Sealing device for gaseous hydrogen storage well

Abstract

The invention belongs to the technical field of hydrogen storage, and particularly relates to a sealing device for a gaseous hydrogen storage well. A sealing device is used for sealing any two adjacent casing pipes of a gaseous hydrogen storage well and comprises a plurality of sealing rings which are sequentially arranged in the axial direction, the sealing rings are made of rubber materials with the hydrogen absorption expansion characteristic, and all the sealing rings are arranged to be capable of sequentially absorbing hydrogen to expand for sealing. The risk of hydrogen leakage can be reduced, and safe and efficient storage of hydrogen is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrogen storage, and in particular, relates to a sealing device for a gaseous hydrogen storage well. Background Art

[0002] As a new type of efficient and clean energy, hydrogen energy is the best choice for achieving the strategic goal of "carbon peak and carbon neutrality". The "production, storage, transportation and use" of hydrogen are the four key links in promoting the development of the hydrogen energy industry, among which the "storage" link of hydrogen is an important link between the "production" and "use" of hydrogen.

[0003] High-pressure gaseous hydrogen storage wells use steel casing to store high-pressure gaseous hydrogen. The main storage body is located underground. It has the advantages of small footprint, large storage capacity, and high safety performance. It can effectively promote the safe and efficient storage of hydrogen.

[0004] Hydrogen molecules are small and require high sealing performance for storage containers. High-pressure gaseous hydrogen storage wells are made up of multiple wellbore casings connected together, and the casings are mostly sealed with a single threaded connection, which is a risk point for hydrogen leakage.

[0005] In addition, the main body of the hydrogen storage well is located underground. Once hydrogen leaks at the casing interface, it is difficult to repair and may cause the hydrogen storage well to be shut down, resulting in economic losses. Therefore, it is necessary to set a special sealing structure for the casing interface of the high-pressure gas hydrogen storage well to reduce the risk of hydrogen leakage and achieve safe and efficient storage of hydrogen. Summary of the invention

[0006] In view of the technical problems mentioned above, the present invention aims to propose a sealing device for a gaseous hydrogen storage well, which can reduce the risk of hydrogen leakage and achieve safe and efficient storage of hydrogen.

[0007] According to the present invention, a sealing device is provided for sealing any two adjacent casings of a gaseous hydrogen storage well, comprising a plurality of sealing rings arranged in sequence along the axial direction, wherein the sealing rings are made of a rubber material having the property of expanding upon absorbing hydrogen, and each of the sealing rings is arranged to be able to absorb hydrogen in sequence to expand for sealing.

[0008] In a preferred embodiment provided according to the present invention, a plurality of sealing rings are respectively provided on the upper side and the lower side of the joint between two adjacent sleeves.

[0009] In a preferred embodiment provided according to the present invention, the sealing device further comprises a spacer ring, and a plurality of the spacer rings and the sealing rings are alternately arranged along the axial direction.

[0010] In a preferred embodiment provided according to the present invention, the sealing device further comprises a sealing sleeve, and the sealing sleeve is sleeved on the outside of the sealing ring and the spacer ring.

[0011] In a preferred embodiment provided according to the present invention, the sealing sleeve is mounted on two adjacent sleeves.

[0012] In a preferred embodiment provided according to the present invention, two adjacent sleeves are connected by a coupling, the sealing sleeve is sleeved on the coupling, both axial ends of the sealing sleeve exceed the axial range of the coupling, and the plurality of sealing rings are respectively arranged on the upper and lower sides of the coupling and located between the sleeve and the sealing sleeve.

[0013] In a preferred embodiment provided according to the present invention, a sealing ring is provided on the outer wall of the sealing sleeve.

[0014] In a preferred embodiment provided according to the present invention, the two sealing hoops are respectively arranged at two axial ends of the sealing sleeve, corresponding to the positions of the sealing ring.

[0015] In a specific embodiment, four sealing rings are arranged inside the sealing ring, which are a first sealing ring, a second sealing ring, a third sealing ring, and a fourth sealing ring which are coaxially arranged in sequence.

[0016] A spacer ring is arranged between two adjacent sealing rings, and a spacer ring is arranged at the top of the first sealing ring and the bottom of the fourth sealing ring respectively, and the adjacent sealing rings and the spacer rings are axially abutted against each other.

[0017] In a specific embodiment, both axial ends of the sealing ring are bent inward to form a baffle that can axially abut against the spacer ring. This arrangement can prevent the sealing ring and the spacer ring from axially moving.

[0018] In a preferred embodiment, in the initial state, the size of the first sealing ring is larger than that of the remaining sealing rings. After the sealing hoop is installed, the first sealing ring is in a pressure-bearing state, which is a semi-working state, and the remaining sealing rings are in a non-working state. When hydrogen leaks from the threaded connection between the casing and the coupling and penetrates the hydrogen sealing tape, the first sealing ring contacts the hydrogen and expands by absorbing hydrogen. Under the fixing action of the spacer rings on both sides, the first sealing ring expands radially, and the radial pressure between the first sealing ring and the sealing hoop increases, the sealing performance is improved, and hydrogen sealing is achieved. At this time, the first sealing ring is in a working state.

[0019] As the first seal ring runs longer, it will be permanently deformed, its sealing performance will decline, and the hydrogen seal may eventually fail. After the first seal ring fails, the second seal ring comes into contact with hydrogen, absorbs hydrogen, and expands radially, forming a new hydrogen seal that is in working condition.

[0020] When the second sealing ring fails, the third sealing ring repeats the previous working process.

[0021] In a preferred embodiment provided according to the present invention, the sealing hoop includes four quarter hoops.

[0022] In a preferred embodiment provided according to the present invention, mounting ears are provided at the circumferential ends of the clamps, and the mounting ears of two adjacent clamps are connected by bolts.

[0023] Compared with the prior art, the advantages of the present application are as follows.

[0024] The present invention is provided with a plurality of sealing rings distributed along the axial direction, each of which is made of rubber material that expands upon absorption of hydrogen. Under this arrangement, during operation, the sealing ring closest to the joint of two adjacent casings absorbs hydrogen and expands first to achieve sealing, while the remaining sealing rings are in a non-working state. After the sealing ring reaches the end of its service life, hydrogen passes over the sealing ring and reacts with the next sealing ring, causing the next sealing ring to absorb hydrogen and expand to achieve sealing. Through this arrangement, the service life of the sealing of the present invention can be increased, the long-term use requirements of the hydrogen storage well can be met, and frequent repairs of the sealing device can be avoided.

[0025] The sealing hoop of the present invention is composed of four quarter hoops, so that the sealing ring is evenly stressed in the circumferential direction and has a better sealing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be described below with reference to the accompanying drawings.

[0027] Figure 1 A schematic diagram showing an embodiment of a sealing device according to the present invention installed on a gaseous hydrogen storage well;

[0028] Figure 2 A schematic diagram showing the external structure of the sealing device according to the present invention is shown;

[0029] Figure 3 It shows a schematic structural diagram of a sealing ring and a spacer ring according to the present invention;

[0030] Figure 4 A schematic structural diagram of a sealing ring according to the present invention is shown.

[0031] In the figure:

[0032] 1. Casing;

[0033] 2. Coupling;

[0034] 3. Sealing sleeve;

[0035] 4. Sealing ring; 41. First sealing ring; 42. Second sealing ring; 43. Third sealing ring; 44. Fourth sealing ring;

[0036] 5. Spacer ring;

[0037] 6. Sealing hoop;

[0038] 7. Hoop;

[0039] 8. Install the ears;

[0040] 9. Bolts;

[0041] 100. Sealing device.

[0042] In the present application, all drawings are schematic drawings, which are only used to illustrate the principles of the present invention and are not drawn according to the actual scale. DETAILED DESCRIPTION

[0043] The present invention will be described below with reference to the accompanying drawings.

[0044] It should be noted that, in this application, the direction of the hydrogen storage well of the present invention close to the wellhead is described as "up", "front" or similar terms, that is, Figure 1 The upper side of the well; and the direction close to the bottom of the gas storage well is described as "down", "back" or similar terms, that is, Figure 1 The lower side.

[0045] Figure 1 The structure of the sealing device 100 according to the present invention installed on the hydrogen storage well is shown. Figure 1 As shown, the hydrogen storage well comprises a plurality of casings 1, which are coaxially connected to each other through a coupling 2 to form the entire hydrogen storage well. The sealing device 100 is installed at the joint of two adjacent casings 1 to strengthen the seal between the two adjacent casings 1 of the hydrogen storage well.

[0046] In a preferred embodiment, the main body of the hydrogen storage well is a steel casing 1 with a diameter of 350 mm, and two adjacent casings 1 are connected by a coupling 2. Furthermore, the casing 1 and the coupling 2 are fixed and initially sealed by a threaded connection. The sealing device 100 provided by the present invention is installed on the outside of the coupling 2 to further seal the joint between the coupling 2 and the casing 1.

[0047] The interfaces of adjacent casings 1 of the hydrogen storage well adopt a single sealing measure such as welding or threaded sealing. Since hydrogen molecules are small and have strong escape performance, the interfaces of casing 1 are risk points for micro-leakage of hydrogen under high-pressure storage conditions.

[0048] In a preferred embodiment, after the sleeve 1 is connected by the collar 2, multiple layers of hydrogen sealing tape (not shown) are wrapped around the outside of the collar 2 and the outside of the connection between the collar 2 and the sleeve 1. After the hydrogen sealing tape is set, the sealing device 100 of the present invention is put on.

[0049] According to the present invention, the sealing device 100 comprises a plurality of sealing rings 4 arranged in sequence along the axial direction. The sealing rings 4 are made of a rubber material having the property of expanding by absorbing hydrogen. Each sealing ring 4 is configured to absorb hydrogen in sequence to expand and seal.

[0050] Through the arrangement of multiple sealing rings 4 of the present invention, in the initial state, each sealing ring 4 is in a non-working state, that is, each sealing ring 4 is not subjected to radial compression and cannot play a sealing role, so the life of each sealing ring 4 will not be reduced. When the coupling 2, hydrogen sealing tape, etc. leak, the hydrogen in the hydrogen storage well begins to leak, and the hydrogen contacts the sealing ring 4 closest to the leakage position. The sealing ring 4 begins to absorb hydrogen and expand, thereby being in a working state and playing a sealing role, while the remaining sealing rings 4 are still in a non-working state. When the sealing ring 4 closest to the leakage position fails, hydrogen begins to leak to the next sealing ring 4, and the next sealing ring 4 begins to absorb hydrogen and expand, thereby being in a working state and playing a sealing role.

[0051] The multiple sealing rings 4 of the present invention are turned on in sequence according to the distance from the leakage point from near to far, thereby extending the service life of the entire sealing device 100 and avoiding frequent repairs of the sealing device 100.

[0052] In a specific embodiment, a plurality of sealing rings 4 are provided on the upper and lower sides of the joints of two adjacent sleeves 1. Figure 1 In the embodiment, a plurality of sealing rings 4 are arranged on both the upper and lower sides of the coupling 2.

[0053] In a specific embodiment, the sealing ring 4 is configured as an O-ring and is made of a rubber material that expands by absorbing hydrogen, such as any one of fluororubber, EPDM rubber, acrylonitrile-butadiene rubber, polyisoprene rubber, styrene-butadiene rubber, etc.

[0054] According to the present invention, the sealing device 100 comprises a sealing sleeve 3, which is sleeved on the outside of a sealing ring 4. After the sealing ring 4 absorbs hydrogen and expands, the sealing ring 4 can radially abut against the sealing sleeve 3, so that the sealing ring 4 can seal the annular space between the sealing sleeve 3 and the casing 1.

[0055] In a preferred embodiment, the sealing sleeve 3 is made of a heat-shrinkable high molecular polymer material with hydrogen-blocking properties. By heating the sealing sleeve 3, the sealing sleeve 3 can be tightened to form a sealing effect.

[0056] In a preferred embodiment, the sealing device further comprises a spacer ring 5, and a plurality of spacer rings 5 ​​and sealing rings 4 are alternately arranged along the axial direction. Figure 3 As shown, a plurality of spacer rings 5 ​​and a plurality of sealing rings 4 are alternately and coaxially sleeved on the outside of the sleeve 1 in sequence, and both the spacer rings 5 ​​and the sealing rings 4 are arranged between the sealing sleeve 3 and the sleeve 1 .

[0057] According to the present invention, the spacer ring 5 is made of a polymer material with small deformation.

[0058] Specifically, the spacer ring 5 is made of plastic.

[0059] Furthermore, the spacer ring 5 is made of polytetrafluoroethylene material having hydrogen resistance.

[0060] Through the arrangement of the present invention, the spacer ring 5 can provide an axial abutment force to the sealing ring 4 during the process of hydrogen absorption and expansion, so that the sealing ring 4 can only expand radially, thereby enhancing the sealing effect of the sealing ring 4.

[0061] According to the present invention, combined Figure 1 to Figure 3 As shown, in a specific embodiment, the sealing sleeve 3 is sleeved on two adjacent sleeves 1 .

[0062] Specifically, two adjacent sleeves 1 are connected by a coupling 2, a sealing sleeve 3 is sleeved on the coupling 2, and both axial ends of the sealing sleeve 3 exceed the axial range of the coupling 2. In other words, the axial length of the sealing sleeve 3 is greater than the axial length of the coupling 2.

[0063] A plurality of sealing rings 4 and a plurality of spacer rings 5 ​​are respectively arranged on the upper and lower sides of the coupling 2 and are located between the casing 1 and the sealing sleeve 3. In other words, a plurality of sealing rings 4 and a plurality of spacer rings 5 ​​are arranged between the casing 1 and the portion of the casing 1 that exceeds the axial length range of the coupling 2.

[0064] In a preferred embodiment, the sealing ring 4 or the spacer ring 5 is axially abutted against the coupling 2. That is, the sealing ring 4 and the spacer ring 5 are arranged alternately, when the sealing ring 4 is close to the coupling 2, the sealing ring 4 is axially abutted against the coupling 2; when the spacer ring 5 is close to the coupling 2, the spacer ring 5 is axially abutted against the coupling 2.

[0065] The outer wall of the sealing sleeve 3 is provided with a sealing hoop 6. The two sealing hoops 6 are respectively arranged at the two axial ends of the sealing sleeve 3, corresponding to the positions of the sealing ring 4. In other words, the sealing hoop 6 is sleeved on the outer side of the sealing sleeve 3, which can generate radial pressure for the sealing ring 4 after expansion, thereby enhancing the sealing effect.

[0066] like Figure 4 As shown, the sealing hoop 6 includes four quarter hoops 7. The four hoops 7 are combined to form a ring-shaped sealing hoop 6. Under this arrangement, the sealing hoop 6 is evenly stressed, thereby evenly generating radial pressure on the sealing ring 4, and the sealing effect is good.

[0067] Furthermore, a mounting ear 8 is provided at the circumferential end of the clamp 7 , and the mounting ears 8 of two adjacent clamps 7 are connected by bolts 9 .

[0068] In a specific embodiment, both ends of the circumferential direction of the clamp 7 are bent outward to form a mounting ear 8, and the mounting ears 8 of two adjacent clamps 7 are connected by bolts 9. By adjusting the tightness of the bolts 9, the sealing clamp can form radial pressures of different magnitudes to compress the sealing sleeve 3 and the sealing ring 4, thereby further improving the sealing performance of the sealing device 100.

[0069] like Figure 3 As shown, Figure 3 The sealing device 100 is shown with a sealing ring 4 at a sealing ring 6 below the coupling ring 2. In this embodiment, four sealing rings 4 are arranged inside the sealing ring 6, namely, a first sealing ring 41, a second sealing ring 42, a third sealing ring 43, and a fourth sealing ring 44 which are coaxially arranged in sequence.

[0070] A spacer ring 5 is disposed between two adjacent sealing rings 4 , and a spacer ring 5 is disposed at the top of the first sealing ring 41 and at the bottom of the fourth sealing ring 44 , respectively. Adjacent sealing rings 4 and spacer rings 5 ​​are axially abutted against each other.

[0071] In a specific embodiment, both axial ends of the sealing ring 6 are bent inward to form a baffle (not shown) that can axially abut against the spacer ring 5. This arrangement can prevent the sealing ring 4 and the spacer ring 5 from axially moving.

[0072] In a preferred embodiment, in the initial state, the size of the first sealing ring 41 is larger than the sizes of the remaining sealing rings 4. After the sealing hoop 6 is installed, the first sealing ring 41 is in a pressure-bearing state, which is a semi-working state, and the remaining sealing rings 4 are in a non-working state. When hydrogen leaks from the threaded connection between the casing 1 and the coupling 2 and penetrates the hydrogen sealing tape, the first sealing ring 41 contacts the hydrogen and expands by absorbing hydrogen. Under the fixing action of the spacer rings 5 ​​on both sides, the first sealing ring 41 expands radially, and the radial pressure between the sealing hoop 6 increases, the sealing performance is improved, and hydrogen sealing is achieved. At this time, the first sealing ring 41 is in a working state.

[0073] As the first sealing ring 41 runs longer, it will be permanently deformed, the sealing performance will be reduced, and the hydrogen seal may eventually fail. After the first sealing ring 41 fails, the second sealing ring 42 contacts hydrogen, absorbs hydrogen and expands radially, forming a new hydrogen seal, which is in working condition.

[0074] When the second sealing ring 42 fails, the third sealing ring 43 repeats the previous working process.

[0075] According to the above working process, the sealing ring 4 that is not in contact with hydrogen does not bear pressure, is in a non-working state, and does not undergo permanent deformation. After contacting hydrogen, the sealing ring 4 will absorb hydrogen and expand, and after bearing pressure, it will form a hydrogen seal and be in a working state.

[0076] Therefore, the sealing device 100 provided by the present invention does not need to be manually replaced regularly due to failure of the sealing ring 4 under pressure. When the first sealing ring 41 fails, the second sealing ring 42 automatically takes effect, which is equivalent to automatically replacing the sealing ring 4. Compared with manual replacement of the sealing ring 4, it can save a lot of time and can meet the long-term use requirements of the hydrogen storage well.

[0077] By providing multiple sealing rings 4 and spacer rings 5, the service life of the sealing structure can be greatly improved, effectively solving the problem that the underground structure of the hydrogen storage well cannot be replaced and repaired, effectively reducing the possibility of hydrogen leakage in the hydrogen storage well, and greatly improving the operational safety of the hydrogen storage well.

[0078] It is easy to understand that although four sealing rings 4 are provided in this embodiment, the present invention is not limited to four sealing rings 4, and those skilled in the art can also increase the number of sealing rings 4 based on the present invention and in combination with actual needs.

[0079] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0080] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0081] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0082] Finally, it should be noted that the above is only a preferred embodiment of the present invention and does not constitute any limitation to the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for a person skilled in the art to modify the technical solutions described in the aforementioned embodiments or to replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A sealing device for sealing any two adjacent casings (1) of a hydrogen storage well, characterized in that: It comprises a plurality of sealing rings (4) arranged in sequence along the axial direction, wherein the sealing rings (4) are made of a rubber material having the property of absorbing hydrogen and expanding, and each of the sealing rings (4) is arranged to be able to absorb hydrogen in sequence and expand to perform sealing.

2. The sealing device according to claim 1, characterized in that: A plurality of sealing rings (4) are respectively arranged on the upper side and the lower side of the joint between two adjacent sleeves (1).

3. The sealing device according to claim 2, characterized in that: The sealing device also includes a spacer ring (5), and a plurality of the spacer rings (5) and the sealing rings (4) are alternately arranged along the axial direction.

4. The sealing device according to claim 3, characterized in that: The sealing device further comprises a sealing sleeve (3), wherein the sealing sleeve (3) is sleeved on the outside of the sealing ring (4) and the spacer ring (5).

5. The sealing device according to claim 4, characterized in that: The sealing sleeve (3) is sleeved on two adjacent sleeves (1).

6. The sealing device according to claim 5, characterized in that: Two adjacent sleeves (1) are connected via a coupling (2); the sealing sleeve (3) is sleeved on the coupling (2); both axial ends of the sealing sleeve (3) exceed the axial range of the coupling (2); a plurality of sealing rings (4) are respectively arranged on the upper and lower sides of the coupling (2) and are located between the sleeve (1) and the sealing sleeve (3).

7. The sealing device according to claim 6, characterized in that: A sealing hoop (6) is arranged on the outer wall of the sealing sleeve (3).

8. The sealing device according to claim 7, characterized in that: The two sealing hoops (6) are respectively arranged at two axial ends of the sealing sleeve (3), corresponding to the positions of the sealing ring (4).

9. The sealing device according to claim 7 or 8, characterized in that: The sealing hoop (6) comprises four quarter hoops (7).

10. The sealing device according to claim 9, characterized in that: A mounting ear (8) is provided at the circumferential end of the clamp (7), and the mounting ears (8) of two adjacent clamps (7) are connected by bolts.

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