Multi-dimensional cooperative control method for preventing hydrogen loss of salt cavern hydrogen storage

Abstract

The invention discloses a multi-dimensional cooperative control method for preventing hydrogen loss of a salt cavern hydrogen storage library, and the method comprises the steps: S1, executing salt cavern site selection and structure design operation, and obtaining an optimized salt cavern hydrogen storage library; step S2, performing cavity and shaft sealing operation on the salt cavern hydrogen storage library obtained in the step S1; s3, executing operation control operation on the salt cavern hydrogen storage library; and S4, after hydrogen is injected into the salt-cavern hydrogen storage library, monitoring and repairing operation of the salt-cavern hydrogen storage library is executed, and stable operation of the salt-cavern hydrogen storage library is guaranteed. According to the coupling effect of chemical, leakage, dissolution and adsorption multi-path hydrogen loss in the salt cavern hydrogen storage, combined inhibition of four hydrogen loss paths (chemical loss, leakage loss, dissolution loss and adsorption loss) can be achieved, and great practical significance is achieved.

Description

Technical Field

[0001] This invention relates to the field of underground hydrogen storage technology, and in particular to a multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage facilities. Background Technology

[0002] As the global energy system accelerates its transition towards low-carbon and sustainable energy, hydrogen energy, due to its cleanliness, high energy density, and renewable properties, will occupy an important position in the future energy structure. Salt cavern hydrogen storage facilities, leveraging the low permeability of salt rock (<10⁻⁶), [are crucial for sustainable development]. 18 m 2 The advantages of self-healing properties and huge storage capacity (the volume of a single salt cavern can reach 10) are significant. 5 ~10 6 m 3 Hydrogen storage has become the preferred solution for global strategic hydrogen energy storage.

[0003] Nine underground hydrogen storage facilities have been built globally, four of which are salt caverns, achieving a pure hydrogen storage ratio of 95%, thus verifying the feasibility of salt cavern hydrogen storage technology. However, due to its small molecular diameter (kinetic diameter 0.289 nm) and high chemical reactivity, hydrogen is easily lost in salt cavern environments through various pathways:

[0004] I. Chemical Loss: Minerals (such as gypsum and calcite) within the salt cavern undergo reduction reactions with hydrogen (e.g., SO42-). 2 -+4H2+H + →HS-+4H2O) generates impurity gases such as CO2 and H2S. At the same time, methanogenic bacteria in the salt cavern brine can convert H2 and CO2 into CH4 through hydrogenotrophic metabolism.

[0005] (4H2+CO2→CH4+2H2O), laboratory simulation results show that this type of loss can reach 3.2% of the hydrogen storage capacity per year;

[0006] II. Leakage Loss: Problems such as hydrogen embrittlement of the well casing, cracking of the cement sheath, and microfractures in the salt cavern interlayer can lead to hydrogen leakage, especially in high-permeability interlayers (permeability > 1×10⁻⁶). 17 m 2 Under these conditions, the annual leakage rate can reach 45%.

[0007] III. Losses via Dissolution and Adsorption: Research data from the Jintan T5-2 salt cavern shows that the solubility of hydrogen in brine reaches 0.0793 kg / m³. 3 During a single injection-production cycle, approximately 0.17% of the hydrogen is lost due to incomplete dissolution and precipitation. At the same time, the adsorption capacity of clay minerals (such as montmorillonite) in the salt cavern interlayer is as high as 1 mol / kg, which will cause adsorption loss. The cumulative adsorption loss during long-term storage accounts for 0.5% of the total hydrogen storage.

[0008] Currently, the combined effects of the aforementioned multiple hydrogen loss mechanisms, the limitations of existing technologies, and the inherent properties of hydrogen—high diffusivity and wide explosion limits—severely restrict the large-scale development of the hydrogen energy industry chain.

[0009] Therefore, developing a control method that can comprehensively consider multiple hydrogen loss mechanisms has become an urgent need for the practical application of salt cavern hydrogen storage technology. Summary of the Invention

[0010] The purpose of this invention is to address the technical deficiencies of existing technologies by providing a multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage facilities.

[0011] To this end, the present invention provides a multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage facilities, which includes the following steps:

[0012] Step S1: Perform salt cavern site selection and structural design operations to obtain an optimized salt cavern hydrogen storage tank;

[0013] Step S2: Perform cavity and wellbore sealing operations on the salt cavern hydrogen storage tank obtained in step S1;

[0014] Step S3: Perform operation control procedures on the salt cavern hydrogen storage tank;

[0015] Step S4: After injecting hydrogen into the salt cavern hydrogen storage tank, perform monitoring and repair operations on the salt cavern hydrogen storage tank to ensure its stable operation.

[0016] As can be seen from the technical solution provided by the present invention above, compared with the prior art, the present invention provides a multi-dimensional synergistic control method for preventing hydrogen loss in salt cavern hydrogen storage. Its design is scientific. The present invention targets the coupled effects of hydrogen loss through multiple pathways such as chemical, leakage, dissolution and adsorption in salt cavern hydrogen storage. It can systematically suppress the four major hydrogen loss pathways (chemical loss, leakage loss, dissolution loss and adsorption loss) from multiple dimensions such as site selection and structural design, materials and construction, operation and monitoring. The present invention is a salt cavern hydrogen storage control method that can significantly reduce hydrogen loss and has great practical significance.

[0017] After testing, this invention is a multi-dimensional collaborative prevention and control method for preventing hydrogen leakage and loss during salt cavern hydrogen storage. It belongs to the field of hydrogen energy emerging energy engineering construction and is applicable to large-scale underground long-term storage and peak-shaving scenarios of high-purity hydrogen, as well as improving the safety of hydrogen storage. Attached Figure Description

[0018] Figure 1 A basic flowchart of the multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage provided by the present invention.

[0019] Figure 2The overall flowchart of the multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage provided by the present invention.

[0020] Figure 3 A cross-sectional view of a specially designed salt cavern hydrogen storage wellbore with a multi-barrier composite structure designed to prevent hydrogen loss, based on the multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage facilities provided by this invention.

[0021] Figure 4 This is a schematic diagram of the structure of a salt cavern hydrogen storage reservoir for microbial inhibition and in-situ treatment, which is part of the multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage reservoirs provided by the present invention. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," 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 invention 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 invention.

[0024] In the description of this patent, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection or setting, a detachable connection or setting, or an integral connection or setting. Those skilled in the art can understand the specific meaning of the above terms in this patent according to the specific circumstances.

[0025] 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 as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0026] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0027] See Figures 1 to 4 This invention provides a multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage facilities, comprising the following steps:

[0028] Step S1: Perform salt cavern site selection and structural design operations to obtain an optimized salt cavern hydrogen storage tank;

[0029] In this invention, step S1 specifically includes the following steps:

[0030] Step S11: Select a salt rock layer that meets the preset conditions as the target salt rock layer;

[0031] It should be noted that the target salt rock layer is a salt rock layer in which a salt cave hydrogen storage reservoir is constructed.

[0032] In step S11, the preset conditions specifically include one or more of the following conditions:

[0033] First condition: The salt rock layer contains a clay interlayer with a thickness greater than the first preset value (e.g., thickness > 0.5m);

[0034] The second condition is that the purity of sodium chloride (NaCl) in the salt rock layer is greater than the first preset ratio (e.g., 95%), and the mass content of clay minerals is less than the second preset ratio (e.g., 5%).

[0035] The third condition is that the amount of hydrogen adsorbed by the clay interlayer in the salt rock layer is less than the second preset value (the second preset value can be 0.1 mol / kg or 0.3 mol / kg).

[0036] Fourth condition: The proportion of the microporous structure distribution area on the surface of the clay interlayer in the salt rock layer to the total surface area of ​​the clay interlayer is less than the third preset proportion (the third preset proportion is, for example, 78%); the purpose is to avoid clay interlayers with well-developed microporous structures (pore size < 30 nm).

[0037] The diameter of each pore in the microporous structure is less than 30 mm.

[0038] It should be noted that, for this invention, firstly, high-precision site selection is achieved using P-wave seismic exploration and 3D ground-penetrating radar to identify clay interlayers with a thickness >0.5m in the salt rock layer, and a three-dimensional map of the interlayer distribution is drawn. Then, core samples are taken from the target strata of the proposed reservoir, and the salt rock samples are analyzed by X-ray diffraction (XRD) and inductively coupled plasma mass spectrometry (ICP-MS), prioritizing pure salt rock (sodium chloride NaCl purity >95%) and samples containing Fe. 3+ SO42 -and CO3 2 Salt rock layers with strong oxidizing or alkaline components containing less than 5% clay minerals should be selected. Furthermore, areas rich in montmorillonite (adsorption capacity 1 mol / kg) should be avoided, and clay interlayers mainly composed of kaolinite (adsorption capacity of hydrogen 0.1 mol / kg) or illite (adsorption capacity of hydrogen 0.3 mol / kg) should be preferred.

[0039] In addition, the microstructure of clay interlayers was observed using scanning electron microscopy (SEM). Clay interlayers with well-developed micropores (pore size <30nm) were avoided (well-developed means that the proportion of micropores in the total surface area of ​​the clay interlayer is greater than 78%). Such structures can enhance hydrogen adsorption through capillary condensation. Experimental data showed that for every 10% decrease in the proportion of micropores, the adsorption amount decreased by 15%.

[0040] Step S12: Construct a salt cavern hydrogen storage tank that meets the preset requirements in the target salt rock layer;

[0041] In step S12, preset requirements are included, including at least one of the following:

[0042] The first requirement is that the salt cavern hydrogen storage tank must be a salt cavern with a salt rock layer purity > 95% (i.e., sodium chloride NaCl purity > 95%) and an inner wall integrity coefficient > 0.9.

[0043] The second requirement is that the target salt rock layer is a layered salt rock with a burial depth of 1000-2000 meters;

[0044] The third requirement is that the salt cavern hydrogen storage reservoir is a salt cavern structure consisting of a spherical upper part and a cylindrical lower part, and the ratio of the diameter to the height of the spherical shape is 1:3.

[0045] It should be noted that the bottom surface of the spherical crown is the top surface of the cylinder.

[0046] The fourth requirement is that the top of the salt cavern hydrogen storage facility should be reserved with pure salt rock with a thickness of 1.5 to 2 times the well diameter (the well diameter is the diameter of the well pipe / wellbore) to serve as a natural low-permeability barrier.

[0047] It should be noted that in the development and operation of salt caverns (which are typically used for energy storage, underground space utilization, and other scenarios, such as salt cavern gas storage and salt cavern oil storage), the well casing / wellbore is the core channel structure connecting the surface and underground salt cavern space, and its role runs through the entire life cycle of salt cavern construction, use, and maintenance.

[0048] It should be noted that, for this invention, after completing the above-mentioned high-precision site selection to avoid salt rock layers with high adsorption risk, priority is given to selecting salt caves with salt rock layer purity > 95% and salt cavern inner wall integrity coefficient > 0.9, and layered salt rock with a burial depth of 1000-2000 meters, to optimize the salt cavern structure in order to reduce the exposed area of ​​clay interlayers.

[0049] In addition, during the process of creating cavities in water-soluble salt rock (i.e., dissolving salt rock in salt rock layers with brine to form hollow salt caverns), the "nitrogen gas inhibition method" is used to control the shape of the cavity. By injecting nitrogen gas to isolate the interface between the brine and the salt rock, a salt cavern structure is formed, consisting of a spherical upper part with a diameter-to-height ratio of 1:3 and a cylindrical lower part. The cavity structure can avoid microcracks caused by stress concentration, thereby reducing new adsorption sites generated by the breakage of clay minerals under stress.

[0050] In addition, during the solution formation process, a layer of pure salt rock with a thickness of 1.5 to 2 times the well diameter should be reserved at the top of the salt cavern as a natural low-permeability barrier to prevent hydrogen from directly contacting the caprock. After the solution formation is completed, sonic logging technology is used to verify the integrity of the salt cavern's inner wall, requiring an inner wall integrity coefficient > 0.9.

[0051] Step S13: Construct a wellbore with a composite structure between the salt cavern and the surface to obtain an optimized salt cavern hydrogen storage reservoir;

[0052] Given that hydrogen leakage is one of the most serious pathways for hydrogen loss, primarily due to the tendency of hydrogen to undergo "hydrogen embrittlement" under high pressure, leading to hydrogen cracking, delamination, or fracture in metallic materials, especially high-strength steel, this invention requires the design of wellbore structures using high-hydrogen-embrittlement-resistant steel to prevent mechanical property degradation in the well casing structure.

[0053] In this invention, in step S13, the well casing includes a hollow cylindrical casing 1 made of stainless steel;

[0054] The inner wall of sleeve 1 is coated with a layer of nano-hydrogen barrier coating 2;

[0055] A ceramic material reinforcement layer 3 is provided on the outer wall of the sleeve 1;

[0056] The inner cavity of casing 1 is the central through hole 4 of the wellbore.

[0057] It should be noted that the ceramic material reinforcement layer 3 is a ceramic layer, and the main characteristics of the ceramic layer are high hardness, wear resistance, corrosion resistance and high temperature stability.

[0058] In practice, the sleeve is preferably made of 316L stainless steel.

[0059] In practice, the nano-hydrogen barrier coating is preferably a composite coating of nano-titanium dioxide (TiO2) and silicon dioxide (SiO2).

[0060] It should be noted that, for the present invention, as Figure 3As shown, the well casing composite structure, which combines 316L stainless steel, a nano-hydrogen barrier coating, and ceramic reinforcement, significantly improves resistance to hydrogen permeation and hydrogen embrittlement. For steels with high resistance to hydrogen permeation and embrittlement, austenitic stainless steel (such as 316L and 310S) can be selected as the main casing material, whose face-centered cubic structure effectively inhibits the aggregation and diffusion of hydrogen atoms in the crystal lattice.

[0061] The bushing has a three-layer structure. The middle layer is a 316L precision bushing. A very thin layer of polymer nanomaterials (such as a composite coating of nano-titanium dioxide (TiO2) and silicon dioxide (SiO2)) is sprayed onto the inner layer of the bushing, adhering tightly to the inner wall of the steel bushing, to prevent hydrogen atoms from diffusing into the metal interior. A high-modulus ceramic material reinforcement layer is placed on the outer layer of the bushing to resist the propagation of microcracks in the bushing.

[0062] Step S2: Perform cavity and wellbore sealing operations on the salt cavern hydrogen storage tank obtained in step S1;

[0063] In this invention, step S2 specifically includes the following steps:

[0064] Step S21: Perform micro-permeation interlayer identification and grouting sealing operations on the salt cavern hydrogen storage tank;

[0065] In this invention, step S21 specifically includes the following operations:

[0066] First, identify the micro-permeable interlayers in the salt rock interlayers of the salt cavern hydrogen storage reservoir;

[0067] Then, grouting and sealing treatment is performed on the surface of the micro-permeability interlayer to form a low-permeability sealing layer. The sealing layer can block the contact channel between hydrogen inside the salt cave and clay minerals in the salt rock layer outside the salt cave.

[0068] In practical implementation, the micro-permeability interlayer has a permeability > 1×10⁻⁶. 17 m 2 Salt rock interlayers.

[0069] It should be noted that naturally deposited salt rocks often contain highly permeable interlayers (composed of mudstone, siltstone, aquifers, or sulfate layers, etc.), which can become potential channels for hydrogen leakage.

[0070] In specific implementation of this invention, methods such as acoustic time difference, scanning technology, and local monitoring with H2 concentration sensors can be used to identify permeability > 1×10⁻⁶. 17 m 2 In the micro-permeable interlayer region, grouting can be performed on the surface of the interlayer to form a low-permeability barrier. At the same time, it further blocks the contact channel between hydrogen inside the salt cave and clay minerals in the salt rock layer outside the salt cave.

[0071] In practical implementation, grouting and sealing can be achieved using directional perforation technology (perforation angle ±15°). This involves injecting a low-viscosity, highly adhesive, delayed-setting, nano-sized composite grout of epoxy resin and nano-calcium carbonate (CaCO3) into the micro-permeability interlayer region (nanoparticle size 50nm, mass percentage of 10% in the grout), forming a permeability coefficient <1×10⁻⁶. 18 m 2 The sealing layer.

[0072] In practice, the composite grout can fill the pores of the interlayer and enhance the interfacial adhesion through nanoparticles. During the grouting process, segmented pressure control is adopted (initial pressure 5MPa, gradually increasing to 10MPa), and pressure changes and grout return are monitored in real time to prevent over-injection and rupture. This ensures that the grout diffuses in the interlayer to form a safe boundary with a radius equal to the interlayer thickness H, 50cm above and below (i.e., H±50cm), forming a stable and dense "leak-free isolation zone".

[0073] Step S22: Perform a multi-layer cement layer sealing operation with variable elastic modulus on the wellbore of the salt cavern hydrogen storage tank.

[0074] In this invention, see Figure 3 Step S22 specifically involves: covering the outside of the wellbore (specifically, the ceramic material reinforcement layer 3) of the salt cavern hydrogen storage reservoir with multiple layers of cement 5 (i.e., cement rings).

[0075] In practice, the cement layers consist of a high-modulus cement outer layer A, a variable-modulus flexible cement middle layer B, and a low-modulus cement inner layer C, distributed sequentially from the outside to the inside.

[0076] Among them, the elastic modulus E of the outer layer A of high modulus cement is ≥10 GPa;

[0077] The elastic modulus E of the intermediate layer B of the variable modulus flexible cement ranges from 3 to 6 GPa.

[0078] The elastic modulus E of the inner layer C of low modulus cement ranges from 1 to 2 GPa.

[0079] Furthermore, the low-modulus cement inner layer C is a low-modulus cement inner layer with high adhesion and strong bonding, specifically: a cement layer with added coupling agents (such as silanes).

[0080] It should be noted that, given the strong creep properties of salt rock, it will continuously deform and shrink towards the wellbore during long-term hydrogen injection and production, squeezing the casing and cementing cement. Traditional oil and gas well cement is prone to developing "micro-annulus," "interfacial debonding," or "radial cracks" after long-term pressure cycling, forming hydrogen leakage channels.

[0081] Therefore, in accordance with the changes in the stress field of the wellbore during sealing, the present invention designs the cement sealing layer as a partitioned composite structure, which consists of the following layers from the outside to the inside: an outer layer A of high modulus cement (E≥10GPa), a middle layer B of variable modulus flexible cement (E≈3~6GPa), and an inner layer C of low modulus cement (E≈1~2GPa) with high adhesion and strong bonding.

[0082] It should be noted that in the design of variable modulus cement material formulation, the high modulus outer layer A can be made of ordinary oil well cement + quartz powder or iron ore powder, and steel fiber reinforcement can be added to improve crack resistance and ensure that its mechanical strength can resist the deformation of external salt rock.

[0083] Expandable rubber particles can be added to the intermediate layer B of the variable modulus flexible cement to form a "ligament-like" microstructure with a large strain adaptability range, so as to absorb the deformation stress of the salt rock and effectively alleviate the deformation incoordination among the casing (the outer layer of the casing contains ceramic reinforcement material), cement and salt rock.

[0084] The cement inner layer C with high adhesion and strong bonding can be mixed with coupling agents (such as silanes) to improve the chemical bonding force with the surface of the casing (the outer layer of the casing contains ceramic reinforcement material) to adapt to the thermal expansion and hydrogen pressure transmitted by the casing (the outer layer of the casing contains ceramic reinforcement material), forming a "sealing strip" that prevents debonding and micro-cracks.

[0085] Step S23: Construct an isolation layer between hydrogen and brine in the salt cavern hydrogen storage tank;

[0086] In this invention, step S23 specifically involves: injecting an isolation liquid into the salt cavern to isolate the hydrogen gas inside the salt cavern from the brine that was used and left over during the dissolution and molding process of the salt cavern.

[0087] The isolation liquid is insoluble in the brine, and its density is less than that of the brine.

[0088] It should be noted that after the water-soluble cavity-forming stage in the salt rock layer is completed (i.e., the salt cavern is formed), an isolation liquid is injected into the hydrogen storage tank of the salt cavern through the injection-production pipe. The brine is displaced by the isolation liquid and discharged out through the brine discharge pipe. Then, hydrogen is injected into the hydrogen storage tank of the salt cavern through the injection-production pipe. The brine is displaced by the hydrogen and discharged through the brine discharge pipe. The isolation liquid is insoluble in brine and has a lower density than brine. During the subsequent hydrogen injection and production process, hydrogen and brine are always separated by the isolation liquid, blocking the direct contact interface between hydrogen and brine, which can significantly inhibit hydrogen dissolution.

[0089] Step S3: Perform operation control procedures on the salt cavern hydrogen storage tank;

[0090] It should be noted that in salt cavern hydrogen storage facilities, hydrogen undergoes reduction reactions with high-valence metal oxides, carbonates, sulfates, etc. in the interlayers or salt rocks, or microorganisms in the brine (such as methanogens and sulfate-reducing bacteria) consume hydrogen to generate byproducts such as CH4, CO2, and H2S, which can lead to an annual hydrogen consumption rate as high as 3.2% and reduce the purity of hydrogen. At the same time, these acidic byproducts can exacerbate the corrosion of the well casing and cement sheath, indirectly inducing structural damage and leakage.

[0091] Meanwhile, hydrogen inevitably comes into contact with residual brine (high-concentration NaCl solution) during salt cavern storage, resulting in physical dissolution. Studies have shown that the maximum hydrogen dissolution loss in residual brine is approximately 0.17% of the total hydrogen storage, leading to a decrease in hydrogen storage efficiency. Although the hydrogen dissolution and biochemical reactions in the brine result in a relatively low loss value, this loss is continuous and irreversible during long-term salt cavern hydrogen storage. Furthermore, the hydrogen dissolved in the brine may also promote microbial growth.

[0092] In this invention, step S3 specifically includes the following steps:

[0093] Step S31, perform microbial risk identification: before the first injection of hydrogen into the salt cavern hydrogen storage tank, monitor and identify microorganisms in the salt cavern hydrogen storage tank that can consume hydrogen;

[0094] In practice, a microbial monitoring chip is installed at the bottom of the salt cavern hydrogen storage tank to monitor and identify microorganisms in the tank that can consume hydrogen.

[0095] It should be noted that, in this invention, after the salt cavern creation stage is completed and before the first hydrogen injection, a brine sample is collected from the bottom of the salt cavern for microbial community species detection and microbial community structure genome sequencing, as well as for the Fe required for microbial growth. 3- , low SO4 2 -and low CO3 2 - Nutrient concentration detection. Based on the detected hydrogen-consuming bacteria such as methanogens, sulfate-reducing bacteria, and iron-reducing bacteria, corresponding antimicrobial agents (i.e., microbial inhibitors) such as sodium nitrate (NaNO3), quaternary ammonium salts (such as DDAC), and chlorine dioxide (ClO2) were prepared according to their types and ratios.

[0096] It should be noted that, in this invention, the microbial inhibitors include sodium nitrate (NaNO3), quaternary ammonium salts (such as DDAC), or chlorine dioxide (ClO2).

[0097] like Figure 4The diagram shows an in-situ treatment for microbial inhibition. A downhole parameter sensing module is installed at the bottom of the salt cavern hydrogen storage tank, including an in-situ spectral gas analyzer, a DNA / RNA in-situ microbial monitoring chip, gas sensors (CH4, CO2, H2S, N2), and sensors for temperature, pH, and redox potential Eh. At the same time, a storage and injection device for microbial inhibitors is installed at the top of the wellbore.

[0098] Step S32: Perform Eh-pH redox environment regulation to inhibit the reaction between minerals, microorganisms and hydrogen.

[0099] Step S32 specifically involves: controlling the cavity environment of the salt cavern hydrogen storage reservoir to a state of low pH and high redox potential Eh, thereby inhibiting the reaction rate between microorganisms and hydrogen.

[0100] Low pH refers to a pH range of 8 to 9;

[0101] A high redox potential Eh refers to a redox potential Eh > +200mV.

[0102] In step S32, specifically, by injecting Eh-pH environment control solution into the salt cavern hydrogen storage tank, the cavity environment of the salt cavern hydrogen storage tank is controlled to a state of low pH and high redox potential Eh.

[0103] The Eh-pH environmental control solution includes chemical oxidants (such as low-concentration liquid H2O2), nitrate solutions, or carbonate solutions.

[0104] It should be noted that the above three Eh-pH environment control solutions are:

[0105] 1. Oxidizing agent solutions (such as NO3) - In solutions and low-concentration liquid H2O2, it significantly increases Eh (redox potential) and inhibits reducing reactions and anaerobic microorganisms. It has a very weak effect on pH, only potentially causing slight acidification at higher concentrations.

[0106] 2. Carbonate solutions (Na2CO3) significantly increase the pH (forming an alkaline buffer solution, maintaining a pH of ≈8–9 or higher), have minimal impact on Eh, and essentially do not alter the redox environment.

[0107] It should be noted that, given that various hydrogen-minerals or microorganisms are highly reactive under acidic (pH<7) or low redox potential (Eh) conditions, this invention can regulate the cavity environment of the hydrogen storage cavern to a low pH (pH≈8~9) and high redox potential (Eh>+200mV) state by quantitatively injecting low concentrations of chemical oxidants (such as low concentrations of liquid H2O2), nitrate solutions, or carbonate solutions into the hydrogen storage cavern, thereby inhibiting the reaction rate between reducing mineral components, microorganisms, and hydrogen.

[0108] It should be noted that, in this invention, the mass concentration of low-concentration liquid H2O2 is 0.5-10 mg·L. -1 Low concentration of NO3 - The mass concentration of the (nitrate) solution is 50–500 mg·L⁻¹. -1 Low concentration of CO3 2- The mass concentration of the (carbonate) solution is 50–500 mg·L⁻¹. -1 ;

[0109] Step S4: After injecting hydrogen into the salt cavern hydrogen storage tank, perform monitoring and repair operations on the salt cavern hydrogen storage tank to ensure its stable operation.

[0110] Step S4 specifically includes the following operations:

[0111] Step S41: The concentration of various types of gases (such as CH4, H2S or CO2) in the salt cavern hydrogen storage tank is detected by a gas sensor, and the redox potential (Eh) and pH value in the salt cavern hydrogen storage tank are detected by a pH and redox potential (Eh) sensor.

[0112] Step S42: When the absolute concentration of a certain gas exceeds its preset safety threshold (CH4≥50ppm, H2S≥5ppm, CO2≥500ppm), it is determined that the gas concentration has changed abnormally. Microbial inhibitors are injected into the salt cavern hydrogen storage tank to control the reaction between microorganisms and hydrogen (e.g., reaction rate). When the detected redox potential (Eh) and pH values ​​meet the preset conditions, it is determined that the redox potential (Eh) and pH values ​​have changed abnormally. The corresponding Eh-pH environmental control solution is injected into the salt cavern hydrogen storage tank to adjust and control the redox potential (Eh) and pH values ​​of the cavity environment of the salt cavern hydrogen storage tank. Specifically, the cavity environment of the salt cavern hydrogen storage tank is controlled at a low pH (pH 8-9) and a high redox potential (Eh>+200mV).

[0113] Pre-set conditions include pH ≤ 7.5 or pH ≥ 9.5, and Eh ≤ +150mV;

[0114] If pH ≤ 7.5 or pH ≥ 9.5, it is determined that the pH detection value has changed abnormally. At this time, a chemical oxidant (such as low-concentration liquid H2O2) or nitrate solution is injected into the salt cavern hydrogen storage tank.

[0115] If Eh ≤ +150mV, it is determined that the redox potential Eh detection value has changed abnormally, and at this time, carbonate solution is injected into the salt cavern hydrogen storage tank.

[0116] In specific implementation, in step S42, the microbial inhibitors include sodium nitrate solution (NaNO3), quaternary ammonium salts (such as DDAC), or chlorine dioxide (ClO2);

[0117] Eh-pH environment control solutions include chemical oxidants (such as low-concentration liquid H2O2), nitrate solutions, or carbonate solutions.

[0118] In step S4, for specific implementation details, see [link to relevant documentation]. Figure 4 As shown, the salt cavern hydrogen storage tank is equipped with an inhibitor and control fluid injection pipe, as well as a hydrogen combined injection and production tubing.

[0119] The top opening of the well shaft is sealed with a sealing cover.

[0120] The upper part of the inhibitor and control fluid injection pipe and the hydrogen composite injection and production string vertically penetrates the wellbore center through hole 4 and the sealing cover plate at the top of the wellbore.

[0121] The upper end of the inhibitor and control fluid injection tube is connected to an Eh-pH environmental control fluid (e.g., sodium carbonate solution) injection device located on the ground via a first connecting pipe equipped with a one-way check valve.

[0122] The Eh-pH environmental control liquid injection device is used to inject the Eh-pH environmental control liquid into the salt cavern hydrogen storage tank.

[0123] It should be noted that the sodium carbonate solution used as an Eh-pH environment control solution is typically water (H2O) as the solvent, with a concentration range of 0.05 g·L⁻¹. -1 -0.5g·L -1 This is done to maintain the pH of the liquid phase in the cavity within the range of 8-9, thereby inhibiting the activity of sulfate-reducing bacteria and other anaerobic microorganisms, and reducing the side reaction rate of hydrogen with minerals / acidic media.

[0124] In this invention, the sodium carbonate solution is used to establish and stabilize the liquid-phase buffer system, and to control the pH at 8-9, with a mass concentration of 0.05 g·L⁻¹. -1 -0.5g·L -1Consistent with the previous statement, this concentration can significantly inhibit the activity of anaerobic bacteria such as sulfate-reducing bacteria (SRB) and methanogens.

[0125] In practice, the upper end of the inhibitor and regulating fluid injection pipe is also connected to the microbial inhibitor on-demand quantitative injection system (i.e., mineral / microbial inhibitor storage and injection device) located on the ground via a second connecting pipe equipped with a one-way check valve.

[0126] The microbial inhibitor on-demand quantitative injection system is used to inject microbial inhibitor solutions into the salt cavern hydrogen storage reservoir.

[0127] It should be noted that the upper end of the inhibitor and control fluid injection tube is connected to one end of the first connecting pipe and one end of the second connecting pipe via a three-way valve.

[0128] The hydrogen injection and production string is connected to the existing hydrogen injection equipment located on the ground via a third connecting pipe equipped with a switch valve.

[0129] It should be noted that, in the present invention, during the operation of the salt cavern hydrogen storage facility, the changes in gas composition, oxidation-reduction potential (Eh), pH, temperature and other environmental parameters, as well as the fluctuations in hydrogen pressure at the micro-permeable interlayers in the salt rock interlayers of the salt cavern are monitored by a parameter sensing module installed downhole.

[0130] If abnormal changes in the concentration of gases such as CH4, H2S, or CO2 are detected by the gas sensor in the salt cavern, the microbial inhibitor on-demand quantitative injection system (i.e., mineral / microbial inhibitor storage and injection device) is activated to inhibit the activity of hydrogen-consuming bacteria such as methanogens and sulfate-reducing bacteria.

[0131] In this invention, for specific implementation, see [link to relevant documentation]. Figure 4 As shown, the microbial inhibitor on-demand quantitative injection system (i.e., mineral / microbial inhibitor storage and injection device) includes a microbial inhibitor storage tank, a first metering pump, and a PLC controller;

[0132] Microbial inhibitor storage tank, used to store microbial inhibitors;

[0133] The inlet of the first metering pump is located below the liquid level inside the microbial inhibitor storage tank, and is used to transport the microbial inhibitor solution to the salt cavern hydrogen storage tank.

[0134] The PLC controller is communicatively connected to the detection output of the downhole parameter sensing module (specifically a gas sensor) installed at the bottom of the salt cavern hydrogen storage tank and the control terminal of the first metering pump. It receives real-time concentration detection values ​​of various preset gases from the downhole parameter sensing module (specifically the gas sensor). When the concentration of a certain gas exceeds its preset safety threshold (CH4 ≥ 50 ppm, H2S ≥ 5 ppm, CO2 ≥ 500 ppm), it determines that the gas concentration has changed abnormally and sends a control signal to the first metering pump to activate it and inject microbial inhibitors into the salt cavern hydrogen storage tank to control the reaction between microorganisms and hydrogen. These microbial inhibitors include sodium nitrate (NaNO3), quaternary ammonium salts (such as DDAC), or chlorine dioxide (ClO2).

[0135] Among them, the downhole parameter sensing module (specifically, gas sensors for CH4, CO2, H2S, and N2) is used to preset the concentrations of various types of gases (such as CH4, H2S, or CO2) in the salt cavern hydrogen storage tank.

[0136] It should be noted that the microbial inhibitor on-demand quantitative injection system (i.e., mineral / microbial inhibitor storage and injection device) includes a vertical microbial inhibitor storage tank equipped with a level gauge. The bottom of the storage tank has a preparation tank equipped with a stirrer and an automatic water inlet, which can dilute solid agents (such as H2O2, sodium carbonate, sodium nitrate) or high-concentration solutions to the required concentration, ensuring uniform and stable microbial inhibitor distribution. A metering pump achieves quantitative delivery of the microbial inhibitor solution. The metering pump outlet is equipped with a one-way valve and a check valve to prevent backflow. The remaining amount of microbial inhibitor in the storage tank is monitored by the level gauge. The microbial inhibitor enters the wellbore of the salt cavern hydrogen storage tank through the injection interface at the wellhead, ultimately reaching the liquid phase or gas-liquid interface of the salt cavern hydrogen storage tank cavity. Then, the downhole sensor module provides real-time feedback on changes in Eh, pH, and gas composition within the cavity. If abnormal gas composition is detected, the PLC controller automatically adjusts the pumping rate and injection concentration of the inhibitor accordingly.

[0137] In this invention, specifically, the Eh-pH environmental control liquid injection device includes an Eh-pH environmental control liquid storage tank, a second metering pump, and a PLC controller.

[0138] Eh-pH environmental control solution storage tank, used to store Eh-pH environmental control solution;

[0139] The inlet of the second metering pump is located below the liquid level in the Eh-pH environmental control liquid storage tank, and is used to transport the Eh-pH environmental control liquid to the salt cavern hydrogen storage tank.

[0140] The PLC controller is connected to the detection output of the downhole parameter sensing module (specifically, the pH and redox potential Eh sensors) installed at the bottom of the salt cavern hydrogen storage tank and the control terminal of the second metering pump. It is used to receive the redox potential (Eh) and pH detection values ​​in the salt cavern hydrogen storage tank in real time from the downhole parameter sensing module (specifically, the pH and redox potential Eh sensors). When the preset conditions are met, it is determined that the redox potential (Eh) and pH detection values ​​have changed abnormally, and a control signal is sent to the second metering pump to control the second metering pump to start and inject the corresponding Eh-pH environmental control liquid into the salt cavern hydrogen storage tank to adjust and control the redox potential Eh and pH values ​​of the cavity environment of the salt cavern hydrogen storage tank. Specifically, the cavity environment of the salt cavern hydrogen storage tank is controlled to be in a low pH (pH 8-9) and high redox potential Eh (Eh>+200mV) state.

[0141] Pre-set conditions include pH ≤ 7.5 or pH ≥ 9.5, and Eh ≤ +150mV;

[0142] If pH ≤ 7.5 or pH ≥ 9.5, it is determined that the pH detection value has changed abnormally. At this time, a chemical oxidant (such as low-concentration liquid H2O2) or nitrate solution is injected into the salt cavern hydrogen storage tank.

[0143] If Eh ≤ +150mV, it is determined that the redox potential Eh detection value has changed abnormally, and at this time, carbonate solution is injected into the salt cavern hydrogen storage tank.

[0144] It should be noted that in this invention, oxidizing agent solutions (such as NO3) - Solutions containing low concentrations of H₂O₂ (liquid phase) primarily and significantly increase the redox potential (Eh), inhibiting reducing reactions and anaerobic microorganisms. The effect on pH is very weak, only potentially causing slight acidification at higher concentrations. Carbonate solutions (Na₂CO₃) significantly increase the pH (forming an alkaline buffer solution, maintaining a pH ≈ 8–9 or higher), with minimal effect on Eh, essentially not altering the redox environment.

[0145] Among them, the pH and redox potential Eh sensors can detect the pH and redox potential Eh inside the salt cavern hydrogen storage tank in real time.

[0146] Controlling the reaction between microorganisms and hydrogen. Microbial inhibitors include sodium nitrate (NaNO3), quaternary ammonium salts (such as DDAC), or chlorine dioxide (ClO2).

[0147] It should be noted that the microbial inhibitor on-demand quantitative injection system and the Eh-pH environmental control solution injection device can share a single PLC controller.

[0148] It should be noted that the Eh-pH environmental control fluid injection device includes a vertical Eh-pH environmental control fluid storage tank equipped with a level gauge. The bottom of the storage tank has a preparation tank equipped with a stirrer and an automatic water inlet, which can dilute solid reagents (such as DDAC, ClO2, sodium nitrate) or high-concentration solutions to the required concentration, ensuring the uniformity and stability of the Eh-pH environmental control fluid. Quantitative delivery is achieved through a second metering pump, the outlet of which is equipped with a one-way valve and a check valve to prevent backflow. The remaining amount of Eh-pH environmental control fluid in the storage tank is monitored by the level gauge. The Eh-pH environmental control fluid enters the wellbore of the salt cavern hydrogen storage tank through the injection interface at the wellhead, ultimately reaching the liquid phase or gas-liquid interface within the salt cavern hydrogen storage tank cavity. Downhole sensor modules provide real-time feedback on pH and Eh values ​​within the cavity. If abnormal Eh or pH values ​​are detected, the PLC controller automatically adjusts the pumping rate and injection concentration of the Eh-pH environmental control fluid accordingly.

[0149] It should be noted that, in this invention, soluble oxidizing ions, such as nitrates (NO3), are quantitatively injected into the liquid phase of the salt cavern hydrogen storage reservoir. - This increases the redox potential and inhibits the growth of sulfate-reducing bacteria and methanogens through microbial community competition. To adjust the pH, a carbonate buffer (e.g., Na₂CO₃ solution) is injected into the chamber to maintain the pH of the chamber liquid phase at approximately 8–9.

[0150] It should be noted that, for this invention, the Eh-pH control scheme is adjusted based on abnormal changes in the redox potential (Eh) and pH parameters in the cavity environment of the salt cavern hydrogen storage tank (such as increasing / decreasing the injection amount of NO3- and low-concentration liquid H2O2).

[0151] It should be noted that, for the present invention, in response to the abnormal pressure phenomenon in the micro-permeable interlayer of the salt rock interlayer in the salt cavern, a polymer gel (such as polyacrylamide or silicate gel) that can permeate micro-fractures and fill micro-voids is injected again to repair the micro-permeable interlayer, forming a composite sealing strip. The H2 concentration is re-checked by the sensor to see if it has returned to normal, and the integrity of the cementing interface is detected by acoustic wave, so as to realize the whole process response of "leakage → early warning → repair".

[0152] To better understand the present invention, the working principle of the present invention will be explained below.

[0153] This invention can suppress the four major hydrogen loss pathways (chemical loss, leakage loss, dissolution loss, and adsorption loss), as detailed below:

[0154] I. Suppression of hydrogen chemical loss.

[0155] In this invention, chemical loss is suppressed through mineral selection and chemical environment control. Low-Fe minerals are preferred during the design phase. 3 +, low SO4 2 - Low CO3 2 - Salt rock layers with a content (mass content < 5%) are used to avoid reduction reactions between hydrogen and oxidizing components; during the operation phase, a small amount of oxidant (such as H2O2, NO3) is injected into the cavity at the initial stage of hydrogen injection. - A solution is used to maintain the redox potential of the chamber within a positive range, thereby inhibiting the metabolic consumption of hydrogen by anaerobic bacteria. Simultaneously, a microbial inhibitor storage and injection system is configured to quantitatively inject substances such as quaternary ammonium salts (e.g., DDAC), chlorine dioxide (ClO2), and sodium nitrate (NaNO3) (i.e., periodically injecting microbial inhibitors) to achieve long-term microbial control and reduce the chemical consumption of hydrogen from the source.

[0156] II. Suppression of hydrogen leakage and loss.

[0157] This invention proposes a multi-barrier structure design to address the problems of micro-fracture leakage and sealing failure in wellbore. First, the wellbore utilizes a composite casing of 316L stainless steel, a nano-hydrogen-barrier coating, and ceramic reinforcement, significantly improving resistance to hydrogen embrittlement and permeability. Second, a multi-layered cement seal with variable elastic modulus is implemented on the outer side of the casing, where the inner cement layer is flexible and crack-resistant, the middle cement layer has high modulus and creep resistance, and the outer cement layer has high adhesion and steel affinity, ensuring long-term sealing stability. Third, for the micro-permeable interlayers and channels within the salt rock interlayers of the salt cavern hydrogen storage facility, nano-slurry directional grouting is used for sealing, further eliminating potential leakage paths. Fourth, real-time monitoring of the wellbore is achieved through fiber optic sensors, enabling rapid in-situ repair in case of abnormal leakage, effectively reducing the risk of leakage losses.

[0158] III. Suppression of hydrogen dissolution loss.

[0159] In this invention, to address the problem of hydrogen dissolution in brine, before injecting hydrogen, an isolation liquid that is insoluble in brine and has a lower density than brine is injected into the salt cavern hydrogen storage tank through the injection-production pipe. This reduces direct contact between hydrogen and brine, and the hydrogen and brine are always separated by the isolation liquid, blocking the direct contact interface between hydrogen and brine, fundamentally reducing the dissolution rate and significantly inhibiting hydrogen dissolution.

[0160] IV. Suppression of hydrogen adsorption loss.

[0161] In this invention, to address the physical and chemical adsorption of hydrogen by salt rock interlayers and pores, a combination of interlayer control and surface passivation measures is adopted. First, during the design and cavitation of the salt cavern, areas rich in clay or porous interlayers are avoided as much as possible. Second, for unavoidable exposed interlayer surfaces, nano-silica sol or polymer materials are used for surface passivation coating to seal active sites and reduce hydrogen adsorption. Third, during the operation of the salt cavern hydrogen storage tank, a high-pressure constant-pressure control strategy is adopted to avoid the salt cavern hydrogen storage tank being in a low-pressure range for extended periods (adsorption is more significant at low pressure), and inert gases (such as nitrogen) are periodically injected to flush and desorb from the interlayer areas, preventing hydrogen retention and accumulation. Through the combination of structural design and operational optimization, long-term suppression of adsorption loss is effectively achieved.

[0162] In summary, compared with existing technologies, the multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage tanks provided by this invention has the following technical advantages:

[0163] 1. This invention adopts a wellbore composite structure of 316L stainless steel + nano hydrogen barrier coating + ceramic reinforcement, which can significantly improve the resistance to hydrogen permeation and hydrogen embrittlement. At the same time, a layered elastic cement sealing system is introduced, which, combined with the deformation characteristics of salt rock, improves the integrity of the sealing.

[0164] 2. In this invention, an isolation liquid that is insoluble in brine and has a lower density than brine is injected at the interface between brine and hydrogen, so that hydrogen and brine are always separated by the isolation liquid, preventing direct contact between hydrogen and brine.

[0165] 3. This invention employs in-situ identification of hydrogen-consuming microorganisms and injection of antibacterial agents to inhibit the activity of hydrogen-consuming microbial communities. Simultaneously, a trace amount of H2O2 and sodium carbonate buffer solution are injected to regulate the redox potential and acid-base environment of the cavity, thereby inhibiting the reduction reaction between hydrogen and microorganisms / minerals.

[0166] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage facilities, characterized in that, Includes the following steps: Step S1: Perform salt cavern site selection and structural design operations to obtain an optimized salt cavern hydrogen storage tank; Step S2: Perform cavity and wellbore sealing operations on the salt cavern hydrogen storage tank obtained in step S1; Step S3: Perform operation control procedures on the salt cavern hydrogen storage tank; Step S4: After injecting hydrogen into the salt cavern hydrogen storage tank, perform monitoring and repair operations on the salt cavern hydrogen storage tank to ensure its stable operation.

2. The multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage tanks as described in claim 1, characterized in that, Step S1 specifically includes the following steps: Step S11: Select a salt rock layer that meets the preset conditions as the target salt rock layer; Step S12: Construct a salt cavern hydrogen storage tank that meets the preset requirements in the target salt rock layer; Step S13: Construct a wellbore with a composite structure between the salt cavern and the surface to obtain an optimized salt cavern hydrogen storage reservoir.

3. The multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage tanks as described in claim 2, characterized in that, In step S11, the preset conditions specifically include one or more of the following conditions: First condition: The salt rock layer contains a clay interlayer with a thickness greater than the first preset value; Second condition: The purity of sodium chloride (NaCl) in the salt rock layer is greater than the first preset ratio, and the mass content of clay minerals is less than the second preset ratio; Third condition: The amount of hydrogen adsorbed by the clay interlayer in the salt rock layer is less than the second preset value; Fourth condition: The proportion of the microporous structure distribution area on the surface of the clay interlayer in the salt rock layer to the total surface area of ​​the clay interlayer is less than the third preset proportion; The diameter of each pore in the microporous structure is less than 30 mm; And / or, In step S12, preset requirements are included, including at least one of the following: The first requirement is that the salt cavern hydrogen storage reservoir must be a salt cavern with a salt rock layer purity > 95% and an inner wall integrity coefficient > 0.

9. The second requirement is that the target salt rock layer is a layered salt rock with a burial depth of 1000-2000 meters; The third requirement is that the salt cavern hydrogen storage reservoir is a salt cavern structure consisting of a spherical upper part and a cylindrical lower part, and the ratio of the diameter to the height of the spherical shape is 1:

3. Fourth requirement: The top of the salt cavern hydrogen storage facility should be reserved with pure salt rock with a thickness of 1.5 to 2 times the well diameter; And / or, In step S13, the well casing includes a hollow cylindrical casing (1) made of stainless steel; The inner wall of the sleeve (1) is coated with a layer of nano hydrogen barrier coating (2); The outer wall of the sleeve (1) is covered with a ceramic material reinforcement layer (3); The inner cavity of the casing (1) is the central through hole (4) of the wellbore.

4. The multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage tanks as described in claim 1, characterized in that, Step S2 specifically includes the following steps: Step S21: Perform micro-permeation interlayer identification and grouting sealing operations on the salt cavern hydrogen storage tank; Step S22: Perform a multi-layer cement layer sealing operation with variable elastic modulus on the wellbore of the salt cavern hydrogen storage tank. Step S23: Construct an isolation layer between hydrogen and brine in the salt cavern hydrogen storage tank.

5. The multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage tanks as described in claim 4, characterized in that, Step S21 specifically includes the following operations: First, identify the micro-permeable interlayers in the salt rock interlayers of the salt cavern hydrogen storage reservoir; Then, grouting and sealing treatment is performed on the surface of the micro-permeability interlayer to form a low-permeability sealing layer. The sealing layer can block the contact channel between hydrogen inside the salt cave and clay minerals in the salt rock layer outside the salt cave. And / or, Step S22 specifically involves: covering the outside of the wellbore of the salt cavern hydrogen storage tank with multiple layers of cement (5); The multi-layer cement structure includes, from the outside to the inside, a high-modulus cement outer layer A, a variable-modulus flexible cement middle layer B, and a low-modulus cement inner layer C. Among them, the elastic modulus E of the outer layer A of high modulus cement is ≥10 GPa; The elastic modulus E of the intermediate layer B of the variable modulus flexible cement ranges from 3 to 6 GPa. The elastic modulus E of the inner layer C of low modulus cement ranges from 1 to 2 GPa. And / or, Step S23 specifically involves injecting an isolation liquid into the salt cavern to isolate the hydrogen gas inside the salt cavern from the brine that was used and left over during the dissolution and molding process. The isolation liquid is insoluble in the brine, and its density is less than that of the brine.

6. The multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage tanks as described in claim 1, characterized in that, Step S3 specifically includes the following steps: Step S31, perform microbial risk identification: before the first injection of hydrogen into the salt cavern hydrogen storage tank, monitor and identify microorganisms in the salt cavern hydrogen storage tank that can consume hydrogen; Step S32: Perform Eh-pH redox environment regulation to inhibit the reaction between minerals, microorganisms and hydrogen.

7. The multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage tanks as described in claim 6, characterized in that, In step S32, by injecting Eh-pH environment control solution into the salt cavern hydrogen storage tank, the cavity environment of the salt cavern hydrogen storage tank is controlled at a low pH and high redox potential Eh, thereby inhibiting the reaction rate between microorganisms and hydrogen. Among them, the Eh-pH environmental control solution includes chemical oxidants, nitrate solutions, or carbonate solutions; Low pH refers to a pH range of 8 to 9; A high redox potential Eh refers to a redox potential Eh > +200mV.

8. The multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage tanks as described in claim 1, characterized in that, Step S4 specifically includes the following operations: Step S41: The concentrations of various types of gases in the salt cavern hydrogen storage tank are detected by a gas sensor, and the redox potential Eh and pH values ​​in the salt cavern hydrogen storage tank are detected by a pH and redox potential Eh sensor. Step S42: When the absolute concentration of a certain gas exceeds its preset safety threshold, it is determined that the gas concentration has changed abnormally. Microbial inhibitors are injected into the salt cavern hydrogen storage tank to control the reaction between microorganisms and hydrogen. When the detected redox potential Eh and pH values ​​meet the preset conditions, it is determined that the redox potential Eh and pH values ​​have changed abnormally. The corresponding Eh-pH environmental control liquid is injected into the salt cavern hydrogen storage tank to adjust and control the redox potential Eh and pH values ​​of the cavity environment of the salt cavern hydrogen storage tank. Pre-set conditions include pH ≤ 7.5 or pH ≥ 9.5, and Eh ≤ +150mV; If pH ≤ 7.5 or pH ≥ 9.5, the pH value is considered to have changed abnormally. If Eh ≤ +150mV, then the redox potential Eh detection value is considered to have changed abnormally.

9. The multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage tanks as described in any one of claims 1 to 8, characterized in that, The salt cavern hydrogen storage facility is equipped with inhibitor and control fluid injection pipes, as well as a hydrogen combined injection and production string. The upper end of the inhibitor and control fluid injection tube is connected to the Eh-pH environmental control fluid injection device located on the ground via a first connecting pipe equipped with a one-way check valve. The Eh-pH environmental control liquid injection device is used to inject the Eh-pH environmental control liquid into the salt cavern hydrogen storage tank. The upper end of the inhibitor and regulating fluid injection tube is also connected to the microbial inhibitor on-demand quantitative injection system located on the ground via a second connecting pipe equipped with a one-way check valve. The microbial inhibitor on-demand quantitative injection system is used to inject microbial inhibitor solutions into the salt cavern hydrogen storage reservoir.

10. The multi-dimensional collaborative control method for preventing hydrogen loss in salt cavern hydrogen storage as described in claim 9, characterized in that, A microbial inhibitor on-demand quantitative injection system includes a microbial inhibitor storage tank, a first metering pump, and a PLC controller; Microbial inhibitor storage tank, used to store microbial inhibitors; The inlet of the first metering pump is located below the liquid level inside the microbial inhibitor storage tank, and is used to transport the microbial inhibitor solution to the salt cavern hydrogen storage tank. The PLC controller is connected to the detection output of the gas sensor in the downhole parameter sensing module installed at the bottom of the salt cavern hydrogen storage tank and the control terminal of the first metering pump. It is used to receive the preset concentration detection values ​​of multiple gases sent by the downhole gas sensor in real time. When the concentration of a certain gas exceeds its preset safety threshold, it is determined that the gas concentration has changed abnormally, and a control signal is sent to the first metering pump to control the start of the first metering pump to inject microbial inhibitors into the salt cavern hydrogen storage tank to control the reaction between microorganisms and hydrogen. And / or, Eh-pH environmental control solution injection device, including Eh-pH environmental control solution storage tank, second metering pump and PLC controller; Eh-pH environmental control solution storage tank, used to store Eh-pH environmental control solution; The inlet of the second metering pump is located below the liquid level in the Eh-pH environmental control liquid storage tank, and is used to transport the Eh-pH environmental control liquid to the salt cavern hydrogen storage tank. The PLC controller is connected to the detection output terminals of the pH and redox potential (Eh) sensors in the downhole parameter sensing module installed at the bottom of the salt cavern hydrogen storage tank, as well as the control terminal of the second metering pump. It is used to receive the redox potential (Eh) and pH detection values ​​in the salt cavern hydrogen storage tank in real time from the sensors. When the preset conditions are met, it determines that the redox potential (Eh) and pH detection values ​​have changed abnormally, sends a control signal to the second metering pump, and controls the second metering pump to start, injecting the corresponding Eh-pH environmental control liquid into the salt cavern hydrogen storage tank to adjust and control the redox potential (Eh) and pH values ​​of the cavity environment of the salt cavern hydrogen storage tank. Pre-set conditions include pH ≤ 7.5 or pH ≥ 9.5, and Eh ≤ +150mV; If pH ≤ 7.5 or pH ≥ 9.5, the pH value is considered to have changed abnormally. If Eh ≤ +150mV, then the redox potential Eh detection value is considered to have changed abnormally.

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