Geological carbon dioxide sequestration injection well structure and well completion process

Abstract

The invention discloses a carbon dioxide geological sequestration injection well structure and a well completion technology, and relates to the technical field of carbon dioxide sequestration and environmental protection. The outer injection tube is arranged on the peripheral side of the inner injection tube in a sleeving mode through a buffering assembly, and a cavity is formed between the inner injection tube and the outer injection tube; the supporting assembly is arranged in the injection inner tube and used for supporting the injection inner tube; wherein the injection outer tube slides on the outer side of the injection inner tube; the device has the effect of reducing damage to the injection pipeline.

Description

Technical Field

[0001] The present application relates to the field of carbon dioxide storage and environmental protection technology, and in particular to a carbon dioxide geological storage injection well structure and a well construction process. Background Art

[0002] Carbon dioxide geological storage is a technology that injects carbon dioxide into underground geological structures, using geological layers as natural storage reservoirs for long-term storage, thereby isolating carbon dioxide from the atmosphere and reducing its impact on climate change.

[0003] The existing carbon dioxide geological storage technology condenses carbon dioxide into liquid and then injects it into the storage layer through an injection pipe. The injection pipe is often made of a combination of multi-layer metal pipes and cement pipes.

[0004] When carbon dioxide is injected into the storage layer through an injection pipe, since the injection pipe is often made of a combination of multiple layers of metal pipes and cement pipes, when carbon dioxide is not transmitted inside the pipe, it needs to withstand the huge pressure inside the ground, and the injection pipe is easily damaged. Summary of the invention

[0005] In order to reduce the problem of injection pipe damage, the present application provides a carbon dioxide geological storage injection well structure and a well completion process.

[0006] The present application provides a carbon dioxide geological storage injection well structure, which adopts the following technical solution: A carbon dioxide geological storage injection well structure, comprising: An injection outer tube, wherein the injection outer tube is sleeved on the outer circumference of the injection inner tube through a buffer assembly, and a cavity is formed between the injection inner tube and the injection outer tube; A support assembly, the support assembly is disposed in the injection inner tube and is used to support the injection inner tube; Wherein, the injection outer tube slides on the outer side of the injection inner tube.

[0007] By adopting the above technical solution, the injection inner tube and the injection outer tube are injected into the soil layer at the same time, and then the carbon dioxide is injected into the geological layer. When carbon dioxide is not transmitted, the geological layer squeezes the injection outer tube under the action of a long time, and then the injection outer tube moves toward the direction of the injection inner tube, and the buffer component moves, thereby driving the support component to contact the inner wall of the injection inner tube, thereby reducing the huge pressure inside the ground when carbon dioxide is not transmitted inside the pipeline, causing damage to the injection inner tube and the injection outer tube.

[0008] Optionally, the buffer component includes: A first screw, the first screw being rotatably disposed at one end of the cavity close to the outer circumference of the injection inner tube; A buffer block, wherein two buffer blocks are provided, and both of the two buffer blocks are sleeved on the first screw rod; A spring, one end of which is fixedly arranged at one end of the cavity close to the inner circumference of the injection outer tube; A first moving block, one end of which is fixedly connected to an end of the spring away from the inner circumference of the injection outer tube; A first connecting rod, one end of which is hinged to the buffer block, and the other end of which is hinged to the first moving block; Wherein, the spring drives the first moving block to move.

[0009] By adopting the above technical solution, when the geological layer is squeezed toward the injection outer tube, the injection outer tube moves toward the direction close to the injection inner tube, and at the same time, the spring and the first moving block both move toward the injection inner tube. Since the first connecting rod is hinged to the first moving block and the buffer block, when the first moving block moves, it drives the first connecting rod to push the buffer block to move in the opposite direction on the first screw, so that the injection outer tube has a buffer space when it is squeezed externally.

[0010] Optionally, the support assembly is connected to the buffer assembly via a transmission member, and the support assembly includes: a second screw, the second screw being rotatably disposed in the cavity; A limit block, wherein the limit block is sleeved on the second screw rod; Support rods, wherein two support rods are provided, one end of each of the two support rods is hinged to the two ends of the limit block, and the other end of each support rod is in contact with the inner circumference of the injection inner tube; A second connecting rod, wherein two second connecting rods are provided, and one end of each of the two second connecting rods is slidably connected to one end of the support rod; The second moving block is slidably connected to the second screw rod, and the second moving block is fixedly connected to an end of the second connecting rod away from the supporting rod.

[0011] By adopting the above technical solution, when the second screw rotates, the second moving block slides in the direction of the limit block, and the second moving block drives the second connecting rod to slide in the direction of the limit block in the slide slot. Since the support rod is hinged with the limit block, the second connecting rod will drive the guide block to slide in the direction of the limit block in the slide slot during the movement in the direction of the limit block, and then the limit block drives the support rod to open, so that the free end of the support rod contacts the inner circumference of the injection inner tube, increasing the support effect of the injection inner tube, thereby reducing the huge pressure inside the ground when there is no carbon dioxide transmission inside the pipeline, which causes damage to the injection inner tube.

[0012] Optionally, the transmission member includes: A first bevel gear, one end of which is fixedly mounted on the upper end of the first screw rod; A transmission rod, one end of which is fixedly connected to the other end of the first bevel gear; A second bevel gear, one end of the second bevel gear is fixedly connected to the second screw rod, and the other end of the second bevel gear is fixedly connected to an end of the transmission rod away from the first bevel gear.

[0013] By adopting the above technical solution, when the first screw rotates, it drives the first bevel gear to rotate, and the first bevel gear drives the transmission rod and the second bevel gear to rotate, so that the second bevel gear drives the second screw to rotate, and then when the injection outer tube is squeezed by the geological layer, the support rod is driven to contact the inner wall of the injection inner tube, which is convenient and quick.

[0014] Optionally, the injection outer tube and the injection inner tube both include a first cement layer, a second steel tube layer is fixedly sleeved inside the first cement layer, a second steel tube layer is fixedly sleeved inside the second cement layer, and the first steel tube layer is fixedly sleeved inside the second cement layer.

[0015] By adopting the above technical solution, both the injection inner tube and the injection outer tube are provided with a first cement layer, a second steel tube layer, a second cement layer and a first steel tube layer, which can enhance the mechanical strength of the injection outer tube and the injection inner tube.

[0016] Optionally, multiple groups of support components are provided.

[0017] By adopting the above technical solution, a plurality of support components are provided, thereby increasing the supporting effect on the injection inner tube and extending the life of a single support component.

[0018] Optionally, the support rod is provided with a slide groove along the length direction of the support rod, and a guide block is fixedly provided at one end of the second connecting rod close to the slide groove, and the guide block is slidably arranged in the slide groove.

[0019] By adopting the above technical solution and setting the slide groove and the guide block, the second connecting rod will not separate from the support rod when the second connecting rod moves toward the limit block, thereby increasing the connection stability between the second connecting rod and the support rod.

[0020] Optionally, a carbon dioxide geological storage well formation process comprises: S1. Determine the diameters of the inner injection tube and the outer injection tube; S2, perfusing the inner injection tube and the outer injection tube; S3, determining the positions of the buffer assembly, the transmission member and the support assembly, and sealing the injection inner tube and the injection outer tube; S4. Injecting the injection well into a geological storage structure and penetrating into a storage layer, wherein the geological storage structure includes a storage layer, a cap rock is fixedly disposed on the upper end of the storage layer, and a soil layer is fixedly disposed on the upper end of the cap rock.

[0021] By adopting the above technical scheme, when the injection well is penetrated into the storage layer, it is necessary to determine the diameters of the injection inner tube and the injection outer tube so that the injection well can be injected into the geological storage structure. The injection outer tube and the injection inner tube are perfused according to the strength requirements of the injection outer tube and the injection inner tube, thereby increasing the mechanical strength of the injection inner tube and the injection outer tube. The buffer assembly, transmission parts and support assembly are fixed in the injection inner tube and the injection outer tube, and then the injection outer tube is sealed. Finally, the injection well is injected into the geological storage structure and penetrated into the storage layer, thereby increasing the convenience of carbon dioxide storage.

[0022] In summary, the embodiments of the present invention provide a carbon dioxide geological storage injection well structure and well completion process, which include at least one of the following beneficial technical effects: 1. When the geological layer is squeezed toward the injection outer tube, the injection outer tube moves toward the injection inner tube, and at the same time, the spring and the first moving block both move toward the injection inner tube. Since the first connecting rod is hinged to the first moving block and the buffer block, when the first moving block moves, it drives the first connecting rod to push the buffer block to move in the opposite direction on the first screw, so that the injection outer tube has a buffer space when it is squeezed externally.

[0023] 2. When the second screw rotates, the second moving block slides in the direction of the limit block, and the second moving block drives the second connecting rod to slide in the direction of the limit block in the slide slot. Since the support rod is hinged with the limit block, the second connecting rod will drive the guide block to slide in the direction of the limit block in the slide slot during its movement in the direction of the limit block, and then the limit block drives the supporting rod to open, so that the free end of the supporting rod contacts the inner circumference of the injection inner tube, increasing the supporting effect of the injection inner tube, thereby reducing the huge pressure inside the ground when there is no carbon dioxide transmission inside the pipeline, which causes damage to the injection inner tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A cross-sectional view of a carbon dioxide geological storage injection well structure provided in Example 2 of the present invention; Figure 2 A schematic diagram of the structure of an injection inner tube and an injection outer tube in a carbon dioxide geological storage injection well structure provided in Embodiment 2 of the present invention; Figure 3 for Figure 1 A magnified view of part A; Figure 4 A schematic diagram of the structure of a support assembly in a carbon dioxide geological storage injection well structure provided in Example 2 of the present invention.

[0025] Description of the symbols in the figure: 11. Injection inner tube; 12. Injection outer tube; 13. Cavity; 2. Buffer assembly; 21. First screw; 22. Buffer block; 23. Spring; 24. First moving block; 25. First connecting rod; 3. Support assembly; 31. Second screw; 32. Limit block; 33. Support rod; 34. Second connecting rod; 35. Second moving block; 4. Transmission member; 41. First bevel gear; 42. Transmission rod; 43. Second bevel gear; 51. First cement layer; 52. Second steel pipe layer; 53. Second cement layer; 54. First steel pipe layer; 61. Guide block; 62. Slide; 7. Geological sealing structure; 71. Storage layer; 72. Cover rock; 73. Soil layer. DETAILED DESCRIPTION

[0026] The following is combined with Figure 1-4 This application is described in further detail.

[0027] Combination Figure 1 A carbon dioxide geological storage injection well includes an injection inner tube 11, an injection outer tube 12, a support assembly 3, and a buffer assembly 2. The injection inner tube 11 is used to inject carbon dioxide; the injection outer tube 12 is sleeved on the outer peripheral side of the injection inner tube 11 through the buffer assembly 2, and a cavity 13 is formed between the injection inner tube 11 and the injection outer tube 12; the support assembly 3 is arranged in the injection inner tube 11, and is used to support the injection inner tube 11; wherein the injection outer tube 12 slides on the outer side of the injection inner tube 11.

[0028] Combination Figure 2 In the embodiment of the present application, the injection inner tube 11 and the injection outer tube 12 are both arranged in an annular shape. It should be noted that the diameter of the injection outer tube 12 is larger than the diameter of the injection inner tube 11. The upper and lower ends of the injection outer tube 12 are provided with telescopic cavities, so that the injection outer tube 12 can move in a direction perpendicular to the axial direction of the injection outer tube 12 when squeezed. Among them, the injection inner tube 11 and the injection outer tube 12 both include a first cement layer 51, a second steel tube layer 52 is fixedly sleeved inside the first cement layer 51, a second cement layer 53 is fixedly sleeved inside the second steel tube layer 52, and a first steel tube layer 54 is fixedly sleeved inside the second cement layer 53, so as to increase the mechanical strength of the injection inner tube 11 and the injection outer tube 12.

[0029] During specific use, the injection inner tube 11 and the injection outer tube 12 are injected into the soil layer at the same time, and then the carbon dioxide is injected into the geological layer. When carbon dioxide is not transmitted, the geological layer squeezes the injection outer tube 12 under the action of a long time, and then the injection outer tube 12 moves toward the direction of the injection inner tube 11, and the buffer component 2 moves, thereby driving the support component 3 to contact the inner wall of the injection inner tube 11, thereby reducing the huge pressure inside the ground when carbon dioxide is not transmitted inside the pipeline, causing damage to the injection inner tube 11 and the injection outer tube 12.

[0030] Combination Figure 3 In a specific embodiment, the buffer assembly 2 includes: a first screw 21, a buffer block 22, a spring 23, a first moving block 24, and a first connecting rod 25. The first screw 21 is rotatably arranged at one end of the cavity 13 close to the outer circumference of the injection inner tube 11; two buffer blocks 22 are arranged, and the two buffer blocks 22 are both sleeved on the first screw 21; one end of the spring 23 is fixedly arranged at one end of the cavity 13 close to the inner circumference of the injection outer tube 12; one end of the first moving block 24 is fixedly connected to one end of the spring 23 away from the inner circumference of the injection outer tube 12; one end of the first connecting rod 25 is hinged to the buffer block 22, and the other end is hinged to the first moving block 24; wherein, the spring 23 drives the first moving block 24 to move.

[0031] In the embodiment of the present application, the first screw 21 is provided with a thread, and it should be noted that the length of the thread can be consistent with the length of the first screw 21 or can be sufficient to allow the buffer block 22 to move, and the embodiment of the present application does not make any specific limitations; the buffer block 22 can be hinged with the first connecting rod 25 and the first movable block 24 through a rotating shaft or through a hinge, and the specific hinge method is determined according to the specific usage; the circumferential side of the buffer block 22 in contact with the first screw 21 is provided with a thread, and the length of the first screw 21 is greater than the length of the injection inner tube 11.

[0032] During specific use, when the geological layer is squeezed toward the injection outer tube 12, the injection outer tube 12 moves toward the injection inner tube 11, and at the same time, the spring 23 and the moving block both move toward the injection inner tube 11. Since the first connecting rod 25 is hinged to the first moving block 24 and the buffer block 22, when the moving block moves, it drives the first connecting rod 25 to push the buffer block 22 to move in the opposite direction on the first screw 21, so that the injection outer tube 12 has a buffer space when it is squeezed from the outside.

[0033] Combination Figure 4In a specific embodiment, the support assembly 3 is connected to the buffer assembly 2 through a transmission member 4, and the support assembly 3 includes: a second screw 31, a limit block 32, a support rod 33, a second connecting rod 34, and a second moving block 35. The second screw 31 is rotatably arranged in the cavity 13; the limit block 32 is sleeved on the second screw 31; there are two support rods 33, one end of the two support rods 33 is hinged to the two ends of the limit block 32, and the other end is in contact with the inner circumference of the injection inner tube 11; there are two second connecting rods 34, one end of the two second connecting rods 34 is slidably connected to one end of the support rod 33; the second moving block 35 is slidably connected to the second screw 31, and the second moving block 35 is fixedly connected to one end of the second connecting rod 34 away from the support rod 33.

[0034] Among them, the transmission member 4 includes: a first bevel gear 41, a transmission rod 42, and a second bevel gear 43. One end of the first bevel gear 41 is fixedly arranged on the upper end of the first screw rod 21; one end of the transmission rod 42 is fixedly connected to the other end of the first bevel gear 41; one end of the second bevel gear 43 is fixedly connected to the second screw rod 31, and the other end is fixedly connected to one end of the transmission rod 42 away from the first bevel gear 41.

[0035] Specifically, a plurality of support components 3 are arranged at intervals along the axial direction of the injection inner tube 11 , thereby increasing the supporting effect on the injection inner tube 11 and extending the life of a single support component 3 .

[0036] In the embodiment of the present application, the shape of the stop block 32 and the second moving block 35 can be annular or square, which is not specifically limited in the embodiment of the present application. The second screw rod 31 is provided with a thread at the position of the second moving block 35, and the length of the thread is sufficient for the second moving block 35 to slide. The second connecting rod 34 and the support rod 33 can be circular or square, which are set according to specific use requirements. The guide block 61 is semi-arc-shaped, and the guide block 61 and the second connecting rod 34 are integrally formed. The support rod 33 is provided with a U-shaped groove on the side close to the second screw rod 31, and the side of the guide block 61 with an arc surface is placed in the U-shaped groove, and the peripheral side of the second moving block 35 in contact with the second screw rod 31 is provided with a thread. The first bevel gear 41 is fixedly connected to the upper end of the first screw rod 21 by welding or bonding, and the second bevel gear 43 is fixed to the upper end of the second screw rod 31 by bonding or welding, wherein the height of the second bevel gear 43 and the first bevel gear 41 can be consistent or inconsistent, as long as it does not affect the rotation of the first bevel gear 41 and the second bevel gear 43.

[0037] In specific use, when the first screw 21 rotates, it drives the first bevel gear 41 to rotate, and the first bevel gear 41 drives the transmission rod 42 and the second bevel gear 43 to rotate, so that the second bevel gear 43 drives the second screw 31 to rotate. During the rotation of the second screw 31, the second moving block 35 slides in the direction of the limit block 32, and the second moving block 35 drives the second connecting rod 34 to slide in the direction of the limit block 32 in the slide groove 62. Since the support rod 33 is hinged with the limit block 32, the second connecting rod 34 will drive the guide block 61 to slide in the direction of the limit block 32 in the slide groove 62 during the movement of the second connecting rod 34 in the direction of the limit block 32, and then the limit block 32 drives the support rod 33 to open, so that the free end of the support rod 33 contacts the inner circumference of the injection inner tube 11, thereby increasing the support effect of the injection inner tube 11, and thereby reducing the huge pressure inside the ground when there is no carbon dioxide transmission inside the pipeline, which causes the injection inner tube 11 to be damaged.

[0038] A carbon dioxide geological storage well construction process includes the following construction steps: S1, determining the diameters of the injection inner tube 11 and the injection outer tube 12; According to the evaluation index of carbon dioxide geological storage in deep coal seams and underground saline aquifers, the target area suitable for carbon dioxide storage is screened out, the most suitable storage site is selected, and then the diameters of the injection inner tube 11 and the injection outer tube 12 are determined.

[0039] S2, perfusing the inner injection tube 11 and the outer injection tube 12; S3, determining the positions of the buffer assembly 2, the transmission member 4 and the support assembly 3, and sealing the injection inner tube 11 and the injection outer tube 12; S4. The injection well structure is penetrated to the storage layer 71 , wherein the geological storage structure 7 comprises the storage layer 71 , a cap rock 72 is fixedly disposed on the upper end of the storage layer 71 , and a soil layer 73 is fixedly disposed on the upper end of the cap rock 72 .

[0040] The implementation principle of the embodiment of the present application is: the injection inner tube 11 and the injection outer tube 12 are injected into the soil layer at the same time, and then the carbon dioxide is injected into the geological layer. When the carbon dioxide is not transmitted, the geological layer squeezes the injection outer tube 12 under the action of a long time, and then the injection outer tube 12 moves in the direction of the injection inner tube 11, and the injection outer tube 12 moves in the direction close to the injection inner tube 11. At the same time, the spring 23 and the moving block both move in the direction of the injection inner tube 11. When the moving block moves, it drives the first connecting rod 25 to push the buffer block 22 to move in the opposite direction on the first screw 21. When the first screw 21 rotates, it drives the first bevel gear 41 to rotate, and the first bevel gear 41 drives the transmission rod 42 and the second bevel gear 43 to rotate. , so that the second bevel gear 43 drives the second screw 31 to rotate. During the rotation of the second screw 31, the second moving block 35 slides in the direction of the limit block 32, and the second moving block 35 drives the second connecting rod 34 to slide in the slide groove 62 in the direction of the limit block 32. In the process of moving in the direction of the limit block 32, the second connecting rod 34 will drive the guide block 61 to slide in the slide groove 62 in the direction of the limit block 32, and then the limit block 32 drives the support rod 33 to open, so that the free end of the support rod 33 contacts the inner circumference of the injection inner tube 11, thereby increasing the supporting effect of the injection inner tube 11, and thereby reducing the huge pressure inside the ground when no carbon dioxide is transmitted inside the pipeline, causing damage to the injection inner tube 11.

[0041] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A carbon dioxide geological storage injection well structure, characterized in that: include: An injection inner tube (11), wherein the injection inner tube (11) is used for injecting carbon dioxide; An injection outer tube (12), the injection outer tube (12) being sleeved on the outer circumference of the injection inner tube (11) via a buffer assembly (2), and a cavity (13) being formed between the injection inner tube (11) and the injection outer tube (12); A support component (3), the support component (3) being arranged in the injection inner tube (11) and being used to support the injection inner tube (11); Wherein, the injection outer tube (12) slides toward the outside of the injection inner tube (11); The buffer component (2) comprises: A first screw (21), the first screw (21) being rotatably disposed at one end of the cavity (13) close to the outer circumference of the injection inner tube (11); A buffer block (22), wherein two buffer blocks (22) are provided, and the two buffer blocks (22) are both sleeved on the first screw rod (21); a spring (23), one end of the spring (23) being fixedly mounted on one end of the cavity (13) close to the inner circumference of the injection outer tube (12); A first moving block (24), one end of the first moving block (24) being fixedly connected to an end of the spring (23) away from the inner circumference of the injection outer tube (12); a first connecting rod (25), one end of the first connecting rod (25) being hinged to the buffer block (22) and the other end of the first connecting rod (25) being hinged to the first moving block (24); The spring (23) drives the first moving block (24) to move.

2. A carbon dioxide geological storage injection well structure according to claim 1, characterized in that: The support assembly (3) is connected to the buffer assembly (2) via a transmission member (4), and the support assembly (3) comprises: a second screw rod (31), the second screw rod (31) being rotatably disposed in the cavity (13); a limit block (32), wherein the limit block (32) is sleeved on the second screw rod (31); Support rods (33), two of which are provided, one end of each of the two support rods (33) being hinged to the two ends of the limit block (32), and the other end of each of the two support rods (33) being in contact with the inner circumference of the injection inner tube (11); A second connecting rod (34), wherein two second connecting rods (34) are provided, and one end of each of the two second connecting rods (34) is slidably connected to one end of the support rod (33); A second moving block (35), the second moving block (35) is slidably connected to the second screw rod (31), and the second moving block (35) is fixedly connected to an end of the second connecting rod (34) away from the support rod (33).

3. A carbon dioxide geological storage injection well structure according to claim 2, characterized in that: The transmission member (4) comprises: a first bevel gear (41), one end of the first bevel gear (41) being fixedly mounted on the upper end of the first screw rod (21); A transmission rod (42), one end of the transmission rod (42) being fixedly connected to the other end of the first bevel gear (41); A second bevel gear (43), wherein one end of the second bevel gear (43) is fixedly connected to the second screw rod (31), and the other end of the second bevel gear (43) is fixedly connected to an end of the transmission rod (42) away from the first bevel gear (41).

4. A carbon dioxide geological storage injection well structure according to claim 2, characterized in that: The injection outer tube (12) and the injection inner tube (11) both comprise a first cement layer (51), a second steel tube layer (52) being fixedly sleeved inside the first cement layer (51), a second cement layer (53) being fixedly sleeved inside the second steel tube layer (52), and a first steel tube layer (54) being fixedly sleeved inside the second cement layer (53).

5. The carbon dioxide geological storage injection well structure according to claim 1, characterized in that: The support components (3) are provided in multiple groups.

6. A carbon dioxide geological storage injection well structure according to claim 2, characterized in that: The support rod (33) is provided with a slide groove (62) along the length direction of the support rod (33), and a guide block (61) is fixedly provided at one end of the second connecting rod (34) close to the slide groove (62), and the guide block (61) is slidably arranged in the slide groove (62).

7. A carbon dioxide geological storage well construction process, based on the injection well structure of claim 3, characterized in that: include: S1. determining the diameters of the injection inner tube (11) and the injection outer tube (12); S2, perfusing the inner injection tube (11) and the outer injection tube (12); S3, determining the positions of the buffer assembly (2), the transmission member (4) and the support assembly (3), and sealing the injection inner tube (11) and the injection outer tube (12); S4. An injection well structure is penetrated into a storage layer (71), wherein the geological storage structure (7) comprises a storage layer (71), a cap rock (72) is fixedly disposed at the upper end of the storage layer (71), and a soil layer (73) is fixedly disposed at the upper end of the cap rock (72).

Images