Shale gas pressurization system for improving lifting capacity of effective well
By adding a single-well membrane nitrogen lift reserve port and control unit to the gas injection port of the gas well casing, and using high-pressure nitrogen generated by the membrane nitrogen generator as the pilot gas, the problem of gas wells with severe liquid accumulation that is difficult to lift and open using traditional methods has been solved, achieving efficient gas well lifting and production improvement.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHINA PETROLEUM & CHEMICAL CORP
- Filing Date
- 2025-06-25
- Publication Date
- 2026-05-19
AI Technical Summary
Existing technologies are insufficient to effectively pump shale gas wells with severe fluid accumulation or complex geological conditions. Traditional compressors have poor gas injection performance, and nitrogen gas lift systems are complex and costly. There is a lack of efficient solutions that flexibly combine compressors and nitrogen gas lift.
A single-well membrane nitrogen lift port is added to the gas injection port of the gas well casing. High-pressure nitrogen is generated by the membrane nitrogen generator as a pilot gas. When the compressor cannot lift the gas, the gas lift is performed. Combined with the compressor, the liquid is continuously discharged. The gas injection function is automatically switched by the control unit.
It improves the lifting and circulation efficiency of gas wells, simplifies equipment complexity and cost, is applicable to various geological conditions and liquid accumulation situations, and significantly increases gas well production and economic benefits.
Smart Images
Figure CN224260322U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of shale gas pressurization technology, specifically to a shale gas pressurization system for improving the lifting and circulation capacity of effective wells. Background Technology
[0002] Shale gas, as an important unconventional natural gas resource, has seen rapid development in its extraction technology in recent years. Gas lift is a commonly used production enhancement technique in shale gas extraction. It involves injecting high-pressure gas into the well to help expel liquid from the wellbore, thereby reducing bottomhole back pressure and increasing gas production. However, in actual production, some wells, due to complex geological conditions or severe wellbore fluid accumulation, often cannot be effectively lifted and energized simply by relying on traditional booster injection, resulting in well production failing to meet expectations.
[0003] Currently, the commonly used gas lift enhancement methods in shale gas extraction mainly include the following: Traditional compressor injection: High-pressure air or natural gas is injected into the well casing through a surface compressor to help remove liquid from the wellbore. However, this method is often ineffective for wells with severe liquid accumulation or complex geological conditions, making it difficult to effectively lift the well. Continuous gas lift: High-pressure gas is continuously injected to achieve continuous removal of liquid from the wellbore. While this method improves lifting capacity to some extent, it still has limitations for some difficult-to-lift wells. Nitrogen gas lift: Nitrogen is used as the injection gas. Due to its lower density, nitrogen can more effectively reduce the density of liquid in the wellbore, thereby improving lifting capacity. However, existing nitrogen gas lift systems typically require complex equipment and piping and are difficult to integrate effectively with existing compressor systems.
[0004] The above technical solutions have the following problems in practical applications: relying solely on compressor gas injection is difficult to effectively lift gas wells with severe liquid accumulation; nitrogen gas lift systems are complex and costly, making large-scale promotion difficult; therefore, existing technologies lack an efficient solution that can flexibly combine compressors and nitrogen gas lift. Utility Model Content
[0005] Based on this, this application provides a shale gas booster system to enhance the lifting capacity of the affected well. This system can flexibly combine a compressor and nitrogen gas lift to improve the lifting capacity of the affected well. By adding a single-well membrane-based nitrogen gas lift port to the casing injection port of each gas well, when the compressor cannot lift the well, the well can first be opened using high-pressure membrane-based nitrogen gas lift, and then high-pressure gas from the booster compressor can be introduced for continuous drainage, thereby effectively improving the lifting capacity of the gas well.
[0006] This application provides a shale gas pressurization system for enhancing the effective well lift-through capacity, comprising:
[0007] One or more single-well membrane nitrogen lift gas lift ports, membrane nitrogen generation equipment, gas injection pipelines, and compressors;
[0008] One of the single-well membrane nitrogen lift-up reserved ports is set on the gas injection port of the gas well casing of the effective well, and is connected to the membrane nitrogen generation equipment and the compressor through gas injection pipelines respectively; the single-well membrane nitrogen lift-up reserved port serves as a connection channel between the membrane nitrogen generation equipment and the gas well casing. In the case that the gas well cannot be lifted by the compressor, the high-pressure nitrogen generated by the membrane nitrogen generation equipment is injected into the gas well casing through the single-well membrane nitrogen lift-up reserved port to lift the effective well;
[0009] The compressor is connected to one or more of the single-well membrane nitrogen lift pre-reserved ports via an injection pipeline to provide high-pressure gas.
[0010] In some embodiments, the reserved port for single-well membrane nitrogen lift includes a valve, a tubing coupling, and a plug;
[0011] The valve is connected to the gas injection port of the gas well casing;
[0012] The tubing coupling is connected to the gas injection port of the valve and the gas well casing respectively. The tubing coupling serves as a pipeline interface to transport the high-pressure nitrogen generated by the membrane nitrogen generator to the gas well casing.
[0013] The plug is connected to the tubing coupling. In the non-gas lift stage or when the single-well membrane nitrogen gas lift reserved port is not used, the plug seals the end of the pipeline.
[0014] In some embodiments, the gas injection pipeline includes a first branch pipeline and a second branch pipeline; the membrane nitrogen generator is connected to the single-well membrane nitrogen lift reserved port through the first branch pipeline; and the compressor is connected to the single-well membrane nitrogen lift reserved port through the second branch pipeline.
[0015] In some embodiments, the shale gas pressurization system further includes a control unit, which is communicatively connected to the membrane nitrogen generator, the valve of each single-well membrane nitrogen lift port, and the compressor. The control unit is configured to control the membrane nitrogen generator, the gas injection function, and the opening and closing status of the valve of each single-well membrane nitrogen lift port.
[0016] In some embodiments, the control unit is configured to automatically switch the gas injection function of the membrane nitrogen generator and the compressor based on the well's pumping status and drainage effect.
[0017] In some embodiments, the operating pressure of the membrane nitrogen generator is less than or equal to 35 MPa.
[0018] In some embodiments, the membrane nitrogen generator is a membrane nitrogen lift vehicle.
[0019] In some embodiments, the control unit is further configured to preferentially start the membrane nitrogen generator for gas lift.
[0020] In some embodiments, the control unit is further configured to control the gas injection mode performed by the compressor when the effective well is energized.
[0021] In some embodiments, the tubing coupling is fixed to the gas injection port of the gas well casing via a threaded connection.
[0022] Compared with existing technologies, the beneficial effects of this application are: utilizing high-pressure nitrogen generated by a membrane nitrogen generator as a pilot gas can more effectively lift gas wells with severe liquid accumulation, solving the problem of difficulty in lifting wells using traditional compressor-based gas injection, and improving the lifting efficiency of the affected well. Compared with traditional nitrogen gas lift systems, the shale gas pressurization system provided in this application reduces equipment complexity and cost through pre-reserved ports, resulting in higher economic efficiency. This system is also applicable to gas wells with various geological conditions and liquid accumulation situations, exhibiting wide applicability and significantly improving gas well production and economic benefits. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of the connection of a shale gas booster system for enhancing the lifting and circulation capacity of an effective well, as provided in an embodiment of this application.
[0024] Figure 2 This is a schematic diagram of the structure of the reserved port for single-well membrane nitrogen lift provided in the embodiments of this application.
[0025] Figure reference numerals: 10 Shale gas pressurization system; 11 Single-well membrane nitrogen lift gas lift reserved port; 12 Membrane nitrogen production equipment; 13 Gas injection pipeline; 14 Compressor; 15 Gas well casing gas injection port; 111 Valve; 112 Tubing coupling; 113 Plug. Detailed Implementation
[0026] The present application will now be described in further detail with reference to experimental examples and specific embodiments. However, this should not be construed as limiting the scope of the subject matter of the present application to the following embodiments. All technologies implemented based on the content of the present application fall within the scope of protection of the present application.
[0027] Unless otherwise specified, the terms "upper," "lower," "left," "right," "center," "inner," "outer," and "side" used in the description of specific embodiments of this application to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is usually placed during use. These terms are merely for the purpose of facilitating the description of the solution in this application or simplifying the description in specific embodiments, so as to enable those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on this application.
[0028] In the description of the embodiments of this application, technical terms such as "first" and "second" only distinguish one entity or operation from another, and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary or secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.
[0029] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0030] Please refer to Figure 1 , Figure 1 This is a connection diagram of a shale gas booster system for enhancing the lift-up capacity of an effective well, provided in an embodiment of this application. The shale gas booster system 10 may include:
[0031] One or more single-well membrane nitrogen lift gas lift reserved ports 11, membrane nitrogen generation equipment 12, gas injection pipeline 13, and compressor 14.
[0032] One of the single-well membrane nitrogen lift-up port 11 is set on the gas injection port of the gas well casing of the effective well, and is connected to the membrane nitrogen generation equipment 12 and the compressor 14 through the gas injection pipeline 13 respectively. The single-well membrane nitrogen lift-up port 11 serves as a connection channel between the membrane nitrogen generation equipment 12 and the gas well casing. When the compressor 14 cannot lift the gas well, the high-pressure nitrogen generated by the membrane nitrogen generation equipment 12 is injected into the gas well casing through the single-well membrane nitrogen lift-up port 11 to lift the effective well.
[0033] The compressor 14 is connected to one or more single-well membrane nitrogen lift ports 11 via the gas injection line 13 to provide high-pressure gas.
[0034] The number of single-well membrane nitrogen lift pre-reserved ports 11 is determined according to the number of affected wells. Each affected well's gas well casing injection port will be equipped with one single-well membrane nitrogen lift pre-reserved port 11. The membrane nitrogen generation device 12 can be one or multiple. One membrane nitrogen generation device 12 can provide high-pressure nitrogen to one affected well or to multiple affected wells.
[0035] In this embodiment, 10 effective wells are used as an example for explanation. The effective wells are numbered 1-10. Since there are 10 effective wells, a single-well membrane nitrogen lift reserve port 11 is provided on the gas injection port of the gas well casing of each effective well. Each single-well membrane nitrogen lift reserve port 11 is connected to the membrane nitrogen generation equipment 12 and the compressor 14 through a gas injection pipeline.
[0036] In this embodiment, the single-well membrane nitrogen lift port 11 provides an access point for the membrane nitrogen lift, and the switching between nitrogen and compressor gas 14 is controlled by a valve. The membrane nitrogen generator 12 can produce high-pressure nitrogen as a pilot gas to aid in lifting the gas well. The compressor 14 can provide high-pressure gas for continuous liquid discharge, ensuring stable production of the gas well. The gas injection line 13 introduces the high-pressure nitrogen and compressor gas 14 into the gas well to realize the gas lift function.
[0037] Optionally, the single-well membrane nitrogen lift pre-reserved port 11 consists of a valve 111, a tubing coupling 112, and a plug 113. Please refer to [link / reference]. Figure 2 , Figure 2 This is a schematic diagram of a pre-reserved port for a single-well membrane nitrogen lift system provided in this embodiment. Valve 111 can be a PN35 / DN65 manual flat valve, where PN35 indicates a nominal pressure rating of 35 bar; DN65 indicates a nominal diameter of 65 mm. The tubing coupling 112 can be threadedly fixed to the gas injection port of the gas well casing. The tubing coupling 112 and plug 113 can be a 2 7 / 8” variable threaded short connector tubing coupling 112 and a threaded plug. 2 7 / 8” refers to a pipe outer diameter of 2.875 inches. A short connector is a short pipe fitting, used for pipe diameter changes, turns, or transition connections. A variable threaded short connector refers to a short connector with different thread specifications at both ends. A threaded plug is a plug with external threads used to seal pipe or equipment interfaces to prevent gas or liquid leakage.
[0038] Valve 111 is connected to the gas injection port 15 of the gas well casing; by switching valve 111, the gas source, such as membrane nitrogen generator 12 or compressor 14, is selected, and the high-pressure gas flow rate injected into the gas well is adjusted.
[0039] The tubing coupling 112 is connected to the gas injection port of the valve 111 and the gas well casing respectively. The tubing coupling 112 serves as a pipeline interface to transport the high-pressure nitrogen generated by the membrane nitrogen generator 12 to the gas well casing. The plug 113 is connected to the tubing coupling 112. In the non-gas lift stage or when the single-well membrane nitrogen gas lift reserved port 11 is not used, the plug 113 seals the end of the pipeline.
[0040] Optionally, the gas injection pipeline 13 includes a first branch pipeline and a second branch pipeline; the membrane nitrogen generator 12 is connected to the single-well membrane nitrogen lift reserved port 11 through the first branch pipeline; and the compressor 14 is connected to the single-well membrane nitrogen lift reserved port 11 through the second branch pipeline.
[0041] Optionally, the membrane nitrogen generator 12 can be a membrane nitrogen gas lift vehicle, and the working pressure of the membrane nitrogen generator 12 is less than or equal to 35 MPa.
[0042] The shale gas boosting system provided in this application embodiment may further include a control unit, which may be an independent controller or a calculator. The control unit is communicatively connected to the membrane nitrogen generator 12, the valve 111 of each single-well membrane nitrogen lift port 11, and the compressor 14. The control unit is configured to control the gas injection function of the membrane nitrogen generator 12 and the valve 111 of each single-well membrane nitrogen lift port 11. The control unit may be configured to automatically switch the gas injection function of the membrane nitrogen generator 12 and the compressor 14 according to the lift status and drainage effect of the gas well, prioritizing the activation of the membrane nitrogen generator 12 for gas lift, and controlling the gas injection mode performed by the compressor 14 when the effective well is lifted.
[0043] Specifically, the workflow of the shale gas pressurization system provided in this application embodiment may include:
[0044] Preparations before gas well lift: Install a single-well membrane nitrogen lift pre-reserved port 11 at the gas injection port 15 of the gas well casing, including a valve 111, tubing coupling 112, and plug 113. Connect the outlets of the membrane nitrogen generator 12 and compressor 14 to the pre-reserved port through the gas injection line 13.
[0045] Membrane-generated nitrogen lift stage: When compressor 14 fails to effectively lift the ventilation well, the control unit opens valve 111 of the membrane nitrogen generator 12, and high-pressure nitrogen enters the well casing through injection line 13. Utilizing the low density of nitrogen, this helps lift the ventilation well and remove accumulated liquid from the wellbore.
[0046] Compressor injection stage: High-pressure gas supplied by compressor 14 enters the gas well through injection pipeline 13 for continuous liquid discharge, ensuring stable production of the gas well.
[0047] System Switching and Monitoring: The control unit automatically switches the gas injection function of membrane nitrogen generator 12 and compressor 14 based on the well's pumping and drainage status. Real-time monitoring of the well's production parameters ensures efficient and safe system operation.
[0048] In the above implementation process, using high-pressure nitrogen generated by the membrane nitrogen generator 12 as a pilot gas can more effectively lift gas wells with severe liquid accumulation, solving the problem of difficulty in lifting with traditional compressor injection and improving the lifting efficiency of the affected well. The automatic switching between membrane nitrogen lift and compressor injection is achieved through the control unit, simplifying the operation process and optimizing the production process, thereby improving production efficiency. Compared with traditional nitrogen lift systems, the shale gas pressurization system provided in this application embodiment reduces equipment complexity and cost through pre-reserved ports and simple valve switching, resulting in higher economic efficiency. This system is also applicable to gas wells with various geological conditions and liquid accumulation, exhibiting wide applicability and significantly improving gas well production and economic benefits.
[0049] It should be understood that when the various modules of the system provided in the above embodiments are working, the division of each functional module in the above description is only used as an example. In actual applications, the above functions can be assigned to different functional modules as needed. That is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.
[0050] The functional modules in the above embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of the embodiments of this application.
[0051] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.
Claims
1. A shale gas pressurization system for enhancing the lifting and circulation capacity of effective wells, characterized in that, include: One or more single-well membrane nitrogen lift gas lift ports, membrane nitrogen generation equipment, gas injection pipelines, and compressors; One of the single-well membrane nitrogen lift-up reserved ports is set on the gas injection port of the gas well casing of the effective well, and is connected to the membrane nitrogen generation equipment and the compressor through gas injection pipelines respectively; the single-well membrane nitrogen lift-up reserved port serves as a connection channel between the membrane nitrogen generation equipment and the gas well casing. In the case that the gas well cannot be lifted by the compressor, the high-pressure nitrogen generated by the membrane nitrogen generation equipment is injected into the gas well casing through the single-well membrane nitrogen lift-up reserved port to lift the effective well; The compressor is connected to one or more of the single-well membrane nitrogen lift pre-reserved ports via an injection pipeline to provide high-pressure gas.
2. The shale gas pressurization system according to claim 1, characterized in that, The reserved port for single-well membrane nitrogen lift includes a valve, tubing coupling, and plug; The valve is connected to the gas injection port of the gas well casing; The tubing coupling is connected to the gas injection port of the valve and the gas well casing respectively, and the tubing coupling serves as a pipeline interface; The plug is connected to the tubing coupling. In the non-gas lift stage or when the single-well membrane nitrogen gas lift reserved port is not used, the plug seals the end of the pipeline.
3. The shale gas pressurization system according to claim 1, characterized in that, The gas injection pipeline includes a first branch pipeline and a second branch pipeline; the membrane nitrogen generator is connected to the reserved port of the single-well membrane nitrogen lift through the first branch pipeline; the compressor is connected to the reserved port of the single-well membrane nitrogen lift through the second branch pipeline.
4. The shale gas pressurization system according to claim 1, characterized in that, The shale gas pressurization system also includes a control unit, which is communicatively connected to the membrane nitrogen generator, the valve of each single-well membrane nitrogen lift port, and the compressor. The control unit is configured to control the gas injection function of the membrane nitrogen generator and the opening and closing status of the valve of each single-well membrane nitrogen lift port.
5. The shale gas pressurization system according to claim 4, characterized in that, The control unit is configured to automatically switch the gas injection function of the membrane nitrogen generator and the compressor based on the well's pumping and drainage status.
6. The shale gas pressurization system according to claim 4 or 5, characterized in that, The control unit is also configured to prioritize starting the membrane nitrogen generator for gas lift.
7. The shale gas pressurization system according to claim 6, characterized in that, The control unit is also configured to control the gas injection mode performed by the compressor when the effective well is energized.
8. The shale gas pressurization system according to claim 1, characterized in that, The working pressure of the membrane nitrogen generator is less than or equal to 35 MPa.
9. The shale gas pressurization system according to claim 1, characterized in that, The membrane nitrogen generator is a membrane nitrogen airlift vehicle.
10. The shale gas pressurization system according to claim 2, characterized in that, The tubing coupling is fixed to the gas injection port of the gas well casing via a threaded connection.