Efficient gas filtering device for underground coal gasification curve type production well
By designing spiral ribs and multi-layer filter media in the curved production well, combined with differential pressure monitoring and backwashing units, the problem of uneven impurity distribution in existing equipment has been solved, achieving efficient purification of coal gas and continuous operation of the equipment, thus improving the purification effect and the service life of the equipment.
Patent Information
- Application Number
- CN202512042451.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-31
- Publication Date
- 2026-02-24
AI Technical Summary
The existing production well filtration devices fail to effectively utilize the shape of the curved production well, resulting in uneven distribution of impurities, low filtration efficiency, and frequent maintenance, which affects the continuity of production.
A curved production well filtration device with spiral ribs is designed. It utilizes the centrifugal force generated by airflow deflection for pre-separation. Combined with multi-layer filter media and differential pressure monitoring, it achieves automatic backwashing to ensure purification effect and continuous operation of the device.
By using centrifugal pre-separation and multi-layer filter media, the purification efficiency is improved, the service life and lifespan of the fine filter unit are extended, the cleaning frequency is reduced, and the high-quality purification of the gas and the continuous operation of the equipment are ensured.
Smart Images
Figure CN121556838A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of underground coal gasification (UCG) gas purification technology, and in particular to a high-efficiency gas filtration device for an underground coal gasification curved production well. Background Technology
[0002] The coal gas produced by underground coal gasification contains coal dust, ash, tar droplets and acidic impurities, which need to be filtered and purified when it is exported through the production well.
[0003] Existing production well filtration devices have significant drawbacks: most are designed for vertical well structures and do not utilize the well shape to optimize filtration; the airflow in vertical wells flows in a straight line, making it easy for impurities to adhere evenly to the filter medium, leading to blockage; although curved production wells can generate centrifugal force by changing the airflow direction, existing devices are not adapted to this characteristic, and instead cause uneven distribution of impurities due to eddies, resulting in low filtration efficiency, frequent maintenance, and seriously affecting production continuity.
[0004] To address this, a high-efficiency gas filtration device for underground coal gasification bend-type production wells is proposed. Summary of the Invention
[0005] Therefore, the technical problem to be solved by the present invention is: how to improve the purification effect during operation by utilizing the shape of the curved production well.
[0006] The above-mentioned technical problems are solved by the following technical solution: This invention proposes a high-efficiency gas filtration device for underground coal gasification bend-type production wells, comprising, The conveying channel includes an inlet channel, a connecting channel, and an outlet channel connected in sequence. The first bend connects the entry channel and the connecting channel, and the first bend is provided with a plurality of spirally arranged first spiral ribs. The second bend is used to connect the connecting channel and the discharge channel. The second bend is provided with a plurality of spirally arranged second spiral ribs. The height of the first curve is greater than the height of the second curve.
[0007] In a preferred embodiment of the high-efficiency gas filtration device for underground coal gasification bend-type production wells of the present invention: a gathering channel is provided at the second bend, and a slag discharge port is provided on the gathering channel.
[0008] In a preferred embodiment of the high-efficiency gas filtration device for underground coal gasification bend-type production wells of the present invention, it further includes a fine filtration unit located at the discharge channel, the fine filtration unit filtering the medium passing through the discharge channel.
[0009] In a preferred embodiment of the high-efficiency gas filtration device for underground coal gasification bend-type production wells of the present invention, it further includes a differential pressure monitoring unit disposed on the discharge channel, the differential pressure monitoring unit being used to detect the differential pressure across the fine filtration unit.
[0010] In a preferred embodiment of the high-efficiency gas filtration device for underground coal gasification bend-type production wells of the present invention: it further includes a backwashing unit provided in the discharge channel, the backwashing unit being used to flush and clean the fine filtration unit; When the differential pressure value detected by the differential pressure monitoring unit exceeds the set threshold, the backwashing unit is activated to backwash and clean the fine filter unit.
[0011] In a preferred embodiment of the high-efficiency gas filtration device for underground coal gasification bend-type production wells of the present invention: the fine filtration unit includes a high-temperature resistant metal filter screen, a porous ceramic filter layer, and a modified activated carbon fiber layer stacked sequentially.
[0012] In a preferred embodiment of the high-efficiency gas filtration device for underground coal gasification bend-type production wells of the present invention: the differential pressure monitoring unit includes a differential pressure monitoring box disposed on the discharge channel, and the differential pressure monitoring box is provided with a first differential pressure sensor and a second differential pressure sensor; The first differential pressure sensor is located at the inlet end of the fine filtration unit; The second differential pressure sensor is located at the discharge end of the fine filtration unit.
[0013] In a preferred embodiment of the high-efficiency gas filtration device for underground coal gasification bend-type production wells of the present invention: the backwashing unit includes a gas transmission pipe, a uniformly distributed pipe disposed at the output end of the gas transmission pipe, and a jet hole disposed on the uniformly distributed pipe.
[0014] In a preferred embodiment of the high-efficiency gas filtration device for underground coal gasification bend-type production wells of the present invention: the fine filtration unit is provided with an upper sealing flange; The discharge channel is equipped with a lower sealing flange; The discharge channel and the fine filtration unit are connected by a lower sealing flange and an upper sealing flange.
[0015] In a preferred embodiment of the high-efficiency gas filtration device for underground coal gasification bend-type production wells of the present invention: a lower reinforcing support is provided on the inlet channel, and the lower reinforcing support is connected to the second bend; The discharge channel is equipped with an upper reinforcing bracket, which is connected to the first bend.
[0016] The beneficial effects of this invention are as follows: This invention can utilize the characteristics of the curved flow field to improve the separation efficiency. By using the centrifugal force generated by the airflow turning, larger impurities can be pre-separated, which can improve the service life and lifespan of the fine filter unit, reduce the number of cleanings, and extend the clogging cycle. Through three layers of filter media with different pore sizes, coal dust, ash, tar, and acidic impurities are intercepted and adsorbed step by step, ensuring the quality of coal gas purification. By monitoring the pressure difference to trigger the backwashing unit, the fine filter unit can be automatically cleaned without interrupting production, reducing the frequency of manual intervention and improving the continuity of equipment operation. Attached Figure Description
[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention.
[0018] Figure 1 A schematic diagram of the connection structure of the conveying channel, the first bend, and the second bend of the high-efficiency gas filtration device in the underground coal gasification bend-type production well is shown.
[0019] Figure 2 A schematic diagram of the fine filtration unit of a high-efficiency gas filtration device for underground coal gasification bend-type production wells is shown.
[0020] Figure 3 A schematic diagram of the overall structure of a high-efficiency gas filtration device for an underground coal gasification bend-type production well is shown.
[0021] Figure 4 A schematic diagram of the structure of a high-efficiency gas filtration device in the decomposed state of an underground coal gasification bend-type production well is shown.
[0022] In the diagram: 1. Conveying channel; 11. Inlet channel; 111. Lower reinforcing support; 12. Connecting channel; 13. Discharge channel; 131. Upper reinforcing support; 132. Lower sealing flange; 2. First bend; 21. First spiral rib; 3. Second bend; 31. Second spiral rib; 32. Gathering channel; 33. Slag discharge port; 4. Fine filtration unit; 41. High-temperature resistant metal filter screen; 42. Porous ceramic filter layer; 43. Modified activated carbon fiber layer; 44. Upper sealing flange; 5. Differential pressure monitoring unit; 51. Differential pressure monitoring box; 52. First differential pressure sensor; 53. Second differential pressure sensor; 6. Backwashing unit; 61. Gas delivery pipe; 62. Distribution pipe; 63. Injection hole. Detailed Implementation
[0023] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.
[0024] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.
[0025] Reference Figure 1 This embodiment provides a high-efficiency gas filtration device for underground coal gasification bend-type production wells, including, The conveying channel 1 includes an inlet channel 11, a connecting channel 12, and an outlet channel 13 connected in sequence. The inlet channel 11, the connecting channel 12, and the outlet channel 13 are arranged in a Z-shape. The gas first enters the inlet channel 11, passes through the connecting channel 12, and is finally discharged from the outlet channel 13.
[0026] The first bend 2 is used to connect the entry channel 11 and the connecting channel 12. The first bend 2 is provided with a number of first spiral ribs 21 arranged in a spiral shape. The first spiral ribs 21 themselves are spirally arranged, and the other number of first spiral ribs 21 are evenly distributed in a spiral shape on the inner wall of the first bend 2.
[0027] The second bend 3 is used to connect the connecting channel 12 and the discharge channel 13. The second bend 3 is provided with a number of second spiral ribs 31 arranged in a spiral shape. The second spiral ribs 31 themselves are spirally arranged, and the other number of second spiral ribs 31 are evenly distributed in a spiral shape on the inner wall of the second bend 3.
[0028] The height of the first curve 2 is greater than the height of the second curve 3.
[0029] Preferably, a collection channel 32 is provided at the second bend 3, and a slag discharge port 33 is provided on the collection channel 32.
[0030] During operation, when the gas passes through the first bend 2, larger impurities are difficult to turn quickly due to the greater centrifugal force, and therefore easily come into contact with the inner wall of the first bend 2. Guided by the spiral first helical rib 21, they easily move along the trajectory of the first helical rib 21, so the gas can pass smoothly through the center of the conveying channel 1, while the impurities tend to move towards the periphery of the pipe. For larger coal dust and large ash particles, they will slide along the surface of the connecting channel 12 after entering it. Similarly, the impurities will come into contact with the inner wall of the second bend 3 again due to the centrifugal force. After being guided by the second helical rib 31, they finally fall into the gathering channel 32. The gathering channel 32 can remove the centrifugally dispersed impurities at the second bend 3, achieving preliminary treatment of the gas. The first bend 2 and the first helical rib 21 can assist the impurities to move to the periphery of the pipe to improve the separation effect at the second bend 3. The slag discharge port 33 can clean the impurities located in the gathering channel 32.
[0031] The inlet channel 11 is provided with a lower reinforcing bracket 111, which is connected to the second bend 3; the outlet channel 13 is provided with an upper reinforcing bracket 131, which is connected to the first bend 2. The lower reinforcing bracket 111 and the upper reinforcing bracket 131 can increase the structural strength of the inlet channel 11, the connecting channel 12, and the outlet channel 13.
[0032] Preferably, the angle between the inlet channel 11 and the connecting channel 12, and between the connecting channel 12 and the outlet channel 13, is set at 45 degrees. This ensures the centrifugal force when the airflow turns, while also preventing the airflow from hitting the pipe wall and forming a backflow vortex due to excessively large bends.
[0033] It should be noted that an automatic slag discharge valve can be installed at slag discharge port 33 to automatically clean up accumulated dust and particles, preventing the accumulation of impurities.
[0034] In summary, this invention is specifically designed for curved production wells and can utilize the characteristics of curved flow fields to improve filtration efficiency, removing larger impurity particles through centrifugal force.
[0035] Reference Figures 1-4 As an optional embodiment, it also includes a fine filtration unit 4 located at the discharge channel 13, which filters the medium passing through the discharge channel 13.
[0036] Specifically, the fine filtration unit 4 includes a high-temperature resistant metal filter screen 41, a porous ceramic filter layer 42, and a modified activated carbon fiber layer 43 stacked in sequence.
[0037] By sequentially stacking the high-temperature resistant metal filter 41, the porous ceramic filter layer 42, and the modified activated carbon fiber layer 43, the filtration effect of the fine filtration unit 4 on the media can be initially improved.
[0038] It should be noted that the filtration pore size of the high-temperature resistant metal filter 41 is 15μm, the filtration pore size of the porous ceramic filter layer 42 is 3μm, and the filtration pore size of the modified activated carbon fiber layer 43 is 0.8μm.
[0039] Step-by-step filtration can trap fine particles and tar layer by layer, improving the quality of coal gas production.
[0040] The design of the first bend 2 and the second bend 3 can reduce the impurities entering the fine filter unit 4 and extend the service life of the fine filter unit 4.
[0041] Preferably, it also includes a differential pressure monitoring unit 5 disposed on the discharge channel 13, the differential pressure monitoring unit 5 being used to detect the differential pressure across the fine filtration unit 4.
[0042] When the detected pressure difference between the two ends is small, it indicates that the filtration performance of the fine filter unit 4 is good. When the pressure difference between the two ends is large, it indicates that the fine filter unit 4 is severely clogged and the filtration effect is poor, requiring timely cleaning. Therefore, a pressure difference threshold between the two ends of the fine filter unit 4 can be set according to the production needs. When the detected pressure difference exceeds the set threshold, the staff will be prompted to clean the fine filter unit 4.
[0043] Preferably, it also includes a backwashing unit 6 located in the discharge channel 13. The backwashing unit 6 is used to flush and clean the fine filter unit 4. When the differential pressure value detected by the differential pressure monitoring unit 5 exceeds the set threshold, the backwashing unit 6 is activated to backwash and clean the fine filter unit 4.
[0044] By cleaning the fine filter unit 4 in a timely manner, the filtration performance of the fine filter unit 4 can be guaranteed, and the production capacity can be improved.
[0045] The differential pressure monitoring unit 5 includes a differential pressure monitoring box 51 located on the discharge channel 13. The differential pressure monitoring box 51 is equipped with a first differential pressure sensor 52 and a second differential pressure sensor 53. Specifically, the first differential pressure sensor 52 is located at the inlet end of the fine filtration unit 4, and the second differential pressure sensor 53 is located at the outlet end of the fine filtration unit 4.
[0046] The pressure at the second bend 3 is detected by the first differential pressure sensor 52, and the pressure at the discharge end of the discharge channel 13 is detected by the second differential pressure sensor 53. The differential pressure monitoring box 51 calculates the pressure difference between the two ends of the fine filter unit 4 to determine the blockage of the fine filter unit 4.
[0047] It should be noted that the backwashing unit 6 includes an air supply pipe 61 and a uniform distribution pipe 62 located at the output end of the air supply pipe 61, as well as injection holes 63 located on the uniform distribution pipe 62. The air supply pipe 61 is connected to an external high-pressure air source, which can supply high-pressure gas into the air supply pipe 61. The uniform distribution pipe 62 has a ring structure, and the injection holes 63 are evenly distributed on the uniform distribution pipe 62. The high-pressure gas is transported to the uniform distribution pipe 62 through the air supply pipe 61 and finally sprayed out from each injection hole 63 to perform a flushing operation on the fine filter unit 4. When cleaning the fine filter unit 4, the front end of the inlet channel 11 can be closed by controlling the valve and the slag discharge port 33 can be opened. At this time, the high-pressure gas can blow out the particles blocked in the fine filter unit 4, and at the same time clean the slag discharge port 33 and the collection channel 32, so that impurities, dust and particulate matter are discharged, and a rapid cleaning operation of the fine filter unit 4 can be achieved.
[0048] Furthermore, the fine filtration unit 4 is provided with an upper sealing flange 44; the discharge channel 13 is provided with a lower sealing flange 132; the discharge channel 13 and the fine filtration unit 4 are connected by the lower sealing flange 132 and the upper sealing flange 44.
[0049] The upper sealing flange 44 and the lower sealing flange 132 can be used to seal the fine filter unit 4 and the discharge channel 13. The upper sealing flange 44 and the lower sealing flange 132 can be installed and removed by bolts, which facilitates the disassembly and cleaning of the fine filter unit 4 and makes it convenient for replacement and maintenance.
[0050] In summary, this invention can utilize the characteristics of curved flow fields to improve separation efficiency. By using the centrifugal force generated by airflow deflection to pre-separate larger impurities, it can extend the service life and lifespan of the fine filter unit, reduce cleaning frequency, and prolong the clogging cycle. Through three layers of filter media with different pore sizes, it achieves step-by-step interception and adsorption of coal dust, ash, tar, and acidic impurities, ensuring the quality of coal gas purification. By monitoring the pressure difference to trigger the backwashing unit, it can automatically clean the fine filter unit 4 without interrupting production, reducing the frequency of manual intervention and improving the continuity of equipment operation.
[0051] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.
Claims
1. A high-efficiency gas filtration device for an underground coal gasification bend-type production well, characterized in that: include, The conveying channel (1) includes an inlet channel (11), a connecting channel (12), and an outlet channel (13) connected in sequence. The first bend (2) is used to connect the entry channel (11) and the connecting channel (12). The first bend (2) is provided with a plurality of first spiral ribs (21) arranged in a spiral. The second bend (3) is used to connect the connecting channel (12) and the discharge channel (13). The second bend (3) is provided with a plurality of spirally arranged second spiral ribs (31). The height of the first curve (2) is greater than the height of the second curve (3).
2. The high-efficiency gas filtration device for underground coal gasification curved production wells according to claim 1, characterized in that: A collection channel (32) is provided at the second bend (3), and a slag discharge port (33) is provided on the collection channel (32).
3. The high-efficiency gas filtration device for underground coal gasification curved production wells according to claim 2, characterized in that: It also includes a fine filtration unit (4) located at the discharge channel (13), which filters the medium passing through the discharge channel (13).
4. The high-efficiency gas filtration device for underground coal gasification curved production wells according to claim 3, characterized in that: It also includes a differential pressure monitoring unit (5) installed on the discharge channel (13), which is used to detect the differential pressure at both ends of the fine filtration unit (4).
5. The high-efficiency gas filtration device for underground coal gasification curved production wells according to claim 4, characterized in that: It also includes a backwashing unit (6) located in the discharge channel (13), the backwashing unit (6) being used to flush and clean the fine filter unit (4); When the differential pressure value detected by the differential pressure monitoring unit (5) exceeds the set threshold, the backwashing unit (6) is activated to backwash and clean the fine filter unit (4).
6. The high-efficiency gas filtration device for underground coal gasification curved production wells according to claim 3, characterized in that: The fine filtration unit (4) includes a high-temperature resistant metal filter screen (41), a porous ceramic filter layer (42), and a modified activated carbon fiber layer (43) stacked in sequence.
7. The high-efficiency gas filtration device for underground coal gasification curved production wells according to claim 4, characterized in that: The differential pressure monitoring unit (5) includes a differential pressure monitoring box (51) disposed on the discharge channel (13), and the differential pressure monitoring box (51) is provided with a first differential pressure sensor (52) and a second differential pressure sensor (53). The first differential pressure sensor (52) is located at the inlet end of the fine filtration unit (4); The second differential pressure sensor (53) is located at the discharge end of the fine filtration unit (4).
8. The high-efficiency gas filtration device for underground coal gasification curved production wells according to claim 5, characterized in that: The backwashing unit (6) includes an air supply pipe (61) and a uniform distribution pipe (62) located at the output end of the air supply pipe (61), and also includes a spray hole (63) located on the uniform distribution pipe (62).
9. The high-efficiency gas filtration device for underground coal gasification bend-type production wells according to any one of claims 3 to 8, characterized in that: The fine filtration unit (4) is provided with an upper sealing flange (44). The discharge channel (13) is provided with a lower sealing flange (132); The discharge channel (13) and the fine filter unit (4) are connected by a lower sealing flange (132) and an upper sealing flange (44).
10. The high-efficiency gas filtration device for underground coal gasification curved production wells according to claim 1, characterized in that: The entry channel (11) is provided with a lower reinforcing bracket (111), which is connected to the second bend (3); The discharge channel (13) is provided with an upper reinforcing bracket (131), which is connected to the first bend (2).