Electric field enhanced underground hydrogen storage system and method

Abstract

This invention belongs to the field of underground hydrogen storage engineering technology, specifically disclosing an electric field-enhanced underground hydrogen storage system and method. It addresses the problems of low injection-production efficiency and small hydrogen storage capacity in conventional injection-production methods used in current underground hydrogen storage projects. The system includes an injection-production well, a first electrode column module, and a second electrode column module. The injection-production well is used for hydrogen injection and production. The first electrode column module represents one type of electrode in the electric field, and the second electrode column module represents the other, opposite electrode. The first and second electrode column modules carry equal amounts of opposite charges and are located on opposite sides of the injection-production well at the same distance, forming a non-uniform electric field in the reservoir. This invention applies an additional electric field to polarize hydrogen molecules, generating induced dipoles. Under the influence of the electric field, the hydrogen flow velocity is increased, thus increasing the hydrogen storage capacity and improving hydrogen injection-production efficiency.

Description

Technical Field

[0001] This invention belongs to the field of underground hydrogen storage engineering technology, and particularly relates to an electric field enhanced underground hydrogen storage system and method. Background Technology

[0002] Traditional hydrogen storage methods mainly include high-pressure storage tanks, cryogenic liquid hydrogen storage, and chemical storage (such as metal hydrides). While these methods have achieved short-term hydrogen storage to some extent, they have significant limitations. High-pressure storage tanks require complex equipment to maintain a high-pressure state and have limited storage capacity; cryogenic liquid hydrogen storage requires extremely low temperatures, resulting in high energy consumption and complex technology; and while chemical storage offers better stability, the efficiency of hydrogen release and re-adsorption processes is low. Therefore, traditional hydrogen storage methods are insufficient to meet the future demand for large-scale, long-term hydrogen storage under the goal of zero carbon emissions.

[0003] Underground hydrogen storage, as an emerging hydrogen storage technology, is gradually gaining attention. The core idea of ​​this technology is to utilize underground geological structures (such as salt caverns, depleted oil and gas reservoirs, and aquifers) as storage media, injecting hydrogen underground for long-term storage and flexibly extracting it during peak energy demand periods or special times. Underground hydrogen storage has many significant advantages. First, its storage capacity far exceeds that of traditional methods, meeting the hydrogen storage needs of industrial-scale operations. Second, the underground storage environment has natural isolation and stability, effectively reducing the risk of hydrogen leakage. Furthermore, the integration of underground hydrogen storage with existing oil and gas storage and transportation infrastructure further reduces the cost of technological upgrades and application barriers. Therefore, underground hydrogen storage technology shows broad application prospects in the future energy structure transformation.

[0004] Despite the numerous advantages of underground hydrogen storage, a series of technical challenges remain. Among these, improving the hydrogen injection-production rate and storage efficiency is a key issue. In underground hydrogen storage projects, the conventional injection method involves pressurizing hydrogen using surface equipment and injecting it into the formation through a well. The conventional extraction method involves depressurizing and recovering the hydrogen using the reservoir pressure through the well. This conventional hydrogen injection-production method results in a relatively low hydrogen flow velocity, and hydrogen can only be stored at its density under the conditions of formation temperature and pressure, leading to a limited storage capacity. Summary of the Invention

[0005] One objective of this invention is to provide an electric field-enhanced underground hydrogen storage system that effectively solves the problems of low injection and extraction efficiency and small hydrogen storage capacity in conventional injection and extraction methods in current underground hydrogen storage projects.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] An electric field enhanced underground hydrogen storage system includes an injection-production well, a first electrode column module, and a second electrode column module. The injection-production well is used for hydrogen injection and extraction. The first electrode column module represents one type of electrode in the electric field, and the second electrode column module represents another opposite electrode in the electric field. The first and second electrode column modules carry equal amounts of opposite charges and are located on opposite sides of the injection-production well at the same distance, forming a non-uniform electric field in the reservoir.

[0008] Furthermore, the injection-production well extends deep into the reservoir from the surface well site, and is located in the middle of the entire electric field enhanced underground hydrogen storage system.

[0009] The first electrode column module is located on one side of the injection-production well, and its height is equal to the reservoir thickness of the underground hydrogen storage structure.

[0010] The second electrode column module is located on the other side of the injection-production well opposite to the first electrode column module, and its height is equal to the reservoir thickness of the underground hydrogen storage structure.

[0011] Another objective of this invention is to provide an electric field-enhanced underground hydrogen storage method, employing the electric field-enhanced underground hydrogen storage system described in the above embodiments. Hydrogen is injected into the reservoir of the underground hydrogen storage structure through injection-production wells. During the injection process, the hydrogen is polarized in the non-uniform electric field formed by the first electrode column module and the second electrode column module. The positive and negative charge centers of the hydrogen no longer coincide, generating induced dipoles. Hydrogen molecules form equal amounts of induced charges of opposite signs. The two induced charges are subjected to electrostatic attraction and electrostatic repulsion forces of different magnitudes and opposite directions by the non-uniform electric field, causing the hydrogen to form a directional acceleration moving towards the first electrode column module or the second electrode column module.

[0012] Hydrogen is extracted to the surface through injection wells. During the extraction process, the positive and negative poles of the non-uniform electric field are changed at a set frequency, causing the hydrogen to generate directional acceleration toward the injection wells.

[0013] Furthermore, the transformation of the positive and negative poles of the non-uniform electric field represents the positive and negative transformation of the charge properties of the first electrode post module and the second electrode post module.

[0014] Furthermore, during the injection process, the hydrogen will enter the reservoir half-zone controlled by the first electrode column module and the reservoir half-zone controlled by the second electrode column module through the injection and production wells, respectively. At this time, the first electrode column module displays a positive charge, and the second electrode column module displays a negative charge.

[0015] Hydrogen gas is polarized in the non-uniform electric field formed by the first electrode post module and the second electrode post module. The positive and negative charge centers of hydrogen gas no longer coincide, generating induced dipoles. Hydrogen molecules form equal amounts of induced charges of opposite signs, generating positive charges along the direction of the electric field lines and negative charges along the opposite direction of the electric field lines.

[0016] In the reservoir half-region controlled by the first electrode post module, the electric field density is greater at the location of the negative charge of hydrogen molecules and smaller at the location of the positive charge. Therefore, the electrostatic attraction of the negative charge of hydrogen molecules is greater than the electrostatic repulsion of the positive charge. The net force on the hydrogen molecules is not zero, and the direction of the net force is towards the first electrode post module. As a result, the hydrogen gas accelerates towards the first electrode post module, and the flow velocity of the hydrogen gas increases.

[0017] In the reservoir half-region controlled by the second electrode post module, the electric field density is greater at the location of the positive charge of hydrogen molecules and smaller at the location of the negative charge. Therefore, the electrostatic attraction of the positive charge of hydrogen molecules is greater than the electrostatic repulsion of the negative charge. The net force on the hydrogen molecules is not zero, and the direction of the net force is towards the second electrode post module. As a result, the hydrogen gas accelerates towards the second electrode post module, and the flow velocity of the hydrogen gas increases.

[0018] Therefore, during the hydrogen injection process, the hydrogen in the reservoir half-region controlled by the first electrode column module will accelerate towards the first electrode column module, and the hydrogen in the reservoir half-region controlled by the second electrode column module will accelerate towards the second electrode column module.

[0019] Furthermore, during the hydrogen extraction process, hydrogen will enter the injection and production wells from the reservoir half-zone controlled by the first electrode column module and the reservoir half-zone controlled by the second electrode column module, and then be recovered to the surface well site.

[0020] The positive and negative poles of the non-uniform electric field are switched so that the first electrode post module displays a negative charge and the second electrode post module displays a positive charge. At this time, the hydrogen gas is still in the polarization state before the electric field is switched.

[0021] In the reservoir half-region controlled by the first electrode column module, the electric field density is greater where the hydrogen molecules are negatively charged, and smaller where the hydrogen molecules are positively charged. Therefore, the electrostatic repulsion force on the negatively charged hydrogen molecules is greater than the electrostatic attraction force on the positively charged ones. The net force on the hydrogen molecules is not zero, and the direction of the net force is towards the injection-production well. As a result, the hydrogen gas accelerates towards the injection-production well, and the flow velocity of the hydrogen gas increases.

[0022] In the reservoir half-region controlled by the second electrode column module, the electric field density is greater at the location of the positive charge of hydrogen molecules and smaller at the location of the negative charge. Therefore, the electrostatic repulsion force on the positive charge of hydrogen molecules is greater than the electrostatic attraction force on the negative charge. The net force on the hydrogen molecules is not zero, and the direction of the net force is towards the injection-production well. As a result, the hydrogen gas accelerates towards the injection-production well, and the flow velocity of the hydrogen gas increases.

[0023] Therefore, within a short period of time during which the positive and negative poles of the non-uniform electric field are switched, hydrogen in the reservoir half-region controlled by the first electrode column module will accelerate towards the injection-production well, and hydrogen in the reservoir half-region controlled by the second electrode column module will also accelerate towards the injection-production well; the short period of time refers to no more than 10 seconds. -12 Second.

[0024] Furthermore, after a prolonged period of alternating the positive and negative poles of the non-uniform electric field, the hydrogen gas will repolarize according to the current electric field distribution, generating positive charges along the direction of the electric field lines and negative charges along the opposite direction. At this time, the force state of the hydrogen gas is similar to that of the hydrogen gas during the injection process, and the hydrogen gas tends to flow towards the first electrode post module and the second electrode post module; the prolonged period is greater than 10. -12 Seconds; During the hydrogen extraction process, in order to prevent the hydrogen from flowing towards the first electrode column module and the second electrode column module, it is necessary to change the positive and negative poles of the non-uniform electric field again so that the hydrogen always accelerates towards the injection and production well.

[0025] Therefore, hydrogen needs to be extracted at a rate of 10 12 The frequency of Hz changes the positive and negative poles of the non-uniform electric field, preventing hydrogen from flowing towards the first electrode column module and the second electrode column module, and maintaining the accelerated flow of hydrogen towards the injection and production well.

[0026] Compared with the prior art, the beneficial technical effects of the present invention are:

[0027] This invention applies an additional electric field by symmetrically arranging a first electrode column module and a second electrode column module with equal and opposite charges on both sides of the injection and production well. This polarizes the hydrogen molecules, generating induced dipoles. Consequently, under the influence of the electric field, the hydrogen flow velocity is increased, and the hydrogen storage capacity is enhanced, thus improving hydrogen injection and production efficiency. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the equipotential lines distribution of a non-uniform electric field.

[0029] Figure 2 This is a schematic diagram of the forces acting on hydrogen molecules in a non-uniform electric field during hydrogen injection.

[0030] Figure 3 This is a schematic diagram of the forces acting on hydrogen molecules during a short period of time when the direction of the non-uniform electric field changes during hydrogen extraction.

[0031] Figure 4 This is a schematic diagram of the forces acting on hydrogen molecules after a long period of time during the hydrogen extraction process, when the direction of the non-uniform electric field is changed. Detailed Implementation

[0032] Example 1: The electric field enhanced underground hydrogen storage system includes injection and production wells, a first electrode column module, and a second electrode column module.

[0033] Injection and production wells are used for the injection and extraction of hydrogen. These wells extend from the surface well site deep into the reservoir and are located in the middle of the entire electric field-enhanced underground hydrogen storage system.

[0034] The first electrode column module represents one type of electrode in the electric field, such as a positive or negative electrode; the first electrode column module is located on one side of the injection-production well, and its height is equal to the reservoir thickness of the underground hydrogen storage structure. The second electrode column module represents another opposite electrode in the electric field, such as a negative or positive electrode; the second electrode column module is located on the other side of the injection-production well opposite to the first electrode column module, and its height is equal to the reservoir thickness of the underground hydrogen storage structure.

[0035] The first and second electrode post modules, carrying equal amounts of opposite charges, are located on opposite sides at the same distance from the injection-production well, creating a non-uniform electric field in the reservoir. In this embodiment, both the first and second electrode post modules are approximately 300 meters from the injection-production well. Figure 1 As shown, the closer the region is to the first electrode post module and the second electrode post module, the denser the electric field lines, the higher the electric potential, and the greater the electric force on the charge.

[0036] In this embodiment, both the first electrode post module and the second electrode post module include electrode posts made of steel and power supply equipment. The power supply equipment energizes the electrode posts, giving them positive and negative poles. When the power supply equipment is an AC power source, the positive and negative poles of the electrode posts can be alternately switched.

[0037] Example 2: Electric field enhanced underground hydrogen storage method, using the electric field enhanced underground hydrogen storage system described in Example 1. In the underground hydrogen storage project, hydrogen is injected into the reservoir of the underground hydrogen storage structure through injection-production wells.

[0038] (1) During hydrogen injection, hydrogen enters the reservoir half-region controlled by the first electrode column module and the reservoir half-region controlled by the second electrode column module through the injection and production wells, respectively. At this time, the first electrode column module displays a positive charge, and the second electrode column module displays a negative charge. Hydrogen is polarized in the non-uniform electric field formed by the first and second electrode column modules, and the positive and negative charge centers of hydrogen no longer coincide, generating induced dipoles. Hydrogen molecules form equal amounts of induced charges of opposite signs, generating positive charges along the direction of the electric field lines and negative charges along the opposite direction of the electric field lines, such as... Figure 2 As shown.

[0039] Within the reservoir half-region controlled by the first electrode post module, the electric field density is higher where hydrogen molecules are negatively charged, and lower where they are positively charged. Therefore, the electrostatic attraction experienced by the negatively charged hydrogen molecules is greater than the electrostatic repulsion experienced by the positively charged ones. The net force on the hydrogen molecules is not zero, and its direction is towards the first electrode post module. This results in an acceleration of the hydrogen gas towards the first electrode post module, increasing its flow velocity.

[0040] In the reservoir half-region controlled by the second electrode post module, the electric field density is higher where the hydrogen molecules are positively charged, and lower where the molecules are negatively charged. Therefore, the electrostatic attraction of the positively charged hydrogen molecules is greater than the electrostatic repulsion of the negatively charged ones. The net force on the hydrogen molecules is not zero, and the direction of the net force is towards the second electrode post module. This results in an acceleration of the hydrogen gas towards the second electrode post module, increasing the hydrogen flow velocity.

[0041] Therefore, during hydrogen injection, the hydrogen in the reservoir half-region controlled by the first electrode column module will accelerate towards the first electrode column module, and the hydrogen in the reservoir half-region controlled by the second electrode column module will accelerate towards the second electrode column module. The resultant force on the hydrogen not only causes it to accelerate towards the electrode columns, increasing its flow velocity, but also compresses the hydrogen in the reservoir, increasing its hydrogen storage capacity.

[0042] (2) During the extraction process, hydrogen will enter the injection and production wells from the reservoir half-zone controlled by the first electrode column module and the reservoir half-zone controlled by the second electrode column module, and then be recovered to the surface well site.

[0043] By changing the positive and negative poles of the non-uniform electric field, the first electrode post module displays a negative charge, and the second electrode post module displays a positive charge, as shown below. Figure 3 As shown, hydrogen gas is still in the polarized state before the electric field transformation.

[0044] In the reservoir half-region controlled by the first electrode column module, the electric field density is greater where the hydrogen molecules are negatively charged, and smaller where they are positively charged. Therefore, the electrostatic repulsion experienced by the negatively charged hydrogen molecules is greater than the electrostatic attraction experienced by the positively charged ones, resulting in a non-zero net force on the hydrogen molecules, directed towards the injection-production well. This causes the hydrogen to accelerate towards the injection-production well, increasing its flow velocity.

[0045] In the reservoir half-region controlled by the second electrode column module, the electric field density is greater where the hydrogen molecules are positively charged, and smaller where they are negatively charged. Therefore, the electrostatic repulsion experienced by the positively charged hydrogen molecules is greater than the electrostatic attraction experienced by the negatively charged ones. The net force on the hydrogen molecules is not zero, and the direction of the net force is towards the injection-production well. This results in an acceleration of the hydrogen towards the injection-production well, increasing the hydrogen flow velocity.

[0046] Therefore, in the short time (10) between the positive and negative poles of the non-uniform electric field, -12Within seconds, hydrogen in the reservoir half-zone controlled by the first electrode column module accelerates towards the injection-production well, and hydrogen in the reservoir half-zone controlled by the second electrode column module also accelerates towards the injection-production well. Under the action of a non-uniform electric field, the resultant force on the hydrogen causes it to generate an acceleration towards the injection-production well, propelling the hydrogen into the well and improving the hydrogen flow rate and recovery efficiency.

[0047] (3) During a long period of time (greater than 10) between the positive and negative poles of the non-uniform electric field. -12 (seconds) later, the hydrogen gas will be polarized again according to the current electric field distribution, generating positive charges along the direction of the electric field lines and negative charges along the opposite direction of the electric field lines, such as... Figure 4 As shown. At this point, the force state of the hydrogen is similar to that of the hydrogen during the injection process, and the hydrogen tends to flow towards the first electrode column module and the second electrode column module. During the hydrogen extraction process, in order to prevent the hydrogen from flowing towards the first electrode column module and the second electrode column module, it is necessary to change the positive and negative poles of the non-uniform electric field again to ensure that the hydrogen always flows towards the injection and production well with accelerated speed.

[0048] Therefore, hydrogen needs to be extracted at a rate of 10 12 The Hz converter shifts the positive and negative poles of the non-uniform electric field to prevent hydrogen flow from flowing towards the first and second electrode modules, thus maintaining the accelerated flow of hydrogen towards the injection and production wells. The shifting of the non-uniform electric field's positive and negative poles means changing the charge nature of the electrode columns from positive to negative, or vice versa.

[0049] This invention realizes electric field-enhanced underground hydrogen storage, which, when applied to underground hydrogen storage projects, helps to improve injection and extraction efficiency and increase hydrogen storage capacity.

[0050] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. An electric field-enhanced underground hydrogen storage system, characterized in that, Includes injection-production wells, a first electrode column module, and a second electrode column module; The injection-production well is used for the injection and production of hydrogen. The first electrode column module represents one type of electrode in the electric field, and the second electrode column module represents another opposite electrode in the electric field. The first electrode column module and the second electrode column module each carry equal amounts of opposite charges and are located on opposite sides at the same distance from the injection and production wells, forming a non-uniform electric field in the reservoir. The injection and production well extends from the surface well site deep into the reservoir, and is located in the middle of the entire electric field enhanced underground hydrogen storage system. The first electrode column module is located on one side of the injection-production well, and its height is equal to the reservoir thickness of the underground hydrogen storage structure. The second electrode column module is located on the other side of the injection-production well opposite to the first electrode column module, and its height is equal to the reservoir thickness of the underground hydrogen storage structure.

2. A method for electric field-enhanced underground hydrogen storage, characterized in that, The electric field enhanced underground hydrogen storage system as described in claim 1 is adopted; Hydrogen is injected into the reservoir of the underground hydrogen storage structure through injection-production wells. During the injection process, the hydrogen is polarized in the non-uniform electric field formed by the first electrode column module and the second electrode column module. The positive and negative charge centers of the hydrogen no longer coincide, generating induced dipoles. Hydrogen molecules form equal amounts of induced charges of opposite signs. The two induced charges are subjected to electrostatic attraction and electrostatic repulsion forces of different magnitudes and opposite directions by the non-uniform electric field, which causes the hydrogen to form a directional acceleration towards the first electrode column module or the second electrode column module. Hydrogen is extracted to the surface through injection and production wells. During the extraction process, the positive and negative poles of the non-uniform electric field are changed according to a set frequency, so that the hydrogen forms a directional acceleration towards the injection and production well. The transformation of the non-uniform electric field's positive and negative poles represents the positive and negative transformation of the charge properties of the first electrode post module and the second electrode post module.

3. The electric field-enhanced underground hydrogen storage method according to claim 2, characterized in that, During the injection process, hydrogen will enter the reservoir half-zone controlled by the first electrode column module and the reservoir half-zone controlled by the second electrode column module through the injection and production wells respectively. At this time, the first electrode column module displays a positive charge and the second electrode column module displays a negative charge. Hydrogen gas is polarized in the non-uniform electric field formed by the first electrode post module and the second electrode post module. The positive and negative charge centers of hydrogen gas no longer coincide, generating induced dipoles. Hydrogen molecules form equal amounts of induced charges of opposite signs, generating positive charges along the direction of the electric field lines and negative charges along the opposite direction of the electric field lines. In the reservoir half-region controlled by the first electrode post module, the electric field density is greater at the location of the negative charge of hydrogen molecules and smaller at the location of the positive charge. Therefore, the electrostatic attraction of the negative charge of hydrogen molecules is greater than the electrostatic repulsion of the positive charge. The net force on the hydrogen molecules is not zero, and the direction of the net force is towards the first electrode post module. As a result, the hydrogen gas accelerates towards the first electrode post module, and the flow velocity of the hydrogen gas increases. In the reservoir half-region controlled by the second electrode post module, the electric field density is greater at the location of the positive charge of hydrogen molecules and smaller at the location of the negative charge. Therefore, the electrostatic attraction of the positive charge of hydrogen molecules is greater than the electrostatic repulsion of the negative charge. The net force on the hydrogen molecules is not zero, and the direction of the net force is towards the second electrode post module. As a result, the hydrogen gas accelerates towards the second electrode post module, and the flow velocity of the hydrogen gas increases. Therefore, during the hydrogen injection process, the hydrogen in the reservoir half-region controlled by the first electrode column module will accelerate towards the first electrode column module, and the hydrogen in the reservoir half-region controlled by the second electrode column module will accelerate towards the second electrode column module.

4. The electric field-enhanced underground hydrogen storage method according to claim 3, characterized in that, During the hydrogen extraction process, hydrogen enters the injection and production wells from the reservoir half-zone controlled by the first electrode column module and the reservoir half-zone controlled by the second electrode column module, and is then recovered to the surface well site. The positive and negative poles of the non-uniform electric field are changed so that the first electrode post module displays a negative charge and the second electrode post module displays a positive charge. At this time, the hydrogen gas is still in the polarization state before the electric field change. In the reservoir half-region controlled by the first electrode column module, the electric field density is greater at the location of the negative charge of hydrogen molecules and smaller at the location of the positive charge. Therefore, the electrostatic repulsion force on the negative charge of hydrogen molecules is greater than the electrostatic attraction force on the positive charge. The net force on the hydrogen molecules is not zero, and the direction of the net force is towards the injection-production well. As a result, the hydrogen gas accelerates towards the injection-production well, and the flow velocity of the hydrogen gas increases. In the reservoir half-region controlled by the second electrode column module, the electric field density is greater at the location of the positive charge of hydrogen molecules and smaller at the location of the negative charge. Therefore, the electrostatic repulsion force on the positive charge of hydrogen molecules is greater than the electrostatic attraction force on the negative charge. The net force on the hydrogen molecules is not zero, and the direction of the net force is towards the injection-production well. As a result, the hydrogen gas accelerates towards the injection-production well, and the flow velocity of the hydrogen gas increases. Therefore, within a short period after the positive and negative poles of the non-uniform electric field are switched, hydrogen in the reservoir half-zone controlled by the first electrode column module will accelerate towards the injection-production well, and hydrogen in the reservoir half-zone controlled by the second electrode column module will also accelerate towards the injection-production well; the short period means no more than 10 seconds. -12 Second; After a long period of time during which the positive and negative poles of a non-uniform electric field are switched, the hydrogen gas will repolarize according to the current electric field distribution, generating positive charges along the direction of the electric field lines and negative charges along the opposite direction of the electric field lines; the long period of time is greater than 10. -12 Second; During hydrogen extraction, in order to prevent the hydrogen from flowing towards the first electrode column module and the second electrode column module, it is necessary to change the positive and negative poles of the non-uniform electric field again so that the hydrogen always flows towards the injection and production well at an accelerated speed.

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