Method for establishing high-yield mode of coal-bed gas well

Abstract

The invention provides a method for establishing a coal-bed gas well high-yield mode, which comprises the following steps of: (1) designing a coal-bed gas well according to geological conditions and reservoir characteristics of a region where coal-bed gas resources are located; (2) adjusting a fracturing technology and a well completion technology; (3) changing the physical and chemical environments of the coal-bed gas well through a manual intervention technology; and (4) monitoring production parameters of the coal-bed gas well through a monitoring system, analyzing a monitoring result, and adjusting a production mode. The method can effectively improve the production efficiency and economic benefits of the coal-bed gas, improve the safety of the production process, protect the surrounding ecological environment and ensure the normal production of the coal-bed gas well.

Description

Technical Field

[0001] The invention belongs to the field of coalbed methane production and relates to a method for establishing a high-yield mode of a coalbed methane well. Background Art

[0002] Coalbed methane is an unconventional natural gas resource with a very large resource volume. Due to the unclear understanding of coalbed methane geological factors and engineering factors, the average daily production of coalbed methane wells varies greatly. In order to tap the internal production control factors of coalbed methane wells and improve the production capacity of coalbed methane wells, relevant researchers have conducted a lot of research work and achieved initial results. Traditional mining methods often cannot fully exploit low-permeability coalbed methane, resulting in low production and waste of resources. In addition, traditional mining methods lack effective monitoring and control methods, which are prone to safety hazards such as well leakage and bottom water. Summary of the invention

[0003] In order to solve the technical problems existing in the prior art, the present invention provides a method for establishing a high-yield mode of a coalbed methane well, which can effectively improve the production efficiency and economic benefits of coalbed methane, improve the safety of the production process, protect the surrounding ecological environment, and ensure the normal production of coalbed methane wells.

[0004] In order to achieve the above technical effects, the present invention adopts the following technical solutions:

[0005] The present invention provides a method for establishing a high-yield mode of a coalbed methane well, the method comprising:

[0006] (1) Design coalbed methane wells based on the geological conditions and reservoir characteristics of the area where the coalbed methane resources are located;

[0007] (2) Adjustments to fracturing technology and completion technology;

[0008] (3) Change the physical and chemical environment of coalbed methane wells through artificial intervention technology;

[0009] (4) Monitor the production parameters of coalbed methane wells through the monitoring system, analyze the monitoring results, and adjust the production methods.

[0010] As a preferred technical solution of the present invention, the design of the coalbed methane well in step (1) includes the well type, well diameter and completion method.

[0011] As a preferred technical solution of the present invention, the adjustment of the fracturing technology in step (2) includes: optimizing the components of the fracturing fluid to improve the viscosity and fluidity of the fracturing fluid; and adjusting the fracturing parameters to improve the fracturing effect.

[0012] As a preferred technical solution of the present invention, the fracturing fluid includes a viscosity enhancer and / or a degelling agent.

[0013] Preferably, the fracturing parameters include injection pressure, injection speed and injection volume.

[0014] As a preferred technical solution of the present invention, the completion technology adjustment in step (2) includes:

[0015] Use multi-stage isolation technology to ensure wellbore integrity and effective shielding;

[0016] Use bottom hole fluid control technology to reduce the impact of bottom hole water on coalbed methane production capacity;

[0017] Wellbore strengthening technology is used to improve the stability and pressure resistance of the wellbore.

[0018] As a preferred technical solution of the present invention, the multi-stage isolation technology includes casing isolation and cement isolation.

[0019] Preferably, the bottom hole fluid control technology includes artificial lifting and artificial lowering of the bottom hole water level.

[0020] Preferably, the wellbore strengthening technology includes wellbore lining and wellbore reinforcement.

[0021] As a preferred technical solution of the present invention, the coalbed methane well production parameters in step (4) include underground pressure, output and temperature.

[0022] As a preferred technical solution of the present invention, the establishment method of the monitoring system in step (4) includes:

[0023] Install underground pressure sensors and temperature sensors to monitor the underground pressure and temperature changes of coalbed methane wells in real time;

[0024] Equipped with production metering instruments to record the production and collection data of coalbed methane in real time;

[0025] Use data analysis and artificial intelligence technology to process and analyze monitoring data in real time, provide decision support and optimize control solutions;

[0026] Establish a remote monitoring system to remotely monitor and operate coalbed methane wells to improve production efficiency and safety.

[0027] As a preferred technical solution of the present invention, the method further includes step (5) of implementing regular wellbore inspection and maintenance.

[0028] As a preferred technical solution of the present invention, the wellbore inspection and maintenance includes:

[0029] Regularly inspect and clean the inside of the wellbore, repair air leaks, and remove impurities from the bottom water of the well;

[0030] repairing damaged sections of the wellbore;

[0031] Detect and maintain the integrity of the wellbore to ensure its stability and safety.

[0032] Preferably, the method for repairing a wellbore includes any one of well wall reinforcement, wellbore reinforcement and isolation layer repair, or a combination of at least two of them.

[0033] Compared with the prior art, the present invention has at least the following beneficial effects:

[0034] (1) The present invention provides a method for establishing a high-yield mode of a coalbed methane well, which improves the production capacity and recovery rate of low-permeability coalbed methane by optimizing the wellbore structure, increasing the wellbore area, improving the reservoir permeability and improving the fluid transmission path, thereby effectively improving the production efficiency and economic benefits of coalbed methane;

[0035] (2) The present invention provides a method for establishing a high-yield mode of a coalbed methane well. The method monitors the underground pressure, temperature changes, production and other parameters of the coalbed methane well in real time, detects abnormal conditions in time and takes corresponding measures to improve the safety of the production process;

[0036] (3) The present invention provides a method for establishing a high-yield mode for a coalbed methane well. The method maintains the stability and integrity of the wellbore through wellbore inspection and maintenance steps, prevents the occurrence of problems such as air leakage and bottom water, and ensures the normal production of the coalbed methane well. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic flow chart of the method for establishing a high-yield mode for a coalbed methane well provided in Example 1 of the present invention.

[0038] The present invention is further described in detail below. However, the following examples are only simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims. DETAILED DESCRIPTION

[0039] The technical solution of the present application is further described below through specific implementation methods.

[0040] A specific embodiment of the present invention provides a method for establishing a high-yield mode of a coalbed methane well, the method comprising:

[0041] (1) Design coalbed methane wells based on the geological conditions and reservoir characteristics of the area where the coalbed methane resources are located;

[0042] (2) Adjustments to fracturing technology and completion technology;

[0043] (3) Change the physical and chemical environment of coalbed methane wells through artificial intervention technology;

[0044] (4) Monitor the production parameters of coalbed methane wells through the monitoring system, analyze the monitoring results, and adjust the production methods.

[0045] In a specific embodiment of the present invention, the method for establishing a high-yield mode for a coalbed methane well further comprises conducting geological exploration in an area with potential coalbed methane resources to determine the best site for the coalbed methane well.

[0046] In one specific embodiment of the present invention, the method for selecting a coalbed methane well site comprises:

[0047] Analyze geological and geomorphological characteristics and select areas with complex underground structures and well-developed coal seams as potential site selection areas;

[0048] Conduct geological surveys, including geological drilling, core sampling and groundwater chemical analysis, to assess the abundance and recoverability of coalbed methane resources;

[0049] Seismic exploration technology is used to interpret underground structures and predict reservoirs to determine the best coalbed methane well site.

[0050] In a specific embodiment of the present invention, the step of analyzing geological and geomorphological characteristics may include conducting a comprehensive analysis of the surface landforms, geological structures, and groundwater levels, and selecting areas with higher coal seam development potential as potential site selection areas.

[0051] In a specific embodiment of the present invention, the geological survey step may further include a detailed investigation and evaluation of reservoir parameters such as coal seam thickness, burial depth, porosity and permeability to determine the abundance and recoverability of coalbed methane resources.

[0052] In a specific embodiment of the present invention, seismic exploration technology may include the collection and interpretation of seismic exploration data, and by analyzing seismic profiles and seismic inversion results, the distribution, thickness and connectivity of coalbed methane reservoirs are predicted to determine the optimal coalbed methane well site.

[0053] In a specific embodiment of the present invention, designing the well type, well diameter and completion method of a coalbed methane well according to geological conditions and reservoir characteristics includes the following steps:

[0054] Step 1: Assessment of geological and reservoir conditions: Geological surveys are first conducted to collect data on the thickness, depth, porosity, permeability and gas content of the coal seams.

[0055] Step 2: Design well type: Select the appropriate well type (vertical, inclined or horizontal well) based on geological data. The selected well type should maximize resource extraction and adapt to the complexity of the geological structure.

[0056] Step 3: Well diameter selection: Determine the well diameter size based on expected equipment requirements and production targets.

[0057] Step 4: Completion method design: Select the most suitable completion technology. For low permeability coal seams, use multi-stage fracturing technology to increase the extraction rate of coalbed methane.

[0058] In the present invention, the wellbore structure is optimized, the wellbore wall area is increased, the reservoir permeability is improved, and the fluid transmission path is improved. Specifically, the multi-stage isolation technology is adopted to improve the sealing and pressure resistance of the wellbore. The multi-stage isolation technology can effectively prevent cross-contamination between different layers by isolating the reservoir in sections, thereby optimizing the overall wellbore structure and ensuring that the coalbed methane is not affected by the bottom water or other layers of gas during its ascent in the wellbore.

[0059] In the present invention, the well type design of horizontal well or multi-branch well is selected to increase the contact area between the well wall and the coal seam. Horizontal well or multi-branch well effectively increases the area where coal bed methane can be mined by extending the length of the wellbore in the coal seam, thereby directly improving the recovery rate of coal bed methane.

[0060] In a specific embodiment of the present invention, the fracturing fluid may include a combination of a viscosity enhancer, a debonder and other additives to increase the viscosity, fluidity and stimulation effect of the fracturing fluid and improve the extraction efficiency of coalbed methane.

[0061] In one embodiment of the present invention, other additives may include corrosion inhibitors to protect the wellbore and underground equipment from corrosion by corrosive substances such as acids that may be contained in the fracturing fluid. Biocides to prevent scale from depositing on the wellbore and equipment, because the deposits will reduce the effective width of the cracks and affect the production of oil and gas. Friction reducers to reduce the flow resistance of the fracturing fluid in the wellbore.

[0062] In a specific embodiment of the present invention, changing the viscosity and rheology of the fracturing fluid by adjusting the specific compounds and ratios of the viscosifier, degelling agent and other additives is a conventional technique in the art and is not specifically limited herein.

[0063] In a specific embodiment of the present invention, the adjustment of the fracturing parameters may further include optimizing the viscosity, viscosity and flow rate of the injected liquid, and controlling the injection amount to achieve the best fracturing effect and coalbed methane production.

[0064] In a specific embodiment of the present invention, the multi-stage isolation technology may further include a casing cementing process and a cement isolation improvement to ensure the sealing and integrity of the wellbore and prevent problems such as gas leakage and well wall collapse.

[0065] In a specific embodiment of the present invention, the bottom hole fluid control technology may include realizing artificial regulation of the bottom hole water level through a bottom hole pump or other control device, thereby reducing the impact of bottom hole water on coalbed methane production capacity and increasing wellhead production.

[0066] In a specific embodiment of the present invention, the wellbore strengthening technology may further include the selection of wellbore lining materials and the optimization of construction technology, as well as the improvement of wellbore reinforcement technology, so as to improve the stability and pressure resistance of the wellbore.

[0067] In a specific embodiment of the present invention, the artificial intervention technology to change the physical and chemical environment of the coalbed methane well may further include acidification treatment, injecting hydrochloric acid or other types of acid to dissolve minerals in the coal seam.

[0068] In a specific embodiment of the present invention, underground pressure sensors and temperature sensors can be arranged at different depths in the wellbore to monitor the underground pressure and temperature changes of the coalbed methane well in real time, providing data support for optimization and regulation.

[0069] In a specific embodiment of the present invention, devices such as pressure sensors, temperature sensors and production metering instruments are all commonly used monitoring devices in the field. Their specific models can be selected according to the coalbed methane production needs and geological conditions, and are not further limited here.

[0070] In a specific embodiment of the present invention, data analysis and artificial intelligence technology may further include model building and predictive analysis of monitoring data, and use machine learning and data mining algorithms to achieve optimal control of parameters such as coalbed methane well production capacity, pressure and temperature.

[0071] In a specific embodiment of the present invention, the mathematical models used in data analysis are all commonly used mathematical models in the field, and can be selected according to calculation results and convergence requirements, and are not further limited here.

[0072] In a specific embodiment of the present invention, the algorithm can be further optimized through artificial intelligence technology, such as the support vector machine method, to improve the accuracy of prediction and regulation.

[0073] In a specific embodiment of the present invention, the internal inspection and cleaning of the wellbore may include using a drone or other inspection equipment to conduct a comprehensive inspection and cleaning of the inside of the wellbore to remove blockages and impurities to ensure the patency and normal operation of the wellbore.

[0074] In one specific embodiment of the present invention, repairing the damaged portion of the wellbore may include specific processes and material selection for well wall reinforcement, wellbore reinforcement and isolation layer repair to repair air and water leakage problems in the wellbore and ensure the integrity and safety of the wellbore.

[0075] In one specific embodiment of the present invention,

[0076] To better illustrate the present invention and facilitate understanding of the technical solution of the present invention, typical but non-limiting embodiments of the present invention are as follows:

[0077] Example 1

[0078] This embodiment provides a method for establishing a high-yield mode of a coalbed methane well, and the process is as follows: Figure 1 As shown, the method includes:

[0079] (1) Conduct geological exploration in areas with potential coalbed methane resources to determine the best coalbed methane well site;

[0080] Specifically, the geological and geomorphological characteristics are analyzed, and areas with complex underground structures and well-developed coal seams are selected as potential site selection areas;

[0081] Conduct geological surveys, including geological drilling, core sampling and groundwater chemical analysis, to assess the abundance and recoverability of coalbed methane resources;

[0082] Use seismic exploration technology to interpret underground structures and predict reservoirs to determine the best coalbed methane well locations;

[0083] (2) Design coalbed methane wells based on the geological conditions and reservoir characteristics of the area where the coalbed methane resources are located;

[0084] Specifically, designing the well type, well diameter and completion method of a coalbed methane well includes the following steps:

[0085] Step 1: Geological and reservoir condition assessment: First, geological exploration is carried out to collect data on the thickness, burial depth, porosity, permeability and gas content of the coal seam;

[0086] Step 2: Design well type: Select the appropriate well type (vertical, inclined or horizontal well) based on geological data. The selected well type should maximize resource extraction and adapt to the complexity of the geological structure;

[0087] Step 3: Well diameter selection: Determine the well diameter size based on expected equipment requirements and production targets;

[0088] Step 4: Completion method design: Select the most suitable completion technology. For low-permeability coal seams, use multi-stage fracturing technology to increase the extraction rate of coalbed methane;

[0089] (3) Adjust fracturing technology and completion technology;

[0090] Specifically, the fracturing fluid components are optimized to improve the viscosity and fluidity of the fracturing fluid; the fracturing fluid may include a combination of a viscosifier, a degelator, and other additives to improve the viscosity, fluidity, and stimulating effect of the fracturing fluid;

[0091] Adjusting fracturing parameters to improve fracturing effect; fracturing parameters include injection pressure, injection speed and injection volume; fracturing parameter adjustment further includes optimizing the viscosity, viscosity and flow rate of the injected liquid, as well as controlling the injection volume, to achieve the best fracturing effect and coalbed methane production;

[0092] Completion technology adjustments include:

[0093] Use multi-stage isolation technology, including casing isolation and cement isolation, to ensure wellbore integrity and effective shielding;

[0094] Use bottom hole fluid control technology, including artificial lifting and artificial lowering of the bottom hole water level, to reduce the impact of bottom hole water on coalbed methane production capacity;

[0095] Use wellbore strengthening technologies, including well lining and wellbore reinforcement, to improve wellbore stability and pressure resistance;

[0096] (4) Change the physical and chemical environment of coalbed methane wells through artificial intervention technology;

[0097] Specifically, through acidification, hydrochloric acid or other types of acid are injected to dissolve minerals in the coal seam;

[0098] (5) Monitor the production parameters of coalbed methane wells through the monitoring system, analyze the monitoring results, and adjust the production methods;

[0099] CBM well production parameters include underground pressure, production rate, and temperature;

[0100] The monitoring system can be established by:

[0101] Install underground pressure sensors and temperature sensors to monitor the underground pressure and temperature changes of coalbed methane wells in real time;

[0102] Equipped with production metering instruments to record the production and collection data of coalbed methane in real time;

[0103] Use data analysis and artificial intelligence technology to process and analyze monitoring data in real time, provide decision support and optimize control solutions;

[0104] Establish a remote monitoring system to remotely monitor and operate coalbed methane wells to improve production efficiency and safety;

[0105] (6) Implement regular wellbore inspection and maintenance;

[0106] Specifically, regularly inspect and clean the inside of the wellbore, repair air leaks in the well, and remove impurities from the water at the bottom of the well;

[0107] Repair the damaged part of the wellbore. The methods of repairing the wellbore include well wall reinforcement, wellbore reinforcement and isolation layer repair;

[0108] Detect and maintain the integrity of the wellbore to ensure its stability and safety.

[0109] The applicant declares that the present invention illustrates the detailed structural features of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed structural features, that is, it does not mean that the present invention must rely on the above-mentioned detailed structural features to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the components selected by the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0110] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0111] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0112] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A method for establishing a high-yield mode of a coalbed methane well, characterized in that: The method comprises: (1) Design coalbed methane wells based on the geological conditions and reservoir characteristics of the area where the coalbed methane resources are located; (2) Adjustments to fracturing technology and completion technology; (3) Change the physical and chemical environment of coalbed methane wells through artificial intervention technology; (4) Monitor the production parameters of coalbed methane wells through the monitoring system, analyze the monitoring results, and adjust the production methods.

2. The method according to claim 1, characterized in that The design of the coalbed methane well in step (1) includes the well type, well diameter and completion method.

3. The method according to claim 1, characterized in that Step (2) of adjusting the fracturing technology includes: optimizing the components of the fracturing fluid to increase the viscosity and fluidity of the fracturing fluid; and adjusting the fracturing parameters to improve the fracturing effect.

4. The method according to claim 2, characterized in that: The fracturing fluid includes a viscosity enhancer and / or a breaker; Preferably, the fracturing parameters include injection pressure, injection speed and injection volume.

5. The method according to claim 1, characterized in that The completion technology adjustment in step (2) includes: Use multi-stage isolation technology to ensure wellbore integrity and effective shielding; Use bottom hole fluid control technology to reduce the impact of bottom hole water on coalbed methane production capacity; Wellbore strengthening technology is used to improve the stability and pressure resistance of the wellbore.

6. The method according to claim 5, characterized in that The multi-stage isolation technology includes casing isolation and cement isolation; Preferably, the bottom hole fluid control technology includes artificial lifting and artificial lowering of the bottom hole water level; Preferably, the wellbore strengthening technology includes wellbore lining and wellbore reinforcement.

7. The method according to claim 1, characterized in that The coalbed methane well production parameters in step (4) include underground pressure, output and temperature.

8. The method according to claim 1, characterized in that The establishment method of the monitoring system in step (4) includes: Install underground pressure sensors and temperature sensors to monitor the underground pressure and temperature changes of coalbed methane wells in real time; Equipped with production metering instruments to record the production and collection data of coalbed methane in real time; Use data analysis and artificial intelligence technology to process and analyze monitoring data in real time, provide decision support and optimize control solutions; Establish a remote monitoring system to remotely monitor and operate coalbed methane wells to improve production efficiency and safety.

9. The method according to claim 1, characterized in that: The method also includes step (5) performing regular wellbore inspection and maintenance.

10. The method according to claim 9, characterized in that The wellbore inspection and maintenance includes: Regularly inspect and clean the inside of the wellbore, repair air leaks, and remove impurities from the bottom water of the well; repairing damaged sections of the wellbore; Detect and maintain the integrity of the wellbore to ensure its stability and safety; Preferably, the method for repairing a wellbore includes any one of well wall reinforcement, wellbore reinforcement and isolation layer repair, or a combination of at least two of them.

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