Sand prevention device for coal bed gas drainage and mining pipeline
By using spiral guide vanes and a multi-layer filter structure, the problem of traditional sand filtering devices being unable to effectively separate fine particles has been solved, achieving efficient separation and discharge of sand and coal powder in coalbed methane drainage pipelines and improving gas-liquid separation efficiency.
Patent Information
- Application Number
- CN202520427847.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-12
- Publication Date
- 2026-01-06
- Estimated Expiration
- 2035-03-12
AI Technical Summary
In existing technologies for traditional sand control devices, traditional sand filter pipes cannot effectively separate fine particles during coalbed methane extraction, leading to pipe wear and reduced gas-liquid separation efficiency.
It adopts a spiral guide vane and multi-layer filter structure design, and separates sand and coal powder by centrifugal force. Combined with multi-stage filter filtration, it achieves efficient separation and discharge of sand and coal powder.
It achieves efficient separation and discharge of sand and coal dust in coalbed methane drainage pipelines, reduces pipeline wear, and improves gas-liquid separation efficiency.
Smart Images
Figure CN223767480U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of pipeline sand prevention technology, and in particular to a sand prevention device for coalbed methane drainage pipelines. Background Technology
[0002] In the early stages of coalbed methane (CBM) production, the reservoir energy is high. If the production intensity is unreasonable, the production pressure differential is too large, and the fluid velocity increases, the possibility of sand production from the formation increases significantly. When CBM production enters the gas-water two-phase flow stage, the fluid viscosity increases rapidly, the liquid's sand-carrying and sand-suspending capacity is enhanced, the drag force during flow is greater, and the sand production increases accordingly. Especially in high-yield gas wells and wells with relatively fractured coal and rock structures in the target seam, the casing pressure, water production, and bottom hole flowing pressure of the gas well suddenly increase, the production parameters change significantly, the coal and rock have a weak sand-carrying capacity, and the high-speed gas flow generates a very high drag force, which can easily drag sand particles into the wellbore, leading to serious pump jamming, or even sand burying the tubing / coal seam, forcing the well to stop pumping for inspection, which seriously affects the gas production of a single well.
[0003] Workers install sand-blocking devices inside the coalbed methane drainage pipeline to intercept sand particles in the coalbed methane. When the sucker rod and tubular pump inside the oil pipe are operating, during coalbed methane drainage, the gas and liquid first enter the gas anchor through a perforated screen pipe. At this time, the perforated screen pipe can effectively filter and intercept sand and mud. Because traditional sand filter pipes only intercept sand particles through gaps or pores, they have problems such as being unable to effectively separate fine particles (such as coal dust) in the gas-liquid mixture, leading to pipeline wear and a decrease in gas-liquid separation efficiency. Utility Model Content
[0004] To address the aforementioned problems, this utility model proposes a sand-prevention device for coalbed methane drainage pipelines, thereby overcoming the shortcomings of existing methods.
[0005] To achieve the purpose of this utility model, the utility model is implemented through the following technical solution: a sand prevention device for coalbed methane drainage pipeline, including a filter cylinder, an inlet pipe joint on the outside of the filter cylinder, the inlet pipe joint being connected to the filter cylinder, and further including:
[0006] The end cap is detachably connected to the upper end of the filter cartridge. The upper end of the end cap is provided with a discharge pipe connector, which is fixedly connected to the end cap.
[0007] The guide tube is placed inside the filter cartridge and is fixedly connected to the lower end of the outlet pipe joint. The guide tube is connected to the outlet pipe joint.
[0008] Spiral guide vanes are fitted onto the outside of the guide tube, and the guide tube and spiral guide vanes are fixedly connected.
[0009] A multi-layer filter structure is fixedly connected to the lower end of the guide tube for multi-stage filtration of gas.
[0010] The flushing pipe is located at the lower end of the filter cartridge, and a one-way valve is provided at the connection between the flushing pipe and the filter cartridge.
[0011] A further improvement is made in that: the multi-layer filter structure includes a first conical filter, a second conical filter, a third conical filter, and a fourth conical filter. The first and second conical filters are both sleeved on the outside of the guide cylinder, and the second conical filter is placed below the first conical filter. Both the first and second conical filters are fixedly connected to the guide cylinder. The third and fourth conical filters are placed inside the guide cylinder, and the third conical filter is placed below the fourth conical filter. Both the third and fourth conical filters are fixedly connected to the guide cylinder.
[0012] The further improvement lies in the fact that the mesh count of the first, second, third, and fourth conical filters increases sequentially.
[0013] A further improvement is that a gap is provided between the spiral guide vanes, the first conical filter screen, the second conical filter screen, and the inner wall of the filter cylinder.
[0014] A further improvement is that the one-way valve includes a valve seat, which is fixedly connected to the lower end of the filter cartridge. A valve cavity is opened at the lower end of the valve seat, and a conical outlet is opened at the upper end of the valve seat. The conical outlet communicates with the valve cavity, and the valve cavity communicates with the flushing pipe. A spherical plug is provided inside the conical outlet, and the spherical plug cooperates with the conical outlet. A spring is provided inside the valve cavity, with one end of the spring fixedly connected to the spherical plug and the other end of the spring fixedly connected to the inner side wall of the valve cavity.
[0015] A further improvement is that: a first flange is provided at the lower edge of the end cover, and the first flange is fixedly connected to the end cover; a second flange is provided at the upper edge of the filter cylinder, and the second flange is fixedly connected to the filter cylinder; and multiple sets of fixing bolts for fixing the second flange are assembled on the first flange.
[0016] A further improvement is that sealing rings are provided on the facing sides of both the first flange and the second flange, and the two sets of sealing rings are fixedly connected to the first flange and the second flange respectively.
[0017] Compared with the prior art, the beneficial effects of this utility model are:
[0018] The spiral guide vanes use centrifugal force to initially separate sand and coal dust from the gas. After passing through the spiral guide vanes, the gas undergoes multi-stage filtration through a multi-layer filter structure. Through the synergistic design of the multi-layer filter structure and the spiral guide vanes, the coalbed methane in the drainage pipeline can be intercepted in multiple stages, achieving efficient separation and discharge of sand and coal dust. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0020] Figure 1 This is a structural diagram of the external structure of the filter cartridge in this utility model.
[0021] Figure 2 This is a structural diagram of the internal structure of the filter cartridge in this utility model.
[0022] Figure 3 This utility model Figure 2 Enlarged view of the structure at point A in the middle.
[0023] Figure 4 This is a structural diagram of the inside of the guide tube in this utility model.
[0024] Figure 5 This is a structural diagram of the valve seat in this utility model.
[0025] The components include: 1. Filter cartridge; 2. Inlet pipe connector; 3. Outlet pipe connector; 4. End cap; 5. First flange; 6. Second flange; 7. Fixing bolt; 8. Flushing pipe; 9. Multi-layer filter structure; 91. First conical filter screen; 92. Second conical filter screen; 93. Third conical filter screen; 94. Fourth conical filter screen.
[0026] 10. Flow guide tube; 11. Spiral flow guide vane; 12. Sealing ring; 13. Valve cavity; 14. Spherical plug; 15. Conical outlet; 16. Spring; 17. Valve seat. Detailed Implementation
[0027] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0028] according to Figure 1 , 2 As shown in Figures 3, 4, and 5, this embodiment proposes a sand control device for coalbed methane drainage pipelines, including a filter cylinder 1, an inlet pipe joint 2 on the outside of the filter cylinder 1, the inlet pipe joint 2 being connected to the filter cylinder 1, and further including:
[0029] End cap 4 is detachably connected to the upper end of filter cartridge 1. The upper end of end cap 4 is provided with outlet pipe connector 3, and outlet pipe connector 3 is fixedly connected to end cap 4.
[0030] The guide tube 10 is placed inside the filter cartridge 1. The guide tube 10 is fixedly connected to the lower end of the outlet pipe joint 3. The guide tube 10 is connected to the outlet pipe joint 3.
[0031] The spiral guide vane 11 is sleeved on the outside of the guide tube 10, and the guide tube 10 and the spiral guide vane 11 are fixedly connected.
[0032] The multi-layer filter structure 9 is fixedly connected to the lower end of the guide tube 10 for multi-stage filtration of gas.
[0033] The inlet pipe connector 2 connects to the coalbed methane inlet, and the outlet pipe connector 3 connects to the coalbed methane outlet. Under pressure, the gas enters the filter cartridge 1 and flows downward along the spiral guide vane 11. Under the guidance of the spiral guide vane 11, a swirling flow field is formed. The spiral guide vane 11 uses centrifugal force to throw denser sand particles and coal powder towards the pipe wall, so that the sand particles and coal powder are initially separated from the gas. After passing through the spiral guide vane 11, the gas will pass through the multi-layer filter structure 9 for multi-stage filtration. Through the synergistic design of the multi-layer filter structure 9 and the spiral guide vane 11, the coalbed methane in the discharge pipeline can be intercepted in multiple stages, realizing the efficient separation and discharge of sand particles and coal powder.
[0034] When cleaning the spiral guide vanes 11 and the multi-layer filter structure 9, simply loosen the fixing between the end cap 4 and the filter cartridge 1. Replacement and maintenance are convenient.
[0035] The flushing pipe 8 is located at the lower end of the filter cartridge 1, and a one-way valve is provided at the connection between the flushing pipe 8 and the filter cartridge 1.
[0036] Clean water is introduced into the bottom of the filter cartridge 1 through the flushing pipe 8 to backwash the multi-layer filter structure 9, which can prevent sand particles from embedding or clogging the multi-layer filter structure 9. The one-way valve is used to prevent gas from entering the flushing pipe 8.
[0037] Regarding the multi-layer filter structure 9:
[0038] The multi-layer filter structure 9 includes a first conical filter 91, a second conical filter 92, a third conical filter 93, and a fourth conical filter 94. The first conical filter 91 and the second conical filter 92 are both sleeved on the outside of the guide cylinder 10. The second conical filter 92 is placed below the first conical filter 91. The first conical filter 91 and the second conical filter 92 are both fixedly connected to the guide cylinder 10. The third conical filter 93 and the fourth conical filter 94 are placed inside the guide cylinder 10. The third conical filter 93 is placed below the fourth conical filter 94. The third conical filter 93 and the fourth conical filter 94 are both fixedly connected to the guide cylinder 10.
[0039] The gas flows downward along the spiral guide vane 11, first passing through the first conical filter 91, which filters the gas, then through the second conical filter 92, which filters the gas a second time. The filtered gas enters the guide tube 10 from the bottom, and is filtered again by the third conical filter 93 and the fourth conical filter 94. Finally, the gas is discharged from the outlet pipe joint 3 through the guide tube 10.
[0040] It is worth explaining in detail that the mesh size of the first conical filter 91, the second conical filter 92, the third conical filter 93, and the fourth conical filter 94 increases sequentially. The first conical filter 91 and the second conical filter 92 are primary filters, while the third conical filter 93 and the fourth conical filter 94 are secondary filters. The primary filters intercept large sand particles, while the secondary filters capture fine coal dust. This staged filtration reduces the load on individual filter stages.
[0041] It should be noted that there are gaps between the spiral guide vane 11, the first conical filter screen 91 and the second conical filter screen 92 and the inner wall of the filter cylinder 1. Centrifugal force throws denser sand and coal powder toward the inner wall of the filter cylinder 1, and they slide down the inner wall of the filter cylinder 1 to the bottom of the filter cylinder 1. Each stage of the filter screen adopts a conical design, and the sand particles also slide down the conical surface to the bottom of the filter cylinder 1 under the action of gravity, avoiding accumulation.
[0042] Regarding check valves:
[0043] The one-way valve includes a valve seat 17, which is fixedly connected to the lower end of the filter cartridge 1. A valve chamber 13 is formed at the lower end of the valve seat 17, and a conical outlet 15 is formed at the upper end of the valve seat 17. The conical outlet 15 communicates with the valve chamber 13, which in turn communicates with the flushing pipe 8. A spherical plug 14 is provided inside the conical outlet 15, engaging with it. A spring 16 is provided inside the valve chamber 13, with one end fixedly connected to the spherical plug 14 and the other end fixedly connected to the inner wall of the valve chamber 13. The flushing pipe 8 is connected to a pump, and clean water enters the valve chamber 13 through the flushing pipe 8. As the hydraulic pressure inside the valve chamber 13 increases, the spherical plug 14 rises, opening the conical outlet 15, allowing clean water to enter the filter cartridge 1 through the conical outlet 15. Regular backwashing of the multi-layer filter structure 9 prevents sand particles from embedding or clogging.
[0044] To facilitate the assembly and disassembly of the end cap 4, a first flange 5 is provided along the lower edge of the end cap 4, which is fixedly connected to the end cap 4. A second flange 6 is provided along the upper edge of the filter cylinder 1, which is fixedly connected to the filter cylinder 1. The first flange 5 is equipped with multiple sets of fixing bolts 7 for fixing the second flange 6. The end cap 4 and the filter cylinder 1 are fixed by a flange connection. When the end cap 4 is opened, the fixing bolts 7 on the first flange 5 are unscrewed from the bolt holes on the second flange 6.
[0045] To enhance the seal at the connection between the end cap 4 and the filter cartridge 1, sealing rings 12 are provided on the facing sides of the first flange 5 and the second flange 6, and the two sets of sealing rings 12 are fixedly connected to the first flange 5 and the second flange 6 respectively.
[0046] How this application works:
[0047] The inlet pipe connector 2 connects to the coalbed methane inlet, and the outlet pipe connector 3 connects to the coalbed methane outlet. Under pressure, the gas enters the filter cartridge 1 and flows downward along the spiral guide vane 11. Under the guidance of the spiral guide vane 11, a swirling flow field is formed. The spiral guide vane 11 uses centrifugal force to throw denser sand particles and coal powder towards the pipe wall, so that the sand particles and coal powder are initially separated from the gas. After passing through the spiral guide vane 11, the gas will pass through the multi-layer filter structure 9 for multi-stage filtration. Through the synergistic design of the multi-layer filter structure 9 and the spiral guide vane 11, the coalbed methane in the discharge pipeline can be intercepted in multiple stages, realizing the efficient separation and discharge of sand particles and coal powder.
[0048] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.
[0049] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.
Claims
1. A sand control device for coal bed gas drainage pipeline, comprising a filter cartridge (1), an inlet pipe joint (2) is arranged outside the filter cartridge (1), and the inlet pipe joint (2) communicates with the filter cartridge (1), characterized in that, Also include: End cover (4) can be detachably connected to the upper end of the filter cartridge (1), the upper end of the end cover (4) is provided with the exhaust pipe joint (3), the exhaust pipe joint (3) is fixedly connected with the end cover (4); Flow guide cylinder (10) is placed in the filter cartridge (1), the lower end of the flow guide cylinder (10) is fixedly connected with the exhaust pipe joint (3), the flow guide cylinder (10) is communicated with the exhaust pipe joint (3); Spiral flow guide vane (11) is sleeved on the outside of the flow guide cylinder (10), the flow guide cylinder (10) is fixedly connected with the spiral flow guide vane (11); Multi-layer filter screen structure (9) is fixedly connected with the lower end of the flow guide cylinder (10), which is used for multi-stage filtering of gas; The flushing pipe (8) is placed at the lower end of the filter cartridge (1), and the connection between the flushing pipe (8) and the filter cartridge (1) is provided with a one-way valve.
2. The sand control device for coalbed gas production tubing as claimed in claim 1, wherein: The multi-layer filter screen structure (9) comprises a first conical filter screen (91), a second conical filter screen (92), a third conical filter screen (93) and a fourth conical filter screen (94); The first conical filter screen (91) and the second conical filter screen (92) are both sleeved on the outside of the flow guide cylinder (10), the second conical filter screen (92) is placed below the first conical filter screen (91), and the first conical filter screen (91) and the second conical filter screen (92) are both fixedly connected with the flow guide cylinder (10); The third conical filter screen (93) and the fourth conical filter screen (94) are placed on the inside of the flow guide cylinder (10), the third conical filter screen (93) is placed below the fourth conical filter screen (94), and the third conical filter screen (93) and the fourth conical filter screen (94) are both fixedly connected with the flow guide cylinder (10).
3. The sand control device for coal seam gas production tubing as claimed in claim 2, wherein: The mesh number of the first conical filter screen (91), the second conical filter screen (92), the third conical filter screen (93) and the fourth conical filter screen (94) increases in turn.
4. The sand control device for coal seam gas production tubing of claim 2, wherein: The spiral flow guide vane (11), the first conical filter screen (91) and the second conical filter screen (92) are provided with a spacing between the inside wall of the filter cartridge (1).
5. The sand control device for coal seam gas production tubing of claim 1, wherein: The one-way valve comprises a valve seat (17), the valve seat (17) is fixedly connected with the lower end of the filter cartridge (1), the lower end of the valve seat (17) is provided with a valve cavity (13), the upper end of the valve seat (17) is provided with a conical exhaust port (15), the conical exhaust port (15) is communicated with the valve cavity (13), the valve cavity (13) is communicated with the flushing pipe (8), the conical exhaust port (15) is provided with a spherical plug (14), the spherical plug (14) is matched with the conical exhaust port (15), the valve cavity (13) is provided with a spring (16), one end of the spring (16) is fixedly connected with the spherical plug (14), and the other end of the spring (16) is fixedly connected with the inside wall of the valve cavity (13).
6. The sand control device for coal seam gas production tubing of claim 1, wherein: The lower end of the end cover (4) is provided with a first flange plate (5), the first flange plate (5) is fixedly connected with the end cover (4), the upper end of the filter cartridge (1) is provided with a second flange plate (6), the second flange plate (6) is fixedly connected with the filter cartridge (1), and a plurality of groups of fixing pins (7) for fixing the second flange plate (6) are assembled on the first flange plate (5).
7. The sand control device for coal seam gas production tubing of claim 6, wherein: The first flange plate (5) and the second flange plate (6) are provided with sealing rings (12) on the side of the view, and two groups of sealing rings (12) are fixedly connected with the first flange plate (5) and the second flange plate (6) respectively.