A ring-shaped electrolytic water hydrogen production device for abandoned oil wells

Abstract

The application relates to a ring-shaped electrolytic water hydrogen production device for a waste oil well, which comprises an outer cover with a ring-shaped structure, the outer cover is provided with cathode electrode sheets in the circumferential direction, the middle part of the outer cover is detachably connected with an inner cover, the inner cover is provided with anode electrode sheets in the circumferential direction, the surfaces of the anode electrode sheets and the cathode electrode sheets are loaded with electrolytic catalysts, the outer cover is provided with a ring-shaped structure of a partition plate in the axial direction, and the outer cover and the inner cover are respectively provided with power supply holes and exhaust holes which are communicated with the cathode electrode sheets and the anode electrode sheets. The application is a novel electrolytic water hydrogen production device with an open structure, wherein the anode electrode sheets and the cathode electrode sheets are exposed and directly contacted with waste well water, the problem of flow field flow channel blockage is directly avoided from the structure, the problem of strict dependence of an existing electrolytic tank on water quality is solved, and meanwhile, the open structure design can improve flexible adaptability to different pressures, so that the device can stably operate in different downhole environments.

Description

Technical Field

[0001] This invention relates to the field of water electrolysis for hydrogen production technology, specifically to a ring-shaped water electrolysis device for producing hydrogen from abandoned oil wells. Background Technology

[0002] With the long-term development of the energy extraction industry, a large number of abandoned oil wells have been left idle and abandoned due to resource depletion or limited extraction conditions, resulting not only in resource waste but also environmental governance pressure. Meanwhile, water electrolysis for hydrogen production, as a clean and efficient method of green hydrogen preparation, has become one of the core technologies for energy transformation. If natural water bodies within idle or abandoned well sites can be used for hydrogen electrolysis, the dual resource utilization of "idle space + water resources" can be achieved, possessing significant resource value, economic benefits, and environmental benefits.

[0003] However, existing commercial electrolyzers are difficult to operate normally in complex downhole environments. This is because current electrolyzers have stringent water quality requirements, relying on high-purity water. Furthermore, to improve electrolysis efficiency, the electrolyte flow field and channels are mostly designed as straight or point-like structures. Downhole water generally contains impurities such as silt, minerals, organic matter, drilling fluid residue, or fracturing fluid residue. If commercial electrolyzers are directly applied to abandoned wells containing impurities, these impurities will quickly deposit and clog the flow field and channels as the water flows through them, severely affecting electrolysis efficiency. In addition, the pressure fluctuations in downhole spaces vary greatly depending on the type and depth of the well. Current electrolyzers are mostly relatively closed structures with high requirements for the working environment, making them unsuitable for various downhole environments and unable to meet their stable operation needs. Summary of the Invention

[0004] The purpose of this invention is to provide a ring-shaped water electrolysis hydrogen production device for abandoned oil wells to address the shortcomings of existing technologies. This device is adaptable to various complex downhole environments, requires no pure water pretreatment, can operate stably within a wide pressure range, and can produce qualified purity hydrogen. It solves the problems of traditional commercial electrolyzers that rely on high-purity water, cannot be used in abandoned wells containing impurities, have poor hydrogen production stability, and cannot meet the requirements for stable operation.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: An annular water electrolysis hydrogen production device for abandoned oil wells includes an annular outer cover with a cathode electrode plate circumferentially arranged on the outer cover. An inner cover is detachably connected to the middle of the outer cover, with an anode electrode plate circumferentially arranged on the inner cover. Both the anode and cathode electrode plates are loaded with an electrolysis catalyst. An annular partition plate extends axially from the outer cover to separate the anode and cathode electrode plates. An external power supply hole and an external vent hole are respectively opened on the outer cover and are respectively opened on the inner cover and are respectively opened on the inner cover and are respectively connected to the anode electrode plate.

[0006] Furthermore, the cathode electrode sheet is detachably connected to the outer cover.

[0007] Furthermore, the outer cover has a cathode connection groove, and a circular cathode connector is provided in the cathode connection groove. The cathode connector has a cathode slot for inserting a cathode electrode plate. The outer cover has an external connection hole in the circumferential direction, and a cathode connection hole is provided on the corresponding cathode connector. The cathode electrode plate has a cathode insertion hole. The outer cover, cathode connector and cathode electrode plate are relatively fixed by fasteners inserted into the external connection hole, cathode connection hole and cathode insertion hole.

[0008] Furthermore, the cathode slot is spiral-shaped, and the corresponding cathode electrode sheet has a spiral structure.

[0009] Furthermore, the anode electrode sheet is detachably connected to the inner cover.

[0010] Furthermore, the inner cover has an anode slot for inserting the anode electrode plate, and an inner connecting hole is provided in the circumferential direction of the inner cover. Correspondingly, an anode insertion hole is provided on the anode electrode plate. The inner cover and the anode electrode plate are relatively fixed by fasteners inserted into the inner connecting hole and the anode insertion hole.

[0011] Furthermore, the anode slot is spiral-shaped, and the corresponding anode electrode sheet has a spiral structure.

[0012] Furthermore, the inner cover has an annular inner groove in the circumferential direction, and an inner sealing ring is provided on the inner groove.

[0013] Furthermore, the outer cover has an annular outer groove in the circumferential direction, and an outer sealing ring is provided on the outer groove.

[0014] Furthermore, the sidewall of the partition is provided with through holes in the circumferential direction, and the sidewall of the partition is covered with a diaphragm in the circumferential direction.

[0015] Compared with the prior art, the beneficial effects of the present invention are: This invention discloses a novel open-structure water electrolysis hydrogen production device. Both the anode and cathode electrodes are exposed and in direct contact with the waste well water, structurally avoiding flow channel blockage and resolving the stringent water quality requirements of existing electrolyzers. The open structure also enhances adaptability to different pressures, enabling stable operation in various downhole environments. Furthermore, the anode electrode is located in the inner ring, and the cathode electrode in the outer ring, separated by a ring-shaped partition, effectively separating the inner anode chamber from the outer cathode chamber, ensuring reliable separation of hydrogen and oxygen during electrolysis. Both the inner and outer anode electrodes are helical, maximizing the contact area between the electrodes and the water while ensuring effective separation by the partition. This adapts to various downhole space sizes and, combined with highly efficient electrolysis catalysts, significantly improves electrolysis efficiency. Furthermore, the entire unit features a detachable, segmented structure, allowing for flexible assembly according to well depth and adjustment of the electrolysis scale as needed. When a component reaches the end of its service life, it can be easily disassembled and replaced individually. The versatile materials and structural design ensure the stability and durability of the water electrolysis hydrogen production unit during long-term downhole operation.

[0016] This invention transforms various idle underground spaces into green hydrogen production sites, while utilizing natural underground water resources to achieve dual resource utilization of "idle space + water body". This reduces the site and water resource costs for green hydrogen production, and has significant economic, environmental, and industrial promotion value. It becomes the key to realizing the resource-based hydrogen production of various underground spaces, and is of great significance to promoting the utilization of idle resources and the development of the green hydrogen industry. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the upper part of the present invention; Figure 2 This is a schematic diagram of the overall structure of the lower part of the present invention; Figure 3 This is a schematic diagram of the structure from a low angle of view of the present invention; Figure 4 This is a cross-sectional schematic diagram of the internal connecting hole and the anode insertion hole in this invention; Figure 5 This is a cross-sectional schematic diagram of the external connection hole, cathode connection hole, and cathode insertion hole in this invention; Figure 6 This is a cross-sectional schematic diagram of the external exhaust port in this invention; Figure 7 This is a cross-sectional schematic diagram of the external power-conducting hole in this invention; Figure 8 This is a cross-sectional schematic diagram of the internal exhaust port and internal power supply port in this invention; Figure 9This is a schematic diagram of the upper part of the outer cover in this invention; Figure 10 This is a schematic diagram of the lower part of the outer cover in this invention; Figure 11 This is a schematic diagram of the upper part of the inner cover in this invention; Figure 12 This is a schematic diagram of the lower part of the inner cover in this invention; Figure 13 This is a schematic diagram of the upper part of the cathode connector in this invention; Figure 14 This is a schematic diagram of the lower part of the cathode connector in this invention; Figure 15 This is a schematic diagram showing the positional relationship between the cathode electrode and the anode electrode in this invention.

[0018] The attached figures are labeled as follows: 1. Outer cover; 11. Outer groove; 12. Outer power-through hole; 13. Outer vent hole; 14. Outer connection hole; 15. Cathode connection groove; 2. Inner cover; 21. Anode slot; 22. Inner groove; 23. Inner power-through hole; 24. Inner vent hole; 25. Inner connection hole; 3. Cathode connector; 31. Cathode connection hole; 32. Cathode slot; 33. Cathode connection power-through hole; 4. Partition; 41. Through hole; 5. Anode electrode plate; 51. Anode insertion hole; 6. Cathode electrode plate; 61. Cathode insertion hole; 7. Outer sealing ring; 8. Inner sealing ring. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0020] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0021] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They 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. Therefore, they should not be construed as limitations on this application.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0023] For easier understanding, please refer to Figures 1 to 15 This embodiment provides a ring-shaped water electrolysis hydrogen production device for abandoned oil wells, including a ring-shaped outer cover 1 and a columnar inner cover 2 detachably connected to the central cavity of the outer cover 1. The inner cover 2 has an annular groove 22 in the circumferential direction, and a fluororubber inner sealing ring 8 is fixedly fitted inside the groove 22, achieving a sealed fit between the inner cover 2 and the outer cover 1 through the inner sealing ring 8. The outer cover 1 has an annular outer groove 11 in the circumferential direction, and a fluororubber outer sealing ring 7 is fixedly fitted inside the outer groove 11, achieving a sealed fit between the entire device and the downhole space through the outer sealing ring 7. Preferably, the outer cover 1 and the inner cover 2 are coaxially arranged; the outer cover 1 and the inner cover 2 are made of high-pressure corrosion resistant materials, such as titanium alloy, stainless steel, corrosion-resistant alloy, or polymer composite materials, to withstand the high-pressure environment downhole. The lower part of the outer cover 1 is detachably connected to a cathode electrode plate 6 in the circumferential direction, and the lower part of the inner cover 2 is detachably connected to an anode electrode plate 5 in the circumferential direction. The lower parts of both the anode electrode plate 5 and the cathode electrode plate 6 extend axially to contact the downhole water. The surfaces of both the anode electrode plate 5 and the cathode electrode plate 6 are loaded with an electrolytic catalyst. The electrolytic catalyst is at least one of the following: Raney nickel, platinum-based catalyst, nickel-based composite catalyst, cobalt-based composite catalyst, iron-based composite catalyst, molybdenum-based composite catalyst, copper-based composite catalyst, and chromium-based composite catalyst. It possesses good corrosion resistance and electrolytic catalytic activity, and can adapt to long-term electrolysis operations in complex downhole water conditions. More preferably, the electrolytic catalyst is a graphene-doped nickel-based catalyst (NiS) to improve electron transport efficiency under high-pressure conditions. Furthermore, the surfaces of the anode electrode plate 5 and the cathode electrode plate 6 can be provided with recessed or uneven structures to support the electrolytic catalytic material, thereby enhancing the stability of the catalytic material loading and the contact area with the water.

[0024] A circular baffle 4 extends axially from the lower part of the outer cover 1. The axial length of the baffle 4 is greater than the axial length of the anode electrode 5 and the cathode electrode 6, separating the anode electrode 5 and the cathode electrode 6. Multiple through holes 41 are formed circumferentially on each sidewall of the baffle 4, serving as ion exchange channels to ensure ion transport during electrolysis. Each sidewall of the baffle 4 is covered with a fouling-resistant membrane (not shown in the figure), which covers the through holes 41 on the baffle 4. The baffle 4 and the membrane separate the anode electrode 5 and the cathode electrode 6, creating an outer cathode cavity and an inner anode cavity, thus isolating hydrogen and oxygen generated during electrolysis and preventing gas mixing that could lead to safety hazards. Preferably, the separator 4 is made of salt-resistant PP material, and the pore size of the through hole 41 is 0.8 mm, which is suitable for the ion transport characteristics of high-salt solutions. The separator can be a PPS separator, a Zirfon separator, an asbestos separator, or other acid and alkali resistant and pollution-resistant polymer separators. More preferably, the combination design of the salt-resistant material of the separator 4, the Zirfon-enhanced separator, and the NiMo composite catalyst maintains catalytic activity and stability under high-salt conditions, effectively suppresses the interference of high concentrations of salt and impurities in the formation water of the well on the electrolysis process, and ensures long-term stable hydrogen production in high-salt complex water bodies, meeting the hydrogen production needs of the high-salt environment of the well.

[0025] The outer cover 1 has an external power-conducting hole 12 and an external vent hole 13, which are respectively connected to the cathode electrode plate 6. The inner cover 2 has an internal power-conducting hole 23 and an internal vent hole 24, which are respectively connected to the anode electrode plate 5. The external power-conducting hole 12 and the internal power-conducting hole 23 are respectively connected to the power supply system, and the external vent hole 13 and the internal vent hole 24 are respectively connected to the gas collection system. The two power-conducting holes are used to connect the wires to supply power to the electrode plates, and the two vent holes are used to collect the hydrogen and oxygen generated by electrolysis, respectively. The power supply system provides a working voltage range of 1.0V to 5.0V, which can achieve efficient electrolysis without a high-voltage environment. The power supply system can be equipped with a photovoltaic power supply unit, a downhole cable power supply unit, or an energy storage power supply unit, and has a voltage stabilization function (voltage fluctuation range does not exceed ±0.1V), which can adapt to various unstable power supply environments in wells. The gas collection system includes a gas outlet channel connected to the outer cathode cavity, a drying component, and a filter component. These components collect hydrogen produced by electrolysis and remove water vapor and trace impurities from the hydrogen, ensuring a hydrogen purity of at least 95%. The system also includes an oxygen collection module connected to the inner anode cavity, enabling coordinated hydrogen and oxygen recovery. Wires (not shown in the figure) are connected to the anode electrode 5 and cathode electrode 6, respectively. These wires are connected to an external power source through corresponding inner and outer power holes 23 and 12.

[0026] The lower part of the outer cover 1 has an annular cathode connection groove 15, and a circular cathode connector 3 is detachably connected to the cathode connection groove 15. The cathode connector 3 can be inserted into the cathode connection groove 15. The lower part of the cathode connector 3 has a cathode slot 32 for inserting the cathode electrode plate 6. Furthermore, the cathode slot 32 is spiral-shaped, corresponding to the spiral structure of the cathode electrode plate 6. The cathode connector 3 has a vertical cathode connection power hole 33, which communicates with the external power hole 12. The wires of the cathode electrode plate 3 are connected to the external power source after passing through the cathode connection power hole 33 and the external power hole 12. The lower part of the outer cover 1 has multiple external connection holes 14 spaced apart in the circumferential direction. Correspondingly, the middle part of the cathode connector 3 has a cathode connection hole 31 in the circumferential direction. The upper part of the cathode electrode plate 6 has a cathode insertion hole 61 in the circumferential direction. The upper part of the cathode connector 3 is inserted into the cathode connection groove 15 at the lower part of the outer cover 1, and the upper part of the cathode electrode plate 6 is inserted into the cathode slot 32 at the lower part of the cathode connector 3. Fasteners (such as screws) are driven into the outer connection hole 14, cathode connection hole 31, and cathode insertion hole 61 to achieve relative fixation of the outer cover 1, cathode connector 3, and cathode electrode plate 6. The lower part of the inner cover 2 has an anode slot 21 for inserting the anode electrode plate 5. Furthermore, the anode slot 21 is spiral-shaped, corresponding to the spiral structure of the anode electrode plate 5. The lower part of the inner cover 2 has multiple internal connection holes 25 spaced circumferentially, corresponding to the anode insertion hole 51 on the upper part of the anode electrode plate 5. The upper part of the anode electrode plate 5 is inserted into the anode slot 21 at the lower part of the inner cover 2, and fasteners (such as screws) are driven into the internal connection holes 25 and anode insertion holes 51 to achieve relative fixation of the inner cover 2 and anode electrode plate 5. The anode electrode plate 5, cathode electrode plate 6, and partition plate 4 are coaxially arranged.

[0027] The installation method of the present invention is as follows: insert the anode electrode plate 5 into the anode slot 21 at the bottom of the inner cover 2, and fix the anode electrode plate 5 and the inner cover 2 relative to each other with fasteners; insert the cathode electrode plate 6 into the cathode slot 32 at the bottom of the cathode connector 3, and insert the cathode connector 3 with the cathode electrode plate 6 inserted into the cathode connection groove 15 at the bottom of the outer cover 1, and fix the cathode electrode plate 6, the cathode connector 3 and the outer cover 1 relative to each other with fasteners; at this time, the partition plate 4 with the diaphragm attached separates the cathode electrode plate 6 located in the outer ring from the anode electrode plate 5 located in the inner ring; install the inner cover 2 with the anode electrode plate 5 fixed in it into the cavity area in the middle of the outer cover 1, and fix the outer cover 1 and the inner cover 2 in a sealed manner through the inner sealing ring 8 on the inner cover 2, thus forming a complete water electrolysis hydrogen production device.

[0028] Although the present invention has been described using the above preferred embodiments, it is not intended to limit the scope of protection of the present invention. Any changes and modifications made by those skilled in the art to the above embodiments without departing from the spirit and scope of the present invention shall still fall within the scope of protection of the present invention.

Claims

1. A ring-type water electrolysis hydrogen production device for abandoned oil wells, characterized in that, The outer cover (1) has a ring-shaped structure. The outer cover (1) has a cathode electrode plate (6) in the circumferential direction. The inner cover (2) is detachably connected to the middle of the outer cover (1). The inner cover (2) has an anode electrode plate (5) in the circumferential direction. The surfaces of the anode electrode plate (5) and the cathode electrode plate (6) are loaded with an electrolytic catalyst. The outer cover (1) has a ring-shaped partition plate (4) in the axial direction for separating the anode electrode plate (5) and the cathode electrode plate (6). The outer cover (1) has an external power-through hole (12) and an external exhaust hole (13) that are respectively connected to the cathode electrode plate (6). The inner cover (2) has an internal power-through hole (23) and an internal exhaust hole (24) that are respectively connected to the anode electrode plate (5).

2. The annular water electrolysis hydrogen production device for abandoned oil wells according to claim 1, characterized in that, The cathode electrode sheet (6) is detachably connected to the outer cover (1).

3. The annular water electrolysis hydrogen production device for abandoned oil wells according to claim 2, characterized in that, The outer cover (1) has a cathode connection groove (15), and a cathode connector (3) with a circular structure is provided in the cathode connection groove (15). The cathode connector (3) has a cathode slot (32) for inserting the cathode electrode plate (6). The outer cover (1) has an external connection hole (14) in the circumferential direction. The cathode connector (3) has a cathode connection hole (31) in the corresponding direction. The cathode electrode plate (6) has a cathode insertion hole (61). The outer cover (1), the cathode connector (3), and the cathode electrode plate (6) are relatively fixed by fasteners inserted into the external connection hole (14), the cathode connection hole (31), and the cathode insertion hole (61).

4. The annular water electrolysis hydrogen production device for abandoned oil wells according to claim 3, characterized in that, The cathode slot (32) is spiral-shaped, and the corresponding cathode electrode sheet (6) is spiral-shaped.

5. The annular water electrolysis hydrogen production device for abandoned oil wells according to claim 1, characterized in that, The anode electrode plate (5) is detachably connected to the inner cover (2).

6. The annular water electrolysis hydrogen production device for abandoned oil wells according to claim 5, characterized in that, The inner cover (2) is provided with an anode slot (21) for inserting the anode electrode plate (5). The inner cover (2) is provided with an inner connection hole (25) in the circumferential direction. The anode electrode plate (5) is provided with an anode insertion hole (51). The inner cover (2) and the anode electrode plate (5) are relatively fixed by fasteners inserted into the inner connection hole (25) and the anode insertion hole (51).

7. The annular water electrolysis hydrogen production device for abandoned oil wells according to claim 6, characterized in that, The anode slot (21) is spiral-shaped, and the corresponding anode electrode plate (5) is spiral-shaped.

8. The annular water electrolysis hydrogen production device for abandoned oil wells according to claim 1, characterized in that, The inner cover (2) has an annular inner groove (22) in the circumferential direction, and an inner sealing ring (8) is provided on the inner groove (22).

9. The annular electrolytic water electrolysis hydrogen production device for abandoned oil wells according to claim 1, characterized in that, The outer cover (1) has an annular outer groove (11) in the circumferential direction, and an outer sealing ring (7) is provided on the outer groove (11).

10. The annular electrolytic water electrolysis hydrogen production device for abandoned oil wells according to claim 1, characterized in that, The sidewall of the partition (4) has a through hole (41) in the circumferential direction, and the sidewall of the partition (4) is covered with a diaphragm in the circumferential direction.

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