane sensors, etc., enabling comprehensive real-time monitoring of the gas extraction environment. The carbon monoxide sensor can promptly detect harmful gases produced by spontaneous combustion of coal, while the laser methane sensor can accurately detect methane concentration. If the concentration exceeds the standard, an alarm can be issued quickly, effectively preventing major safety accidents such as gas explosions and providing a solid guarantee for the safety of underground workers.

[0042] Ultrasonic gas flow sensors can accurately measure gas flow. After the data is connected to a remote monitoring system, the gas extraction volume of each extraction branch can be monitored in real time. By analyzing this data, branches with low extraction efficiency can be identified in a timely manner, allowing for targeted adjustments to extraction parameters or maintenance, thereby improving overall gas extraction efficiency and increasing gas resource recovery.

[0043] The application of the remote monitoring system enables centralized management and remote viewing of data. Managers can keep track of the operation status of the extraction branch at any time without having to be on-site, making it easier to make timely decisions.

[0044] In some embodiments provided in this application, the method further includes: installing an adjustment module on the temporary extraction branch, the adjustment module including an adjustment valve and a flow meter; and adjusting the opening of the adjustment valve to match the gas flow rate through the temporary extraction branch with the target extraction flow rate.

[0045] In this embodiment, a regulating module including a regulating valve and a flow meter is installed on the temporary extraction branch, enabling precise adjustment of the gas flow rate. The flow meter monitors the gas flow rate through the temporary extraction branch in real time, and then the opening of the regulating valve is precisely adjusted according to the target extraction flow rate, ensuring that the actual flow rate matches the target value. This ensures that the gas extraction volume remains stable within a reasonable range, avoiding the impact of excessive or insufficient flow on the extraction effect and guaranteeing the stable operation of the gas extraction system.

[0046] Precise flow control helps maintain a balance in underground gas concentration. A stable extraction flow rate can effectively prevent gas accumulation, reduce the risk of safety accidents such as gas explosions, and create a safe working environment for underground workers.

[0047] Furthermore, this solution enhances the flexibility and adaptability of the retrofit process. Faced with varying extraction needs and operating conditions, the flow rate of temporary extraction branches can be quickly adjusted without requiring large-scale adjustments to the overall extraction system, reducing retrofit time and costs, and improving the efficiency and feasibility of retrofitting coal mine gas extraction pipeline networks.

[0048] In some embodiments provided in this application, after the main control valve and the temporary control valve are opened, and before the temporary extraction branch is officially put into extraction, the following preparation and verification steps are also included: injecting inert gas or compressed air into the temporary extraction branch for gas replacement, and monitoring with a gas concentration sensor to confirm that the gas concentration in the pipe is lower than the safety threshold; opening the temporary control valve, monitoring the flow rate with a flow meter installed on the temporary extraction branch, and adjusting the regulating valve on the temporary extraction branch to control the flow rate within the target extraction flow rate range.

[0049] In this embodiment, injecting inert gas or compressed air into the temporary extraction branch for gas replacement effectively removes residual gas from the pipe. Precise monitoring using a gas concentration sensor confirms that the gas concentration inside the pipe is below the safe threshold, reducing the risk of explosions caused by gas mixing with air and reaching explosive limits. This creates a safe environment for subsequent extraction operations and effectively protects the lives of personnel working underground.

[0050] After the temporary control valve is opened, the flow rate is monitored in real time using a flow meter installed on the temporary extraction branch, allowing operators to intuitively grasp the actual situation of gas extraction. By adjusting the regulating valve on the temporary extraction branch, the flow rate is precisely controlled within the target extraction flow rate range, ensuring the stability and accuracy of gas extraction. This enables the extraction system to operate efficiently according to predetermined parameters, improving the recovery and utilization rate of gas resources.

[0051] These preparatory and verification steps, as crucial components of the modification process, provide reliable verification methods for the formal commissioning of temporary gas drainage branches. Early identification and resolution of potential problems ensure the smooth progress of the entire modification process and improve the quality and reliability of the coal mine gas drainage pipeline system modification.

[0052] In some embodiments provided in this application, the commissioning preparation and verification steps further include: monitoring and adjusting the inlet pressure of the temporary extraction branch so that the difference between the inlet pressure of the temporary extraction branch and the inlet pressure of the original extraction branch in the closed state is less than a set value.

[0053] In this embodiment, ensuring that the pressure difference between the inlet pressure of the temporary extraction branch and the inlet pressure of the original extraction branch in the closed state is less than a set value effectively avoids the impact on the pipeline system caused by excessive pressure differences. A smooth pressure transition prevents vibration and leakage problems in the pipeline network due to sudden pressure changes, ensuring the stable operation of the entire gas extraction pipeline network system during the renovation process, reducing the risk of equipment damage, and extending the service life of the pipeline network.

[0054] Proper pressure matching helps maintain the continuity and uniformity of gas drainage. Keeping the pressure difference within a small range ensures that temporary drainage branches and original drainage branches coordinate with each other during the drainage process, avoiding poor or excessive drainage in some areas due to uneven pressure, thereby improving gas drainage efficiency and ensuring that the underground gas concentration is within a safe range.

[0055] This operation also laid a good foundation for subsequent modifications and normal operation, reduced the probability of failures caused by pressure issues, reduced maintenance costs and downtime, and improved the overall economic benefits and safety of coal mine gas extraction.

[0056] In some embodiments provided in this application, before connecting the temporary extraction branch, the method further includes: setting up a local ventilation device and an emergency extraction pump near the borehole to be modified; the inlet of the emergency extraction pump is connected in parallel with the temporary extraction branch through a three-way valve; when the gas concentration at the borehole exceeds a first set threshold, the local ventilation device is automatically activated; when the gas concentration exceeds a higher second set threshold, the three-way valve is automatically switched and the emergency extraction pump is activated to introduce the gas into the emergency discharge pipeline.

[0057] In this embodiment, a local ventilation device and an emergency extraction pump are installed near the borehole opening to provide dual safety protection. When the methane concentration at the opening exceeds a first preset threshold, the local ventilation device automatically activates, promptly diluting the local methane concentration and preventing further accumulation, thus reducing the risk of accidents such as methane explosions and creating a relatively safe working environment for underground workers. When the methane concentration exceeds a higher second preset threshold, and the situation becomes more critical, the system automatically switches the three-way valve and activates the emergency extraction pump to quickly guide the methane into the emergency discharge pipeline, preventing a large accumulation of methane near the opening and avoiding serious safety accidents, effectively protecting personnel safety and coal mine production safety.

[0058] In terms of emergency response capabilities, this solution improves the speed and efficiency of handling abnormal gas outbursts. The automated control mechanism requires no manual intervention, enabling it to react immediately and take swift and effective measures to control gas concentration, reduce the likelihood of accidents, and minimize accident losses.

[0059] In terms of the overall transformation process, these measures provide a safe premise for the subsequent connection of temporary drainage branches and transformation work, ensuring that the transformation process is carried out in a safe and controllable environment, which helps to improve the smooth progress and success rate of the transformation of the entire coal mine gas drainage pipeline network system.

[0060] In some embodiments provided in this application, before connecting the temporary extraction branch, the method further includes: preparing a corresponding number of temporary extraction branches, monitoring process pipe sections, and transition pipe fittings for parallel connection between the temporary extraction branches and the main extraction pipeline, based on the number of boreholes in the drilling site to be modified; wherein, the transition pipe fittings include a butterfly valve, a transparent PVC steel wire hose, a first short section pipe and a second short section pipe, the first short section pipe is provided with multiple branch interfaces matching the number of boreholes, and each branch interface is correspondingly provided with a ball valve.

[0061] In this embodiment, by pre-fabricating a first short section of pipeline with multiple branch interfaces according to the number of boreholes, and directly assembling ball valves to each interface, no temporary measurement, cutting, or welding is required on-site, allowing for rapid assembly. This transforms the traditionally complex pipeline connection work into standardized interface docking, shortening the time required to establish a temporary extraction system and ensuring that the main extraction system can be restored to normal extraction status as quickly as possible.

[0062] Using transparent PVC steel wire hoses as temporary gas delivery channels allows operators to directly observe the airflow within the pipes and detect any abnormalities such as liquid water accumulation or coal dust blockage. This intuitive visual monitoring enables early detection and handling of pipeline faults, avoiding safety risks such as extraction failure and localized gas accumulation caused by poor flow in temporary pipelines, and enhancing the safety redundancy of the entire renovation process.

[0063] Ball valves are independently configured at each branch interface of the first short section of pipeline, forming independent opening and closing control nodes and coarse flow adjustment control nodes for multiple temporary extraction branches. Combined with the butterfly valves on the main pipeline, a multi-level control system of main valve + branch valves is formed. Operators can make differentiated adjustments or isolate maintenance on the extraction status of each borehole according to actual needs, realizing refined management of the temporary extraction system and ensuring the stability and controllability of the extraction effect.

[0064] In some embodiments provided in this application, the main extraction pipeline and multiple extraction branches are connected by a gas collection box, and the gas collection box is connected to the multiple extraction branches through a manifold. The method further includes: after closing the main control valve of the main extraction pipeline and the branch control valve of the extraction branch to be modified, installing a first short section pipeline and a butterfly valve at the interface between the gas collection box and the manifold, and ensuring that the butterfly valve is in the closed state; cutting off the manifold on the side of the butterfly valve near the manifold; and after the original extraction branch is modified, connecting the cut-off manifold through a second short section pipeline.

[0065] In this embodiment, after closing the main control valve and the branch control valve, a first short section of pipeline with a butterfly valve is installed at the outlet of the gas collection box to create a dedicated and reliable mechanical isolation point. This allows subsequent cutting of the manifold to be carried out in a fully controlled inertial environment, reducing the risk of gas leakage. Moreover, the presence of the butterfly valve provides a clear control node for subsequent system restoration, achieving reversible and precise control of safe isolation.

[0066] The traditional pipeline modification process is transformed into a standardized procedure of "prefabricated interface installation - original pipe cutting - new pipeline connection". The addition of the first short pipe section, along with the reservation of monitoring or adjustment interfaces, provides the hardware foundation for subsequent functional expansion such as the installation of sensors and regulating valves, enabling system upgrades to be achieved simultaneously with a single isolation modification, thereby improving the overall efficiency of the operation.

[0067] By connecting the severed manifold to a pre-designed second short section of pipe, the sealing, coaxiality, and flow performance of the pipeline after restoration are ensured. This allows the modified pipeline system to not only reliably restore its original function, but also to achieve better flow efficiency and long-term sealing performance than traditional maintenance methods, thus ensuring the continuous and stable operation of the extraction system.

[0068] In practical applications, the process of modifying the original extraction branch also includes a dynamic pressure balancing step: pressure sensors are installed at the inlet ends of the temporary extraction branch and the original extraction branch respectively; the pressure difference between the two ends is monitored and compared in real time, and the inlet pressure of the temporary branch is kept basically consistent with that of the original branch by adjusting the regulating valve on the temporary extraction branch, so as to prevent abnormal gas outburst in the borehole due to sudden pressure changes.

[0069] In this embodiment, by installing pressure sensors at the inlet ends of the temporary and original extraction branches, the pressure difference can be monitored and compared in real time, allowing for precise control of the pressure status of the two branches. Timely adjustment of the regulating valve on the temporary extraction branch ensures that the inlet pressures of both branches are essentially the same, effectively preventing abnormal gas outbursts caused by sudden pressure changes. This avoids excessive local gas concentrations due to large gas outbursts, reducing the probability of gas explosions, poisoning, and other safety accidents, and effectively protecting the lives of underground workers. Pressure balance ensures that gas is extracted at the expected flow rate and velocity, improving gas extraction efficiency, increasing gas resource recovery, and providing strong support for safe production and resource utilization in coal mines. Simultaneously, it reduces the impact of pressure issues on extraction equipment and pipelines, extending equipment lifespan.

[0070] After the original extraction branch is modified and before the temporary extraction branch is dismantled, the construction quality verification steps are also included: temporarily closing the temporary control valve and conducting trial extraction only through the modified original extraction branch; using sensors installed on the modified pipeline to monitor the extraction parameters and comparing them with historical data or preset standards before the modification; if the parameters meet the requirements, the subsequent recovery steps are executed; if they do not meet the requirements, the section is readjusted or modified until the verification is qualified.

[0071] In this embodiment, by briefly closing the temporary control valve and relying solely on the modified original extraction branch for trial extraction, the independent operational capability of the modified section can be accurately verified. By monitoring extraction parameters with sensors and comparing them with historical data or preset standards before the modification, it is possible to accurately determine whether the modification has achieved the expected results, promptly identify potential problems such as inadequate pipeline sealing or substandard extraction efficiency, and prevent the unqualified modification from being put into use, thus ensuring the quality of the modification. In terms of safety control, early verification of the modification quality can prevent abnormal gas extraction caused by modification problems, reduce the risk of safety accidents caused by gas accumulation, and create a safe working environment for underground workers. Successful verification on the first attempt allows for smooth execution of subsequent recovery steps, reducing repeated construction and debugging time, improving overall modification efficiency, reducing additional costs caused by unqualified modification, and ensuring that the coal mine gas extraction system returns to normal and efficient operation as quickly as possible.

[0072] After the sensor data is connected to the remote monitoring system, a dynamic adjustment step based on the monitoring data is also included: the remote monitoring system acquires carbon monoxide concentration, methane concentration and flow rate data in real time; when the methane concentration is detected to be lower than the set lower limit, an adjustment command is automatically generated to increase the extraction intensity of the temporary extraction branch through the adjustment module; when the carbon monoxide concentration is detected to be abnormally high, an alarm is automatically triggered and the location and time information of the branch are recorded for subsequent safety analysis.

[0073] In this embodiment, the remote monitoring system acquires real-time data on carbon monoxide concentration, methane concentration, and flow rate, forming a comprehensive safety monitoring network. When the carbon monoxide concentration rises abnormally, an alarm is automatically triggered, and the branch location and time information are recorded. This quickly alerts staff to potential safety hazards, providing crucial data for subsequent safety analysis and helping to take timely measures to prevent accidents such as fires. When the methane concentration is detected to be below the set lower limit, an adjustment command is automatically generated to increase the extraction intensity of the temporary extraction branch. This fully utilizes extraction capacity, avoids wasting gas resources due to insufficient extraction, and ensures that the underground gas concentration remains within a safe range. This dynamic adjustment mechanism allows the gas extraction system to be flexibly adjusted according to actual conditions, improving the accuracy and efficiency of extraction and ensuring the safe and stable operation of coal mine production.

[0074] When multiple extraction branches need to be modified sequentially, the process also includes a construction sequence optimization step based on flow network simulation: Before construction, a pipeline flow network model is established based on the gas flow rate, pipeline resistance, and main extraction pipeline capacity of each branch; the total flow rate and pressure fluctuation of the main extraction pipeline are calculated through model simulation under different branch modification sequences; the branch modification sequence with the least impact on the overall extraction stability of the system is selected, and temporary extraction branches are connected in sequence and modification work is carried out accordingly.

[0075] In this embodiment, a pipeline network model is established before construction based on the gas flow rate of each branch, pipeline resistance, and the capacity of the main drainage pipeline. By simulating the total flow rate and pressure fluctuations of the main drainage pipeline under different modification sequences, the impact of each sequence on the system can be accurately predicted. Selecting the construction sequence with the least impact on overall drainage stability can effectively avoid large fluctuations in the flow rate and pressure anomalies in the main drainage pipeline caused by the modification, ensuring that the gas drainage system can still operate stably during the modification period, maintaining the underground gas concentration within a safe range, and reducing the risk of safety accidents. A reasonable construction sequence reduces construction interruptions and repeated adjustments caused by system instability, enabling the modification operation to be carried out continuously and efficiently, shortening the overall modification period, reducing the impact of long-term modification on coal mine production, and improving the economic benefits of gas drainage modification work.

[0076] In a specific embodiment, this application provides a method for modifying a coal mine gas drainage pipeline system, the specific steps of which are as follows: (1) Preparatory work before the modification: For each drilling site with 7-10 boreholes, one main control valve and several meters of transparent PVC steel wire hose are uniformly configured on the main extraction pipeline; and a bypass assembly is pre-processed. Among them, the main control valve can be a butterfly valve, and the bypass assembly can be two short sections of pipeline, namely the first short section pipeline and the second short section pipeline. 7-10 independent valves are pre-welded on the first short section pipeline. The independent valves can be ball valves.

[0077] (2) During the renovation process: 1) First, briefly close the butterfly valve of the main extraction system and the ball valve and gate valve at each borehole outlet.

[0078] 2) Next, use transparent PVC steel wire hoses to connect to the ball valves at the outlet of each borehole one by one, and connect the other end of the PVC steel wire hoses to the ball valves that have been pre-welded on the first short section of the pipeline.

[0079] 3) Next, open the butterfly valve of the main extraction system. These three steps complete the "temporary diversion of the gas extraction path" for each borehole and establish the normal extraction operation of the pipeline system.

[0080] 4) Next, install a section of "wireless network monitoring process pipeline" at a suitable location in the borehole piping system of each borehole.

[0081] 5) Next, use the pre-processed second short section of pipe to connect with the previously disconnected pipe.

[0082] 6) Finally, after all 7-10 boreholes at each drilling site have been modified, the temporary "gas drainage path system" will be dismantled. In this way, the drainage system at each drilling site will be restored to its original state. Repeat the above process to complete the modification of all borehole pipeline systems at the four gas drainage drilling sites.

[0083] (3) Subsequent renovation work: 1) Install a carbon monoxide sensor for coal mine pipelines, a laser methane sensor for coal mine pipelines, and an intrinsically safe ultrasonic gas flow sensor for mining on each of the "wireless network monitoring process pipelines" in each borehole.

[0084] 2) Use blue monitoring transmission cables, with one end connected to various sensors on the "wireless network monitoring process pipeline" of each borehole, and the other end connected to the power supply box of the monitoring substation.

[0085] 3) Finally, each drilling site connects and uses wireless network communication technology to transmit data to the online monitoring and intelligent control platform for gas extraction.

[0086] In practical applications, four negative pressure gas drainage drilling sites require modification. Each site has 7-10 independent drainage boreholes, which are organically combined and connected using seamless steel pipes of different diameters, hoses, gate valves, butterfly valves, flanges, gas-water separators, and water drainers to form an independent gas drainage system. Finally, the main drainage pipeline connects to the main drainage network in the roadway. The negative pressure power for each drilling site is provided by a surface gas drainage pumping station.

[0087] Figure 2 and Figure 3 The original state of the coal mine gas drainage pipeline system before its renovation; Figure 4 and Figure 5 The diagram shows the state after adding a temporary drainage branch to the coal mine gas drainage pipeline system; the black arrows in the diagram indicate the gas flow path. The coal mine gas drainage pipeline system includes the first seamless steel pipe 110, the first ball valve 120, the gate valve 130, the flange 140, the second ball valve 150, the third ball valve 152, the black PVC steel wire hose 160, the second seamless steel pipe 170, the first pipe section 172, the second pipe section 174, the transparent PVC steel wire hose 180, the first butterfly valve 190, the second butterfly valve 192, the first short section pipe 200, the second short section pipe 210, the observation pipe 220, and the gas collection box 230.

[0088] The specific modification steps are as follows: Step 1: Briefly close the first butterfly valve 190 and gate valve 130 in the main extraction system. Then, install the pre-fabricated first short pipe section 200 and the second butterfly valve 192 at the position shown in the dashed box (first pipe section 172). It is important to note that the second butterfly valve 192 is closed at this time. Next, disconnect the valve at the position shown in the dashed box (second pipe section 174). Then, use a transparent PVC flexible steel hose 180 to connect the first ball valve 120 and the second ball valve 150.

[0089] Step 2: Using another transparent PVC steel wire hose 180, connect sequentially to the control valves of other boreholes in a specific drainage drilling site and the other ball valves on the first short section of pipe 200. Typically, there are 7-10 boreholes in a drainage drilling site.

[0090] Step 3: After all boreholes in a given extraction drilling site are connected sequentially using transparent PVC steel wire hoses 180, the first butterfly valve 190 and the first ball valve 120 are opened in sequence. It is important to note that the gate valve 130 must remain closed at this time. Similarly, the third ball valve 152 must also remain closed.

[0091] After this operation, all boreholes in a certain gas extraction drilling site have "found alternative routes" to form new gas extraction and transportation channels, realizing the "temporary rerouting of the gas extraction path" for each borehole, and further ensuring the normal operation of the gas extraction pipeline network system. The above three steps can be completed in just one shift.

[0092] The subsequent modification process will not affect the normal gas extraction operations of all boreholes within the drilling site.

[0093] Step 4: Install the manufacturer's custom-made observation conduit 220 on each drilled hole. This special observation conduit 220 is officially called a "Wireless Network Monitoring Process Conduit" and is DN100mm in size. This observation conduit 220 has multiple interfaces for subsequent installation of various sensors.

[0094] It should be noted that gate valve 130 must be closed before installing each observation pipeline 220. Step 4 of the modification process is slightly more complicated and takes longer. However, the modification will not affect the normal gas extraction operation of each borehole, and the gas concentration will not exceed the limits stipulated by national laws and regulations.

[0095] Step 5: After all 7-10 boreholes in a drilling site have been modified according to the above steps, connect the second short section pipe 210 to the position shown in the second pipe section 174. Further, remove all transparent PVC steel wire hoses 180 from the drilling site. However, the second butterfly valve 192 can be retained and not removed; it can function effectively to control the piping system in case of other modification tasks.

[0096] Step 6: After completing all five steps above, open the gate valve 130 and the second butterfly valve 192 in sequence, while closing the first ball valve 120.

[0097] By following these six steps, the transformation of the extraction pipeline system for all boreholes in a drilling site can be completed.

[0098] Afterwards, following the above operating procedures, the other three extraction drilling sites were modified.

[0099] The core principle of the coal mine gas drainage pipeline system modification method provided in this application is as follows: Before modifying the drainage pipeline system, the gas drainage path of each independent borehole drainage system in each drilling site needs to be temporarily rerouted to connect it to the main drainage pipeline system to form a temporary closed loop. Subsequently, the borehole pipelines of each drilling site are modified one by one in sequence. After all borehole modifications are completed, the temporary drainage system is restored to the original drainage pipeline system.

[0100] In terms of practicality: Verified through actual engineering applications, this technology successfully overcomes the three major drawbacks of traditional modification methods. First, it does not affect the continuous operation of the extraction system; second, by constructing a temporary closed-loop extraction channel for each borehole, it eliminates the risk of gas exceeding limits; and third, the operation process is simple and efficient, significantly saving manpower and time costs, and possessing outstanding practical value.

[0101] In terms of novelty: No technology identical to this process has been found to be applied to the renovation project of the extraction drilling site in the coal mine, so it has obvious novelty.

[0102] In terms of innovation: This process innovatively utilizes existing facilities at the drilling site and uses DN25 transparent PVC steel wire hoses for connection to temporarily construct an independent gas extraction path for each extraction borehole, realizing "temporary diversion of the gas extraction channel". This ensures the continuous and stable operation of the entire pipeline system during the renovation, demonstrating significant technical innovation.

[0103] The key innovation of this method lies in constructing an independent closed-loop system through temporary rerouting, ensuring uninterrupted gas extraction during the modification period. Specific component replacement solutions include: the core component, the transparent PVC steel wire hose, can be replaced with a high-negative-pressure resistant hose of other sizes with the same performance; the second butterfly valve can be replaced with a gate valve; and the ball valve can be replaced with other valve types that meet the operating conditions, achieving flexible adaptation while ensuring system airtightness and negative pressure tolerance.

[0104] In this application, the term "multiple" refers to two or more unless otherwise expressly defined. The terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0105] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0106] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for upgrading a coal mine gas drainage pipeline network system, wherein the coal mine gas drainage pipeline network system includes a main drainage pipeline and multiple drainage branch pipelines, characterized in that, The method is used to upgrade and modify the target gas extraction branch while maintaining continuous gas extraction, and includes the following steps: Close the main control valve of the main extraction pipeline and the branch control valve of the extraction branch to be modified. A temporary extraction branch is connected between the branch control valve and the main extraction pipeline to form a temporary extraction channel in parallel with the original extraction branch, and the main control valve and the temporary control valve on the temporary extraction branch are opened. While the temporary extraction branch continues extraction, the original extraction branch is modified. After the original extraction branch is modified, the branch control valve is opened, the temporary control valve is closed, and the temporary extraction branch is dismantled, switching the gas extraction to the modified extraction branch.

2. The method for upgrading a coal mine gas drainage pipeline system according to claim 1, characterized in that, The main extraction pipeline is pre-installed with a connection structure for connecting the temporary extraction branch. The connection structure is a prefabricated bypass assembly. The bypass assembly has multiple branch interfaces integrated on its pipe wall, and each branch interface is equipped with an independent valve.

3. The method for upgrading a coal mine gas drainage pipeline system according to claim 2, characterized in that, The connection to the temporary extraction branch includes: A transparent PVC steel wire hose is used to connect the branch control valve to a selected branch interface.

4. The method for upgrading a coal mine gas drainage pipeline system according to claim 1, characterized in that, The modification and construction of the original extraction branch includes: A monitoring process pipe section equipped with multiple sensor interfaces was connected to the original extraction branch; Install the sensor on the sensor interface and connect the sensor data to the remote monitoring system; The sensor includes at least one of a carbon monoxide sensor, a laser methane sensor, and an ultrasonic gas flow sensor.

5. The method for upgrading a coal mine gas drainage pipeline system according to claim 1, characterized in that, The method further includes the following steps during the connection of temporary extraction branches: An adjustment module is installed on the temporary extraction branch, the adjustment module including an adjustment valve and a flow meter; By adjusting the opening of the regulating valve, the gas flow rate through the temporary extraction branch is matched with the target extraction flow rate.

6. The method for upgrading a coal mine gas drainage pipeline system according to claim 5, characterized in that, After opening the main control valve and the temporary control valve, and before the temporary extraction branch is officially put into operation, the following preparation and verification steps are also included: Inert gas or compressed air is injected into the temporary extraction branch to replace the gas, and the gas concentration is monitored by a gas concentration sensor to confirm that the gas concentration in the pipe is below the safety threshold. Open the temporary control valve, monitor the flow rate using a flow meter installed on the temporary extraction branch, and adjust the regulating valve on the temporary extraction branch to control the flow rate within the target extraction flow rate range.

7. The method for upgrading a coal mine gas drainage pipeline system according to claim 6, characterized in that, The commissioning preparation and verification steps also include: monitoring and adjusting the inlet pressure of the temporary extraction branch so that the difference between the inlet pressure of the temporary extraction branch and the inlet pressure of the original extraction branch in the closed state is less than a set value.

8. The method for upgrading a coal mine gas drainage pipeline system according to claim 1, characterized in that, Before connecting the temporary extraction branch, the method further includes: A local ventilation device and an emergency extraction pump are installed near the borehole to be modified; the inlet of the emergency extraction pump is connected in parallel with the temporary extraction branch through a three-way valve. When the gas concentration at the orifice exceeds the first set threshold, the local ventilation device is automatically activated; When the gas concentration exceeds a higher second set threshold, the three-way valve is automatically switched and the emergency extraction pump is started to introduce the gas into the emergency discharge pipeline.

9. The method for upgrading a coal mine gas drainage pipeline system according to claim 1, characterized in that, Before connecting the temporary extraction branch, the method further includes: Based on the number of boreholes in the drilling site to be modified, prepare a corresponding number of temporary extraction branches, monitoring process pipe sections, and transition pipes for parallel connection between the temporary extraction branches and the main extraction pipeline. The transition fittings include a butterfly valve, a transparent PVC steel wire hose, a first short section pipe, and a second short section pipe. The first short section pipe is provided with multiple branch interfaces that match the number of boreholes, and each branch interface is provided with a corresponding ball valve.

10. The method for upgrading a coal mine gas drainage pipeline system according to claim 9, characterized in that, The main extraction pipeline and multiple extraction branches are connected and converged through a gas collection box, which is connected to the multiple extraction branches through a manifold. The method further includes: After closing the main control valve of the main extraction pipeline and the branch control valve of the extraction branch to be modified, install the first short section pipeline and the butterfly valve at the interface between the gas collecting box and the manifold, and ensure that the butterfly valve is in the closed state; cut off the manifold on the side of the butterfly valve near the manifold. After the original extraction branch is modified, the severed manifold is connected through the second short section of the pipeline.

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