Method for integrating closed mine in-situ electrolytic hydrogen production, underground energy storage and burning explosion power generation

Abstract

The invention discloses a closed mine in-situ electrolytic hydrogen production-underground energy storage-blast power generation integrated method, which comprises the following steps: firstly, building a mine water underground reservoir in a closed mine, carrying out deep treatment on mine water, and finally, continuously converting the mine water into hydrogen by adopting an electrolytic hydrogen production mode to realize in-situ electrolytic hydrogen production of the mine water. Then a roadway of the closed mine is transformed to form an underground hydrogen storage space used for storing prepared hydrogen; when stable power supply is needed, the hydrogen is conveyed to the explosion engine and combined with the pulverized coal, and pulverized coal-hydrogen mixed explosion power generation is carried out; and products generated after explosion power generation are collected, and resources are recycled after the products are classified. According to the system, mine water resources, closed mine underground space resources and surplus wind and light power are matched with one another, electric energy is converted and stored when being surplus and is released and supplemented in time when needing to be supplemented, and therefore it is guaranteed that electric energy is stably supplied under various weather conditions while waste resources are effectively utilized.

Description

Technical Field

[0001] The present invention relates to the technical field of utilization of underground water resources in closed mines, and particularly to an integrated method for in-situ electrolytic hydrogen production - underground energy storage - combustion power generation in closed mines. Background Art

[0002] During the coal mining process, all the water seeping into the underground mining space of the mine is called mine water. According to statistics, the average water-rich coefficient of coal mines in China is about 1.87, that is, about 1.87 tons of mine water is generated per ton of coal mined. Facing the huge total amount of coal mine water resources, the current utilization rate is significantly low, only 35%. With the continuous increase in the number of closed mines, problems such as environmental pollution and water inrush accidents caused by improper underground water treatment emerge in an endless stream. How to correctly handle mine water resources and improve the utilization efficiency is an issue to be solved for the sustainable and healthy development of the mining economy. Currently, in-situ electrolytic hydrogen production using mine water is expected to become a new method for improving the utilization rate of underground water resources. However, the produced hydrogen has problems of difficult storage and transportation due to its low density and easy combustion characteristics. At the same time, the space resources in closed mines have not been effectively utilized, which has triggered the thinking of how to realize the in-situ storage and utilization of hydrogen energy underground.

[0003] Currently, new energy power generation technologies represented by wind power and photovoltaic power are greatly affected by factors such as climate change, and the power generation is intermittent and volatile, making it difficult to connect to the power grid. As a result, the phenomena of abandoned wind and abandoned light are very prominent, and there is a large amount of surplus electric energy. In this case, how to improve the consumption capacity of wind and photovoltaic power generation and convert unstable wind and photovoltaic power into stable thermal power is an urgent problem to be solved to avoid energy retention and waste and achieve stable power supply under various weather conditions.

[0004] In summary, it is necessary to find a comprehensive method to systematically solve the problems of utilization of mine water resources, utilization of underground space resources in closed mines, and utilization of surplus production capacity of wind and photovoltaic power, which is the research direction required by the present invention. Summary of the Invention

[0005] Aiming at the problems existing in the above-mentioned prior art, the present invention provides an integrated method for in-situ electrolytic hydrogen production - underground energy storage - combustion power generation in closed mines, which coordinates the mine water resources, underground space resources in closed mines, and surplus production capacity of wind and photovoltaic power to realize conversion and storage when there is surplus electric energy and timely release and supplement when needed, so as to realize the effective utilization of waste resources and ensure stable power supply under various weather conditions.

[0006] To achieve the above object, the technical solution adopted by the present invention is: an integrated method for in-situ electrolytic hydrogen production - underground energy storage - combustion power generation in closed mines, comprising the following steps:

[0007] Step 1. In-situ electrolysis of mine water to produce hydrogen: Build an underground reservoir for mine water in a closed mine, and use the evaporation crystallization technology to deeply treat the mine water. Finally, in the closed mine, electrolyze the treated mine water to continuously convert it into hydrogen;

[0008] Step 2. Underground hydrogen energy storage: Transform the roadway of the closed mine to form an underground space for storing hydrogen, and use it to store the hydrogen prepared in Step 1 after compression;

[0009] Step 3. Solid-gas hybrid combustion power generation: When stable power supply is required, transport the hydrogen stored in Step 2 to the combustion explosion engine and combine it with the pulverized coal collected in the closed mine to carry out hybrid combustion power generation of pulverized coal-hydrogen;

[0010] Step 4. Recycling of product resources: Collect the products after combustion power generation in Step 3, classify the products, and recycle the resources.

[0011] Furthermore, the specific content of Step 1 is as follows:

[0012] 1.1 Building an underground reservoir for mine water: According to the hydrogeological survey data, build an underground reservoir for mine water in the goaf of the closed mine, and make the underground reservoir for mine water be below the aquifer. At the same time, use safety coal pillars and build artificial dams to prevent the leakage of water sources in the reservoir; The mine water in the aquifer flows from a high place to the underground reservoir for mine water, and a large amount of suspended debris is removed by the adsorption of caving rock mass in the goaf and the filtration of fissures and separated strata spaces during the flowing process, and finally flows into the underground reservoir for mine water to realize the preliminary purification and storage of mine water;

[0013] 1.2 Deep treatment of mine water: Transport the mine water in the underground reservoir for mine water to the evaporation crystallization device. The evaporation crystallization device separates the water and salt in the mine water by heating evaporation, and after obtaining high-purity water vapor, it is introduced into the distillation water tank for cooling to be used as the water source for electrolysis to produce hydrogen;

[0014] 1.3 In-situ electrolysis of mine water to produce hydrogen: Introduce the water in the distillation water tank into the electrolysis device to produce hydrogen and oxygen resources, and realize in-situ electrolysis of mine water in the underground mine to produce hydrogen.

[0015] Furthermore, to improve the efficiency of electrolyzing mine water to produce hydrogen, the quality of the treated mine water in the distillation water tank should meet the following requirements according to the national standard "Technical Requirements for Water Electrolysis Hydrogen Production System" (GB / T 19774-2005): resistivity ≥ 1.0×10 5 Ω·cm, iron ion content < 1.0 mg / L, chloride ion content < 2.0 mg / L, suspended matter content < 1.0 mg / L.

[0016] Further, the electrolytic hydrogen production device uses an aqueous KOH solution as the electrolyte, which has the characteristics of low saturated vapor pressure, high conductivity, and electrochemical stability; the quality requirements of the electrolyte meet (GB / T 19774-2005): the concentration range is 27%-32%, the content < 100 mg / L, and the content < 3 mg / L, the content < 800 mg / L. The device is matched with an alkaline electrolytic cell, and the working environment temperature < 45 °C.

[0017] Further, the specific content of the second step is as follows:

[0018] 2.1. Roadway transformation: Conduct a feasibility assessment on the underground roadway of the closed mine, and preferentially select low-permeability rock formations to ensure the stability, sealing performance, and compressive capacity of the roadway surrounding rock structure are suitable for storing high-pressure hydrogen; adopt a multi-layer lining structure to achieve roadway reinforcement and sealing transformation. Concrete sealing walls are built on both sides of the roadway, and gas transmission pipeline holes are reserved. A hydrogen transmission pipeline is built in the roadway, and nano-materials are filled between the holes of the sealing wall and the pipeline for re-sealing to form an underground hydrogen storage space; an oxygen transmission pipeline is built on the rock formation below the underground hydrogen storage space, and one end of the hydrogen transmission pipeline and one end of the oxygen transmission pipeline are respectively connected to the hydrogen outlet and oxygen outlet of the electrolytic hydrogen production device;

[0019] 2.2. Compressed hydrogen energy storage: After the transformation of the underground hydrogen storage space is completed, monitor the residual gas components in the underground hydrogen storage space and conduct extraction and removal; use a gas compressor to raise the hydrogen produced by electrolysis to a high-pressure state and introduce it into the underground hydrogen storage space for storage, and control the hydrogen gas pressure in the underground hydrogen storage space at 10-15 MPa to achieve in-situ underground storage of hydrogen.

[0020] Further, the multi-layer lining structure includes an inner lining and an outer lining. The inner lining material is a polymer, and the outer lining material is concrete; the inner lining matches the cross-sectional shape of the roadway and is rigidly fixed to the inner wall of the roadway. At the same time, a certain space is reserved between the inner lining and the inner wall of the roadway for pouring concrete to form the outer lining. Among them, the polymer inner lining has the advantages of high strength and low hydrogen permeability.

[0021] Further, the specific content of the third step is as follows: When stable power supply is required under extreme weather or high grid load conditions, inject the high-pressure hydrogen in the underground hydrogen storage space into the combustion chamber of the detonation engine through a pipeline, and at the same time introduce oxygen into the combustion chamber through the oxygen transmission pipeline and cooperate with crushed coal powder. Use an electric spark ignition method to cause the explosion combustion of hydrogen and oxygen, and at the same time cause the detonation of coal powder. The large amount of energy released is converted into mechanical energy to achieve hybrid detonation power generation of coal powder-hydrogen.

[0022] Further, the pulverized coal is input into the combustion explosion chamber in a classified distribution manner; first, the coarse-grained pulverized coal is transported into the combustion explosion chamber to increase the contact area with the mixed hydrogen and oxygen, and quickly initiate the initial combustion explosion process; then, the fine-grained pulverized coal is transported into the combustion explosion chamber to extend the combustion explosion time and form a stable combustion explosion process; among them, the feeding amount of the coarse-grained pulverized coal accounts for 20% of the total amount of pulverized coal, and the feeding amount of the fine-grained pulverized coal accounts for 80% of the total amount of pulverized coal.

[0023] Further, the specific content of step four is as follows:

[0024] 4.1. Collect the products of combustion explosion power generation: The main products after combustion explosion power generation are carbon dioxide gas and water; a carbon dioxide gas capture device is used to collect the carbon dioxide in the flue gas generated in the combustion explosion engine, and at the same time, the generated clean water is recovered to the ground;

[0025] 4.2. Recycling and resource utilization: The collected carbon dioxide gas is stored in a storage tank as a fire extinguisher for fire prevention and extinguishing in the underground hydrogen storage space; the clean water recovered to the ground is used in other industrial production processes.

[0026] Further, the electric energy required for each process of underground evaporation and crystallization treatment of mine water, electrolysis of mine water to produce hydrogen, and hydrogen compression treatment in steps one and two is supplied by surplus wind and photovoltaic power; that is, the evaporation and crystallization device, the electrolysis hydrogen production device, and the gas compressor are all powered by wind power and photovoltaic power generation units, and the surplus wind and photovoltaic power are used to supply each equipment, converting the effectively wasted wind and light energy into hydrogen production to achieve the storage of chemical energy.

[0027] Compared with the prior art, the specific advantages of the present invention are as follows:

[0028] 1. By establishing an underground storage reservoir for mine water, the present invention realizes the direct underground treatment of mine water, effectively reducing the costs of pump lifting and pipeline external discharge in traditional surface treatment. And by utilizing the self-purification effect of the underground storage reservoir for mine water, the present invention realizes the large-scale and low-cost removal of suspended impurities in mine water, while storing water resources; and through the layout position of the underground storage reservoir for mine water, after filtering the mine water using the existing geological structure and combining with evaporation and crystallization to achieve water-salt separation, ensuring that the mine water can meet the requirements for electrolysis hydrogen production and providing a pure water source for subsequent electrolysis hydrogen production. This method greatly improves the utilization rate of underground water resources and can ensure the efficiency of hydrogen production.

[0029] 2. By reconstructing the roadway space in the closed mine for the second time, the present invention constructs an underground hydrogen storage space, enabling the hydrogen generated by electrolysis hydrogen production to be directly stored underground, effectively playing the role of the available space resources in the closed mine and solving the problem of difficult traditional hydrogen storage and transportation.

[0030] 3. The present invention utilizes wind power and photovoltaic power generation sets, and uses the surplus wind and photovoltaic power for the deep treatment of mine water, electrolytic hydrogen production, and compressed hydrogen energy storage processes, effectively solving the problems of abandoned wind and abandoned light, and improving the consumption capacity of new energy. At the same time, with the help of combustion power generation technology, the conversion of new energy is realized. The unstable wind and photovoltaic power are first converted into chemical energy (i.e., hydrogen), and then into stable thermal power (i.e., combustion power generation), achieving stable power supply under multiple environmental conditions.

[0031] 4. The present invention realizes the in-situ utilization of hydrogen energy by combustion power generation, uses the explosion limit range when hydrogen and oxygen are mixed to assist in the combustion explosion of pulverized coal, and due to the mixed combustion of hydrogen, the combustion reaction in the combustion explosion engine is more complete. The main components of the flue gas generated by complete combustion are carbon dioxide and water, reducing the content of harmful gases generated by incomplete combustion of pulverized coal and reducing the gas separation and treatment cost.

[0032] 5. The present invention collects the carbon dioxide gas generated by combustion explosion and uses it for fire prevention in the underground hydrogen storage space. The recovery process reduces carbon dioxide emissions and alleviates the greenhouse effect; at the same time, the clean water generated by combustion power generation is recycled, realizing the purification and reuse of water resources. Brief Description of the Drawings

[0033] Figure 1 is a schematic diagram of the in-situ electrolytic hydrogen production system for mine water in the present invention;

[0034] Figure 2 is a schematic diagram of underground hydrogen energy storage in the present invention;

[0035] Figure 3 is a schematic diagram of the combustion explosion power generation of pulverized coal - hydrogen mixture and the recycling of products in the present invention.

[0036] In the figure: 1. Underground storage of mine water, 2. Safety coal pillar, 3. Artificial dam body, 4. Evaporation and crystallization device, 5. Distillation water tank, 6. Electrolytic hydrogen production device, 7. Hydrogen transmission pipeline, 8. Oxygen transmission pipeline, 9. Wind power and photovoltaic power generation sets, 10. Inner lining, 11. Outer lining, 12. Underground hydrogen storage space, 13. Sealing wall, 14. Nanomaterial, 15. Gas compressor, 16. Power grid, 17. Combustion explosion engine, 18. Pulverized coal, 19. Carbon dioxide gas capture device, 20. Storage tank, 21. Clean water. Detailed Embodiments

[0037] The present invention will be further described below.

[0038] As shown in the figure, the present invention includes the following steps:

[0039] Step 1. In-situ electrolysis of mine water to produce hydrogen: Build an underground reservoir 1 for mine water in a closed mine, and use the evaporation crystallization technology to deeply treat the mine water. Finally, in the closed mine, the treated mine water is electrolyzed to continuously convert it into hydrogen, as Figure 1 shown. Specifically:

[0040] 1.1 Build an underground reservoir for mine water: According to the hydrogeological survey data, build an underground reservoir 1 for mine water in the goaf of the closed mine, and make the underground reservoir 1 for mine water below the aquifer. At the same time, use the safety coal pillar 2 and build an artificial dam 3 to prevent the leakage of water in the reservoir; The mine water in the aquifer flows from a high place to the underground reservoir 1 for mine water, and a large amount of suspended debris is removed by the adsorption of caving rock mass in the goaf and the filtration of fissures and separated strata space during the flowing process, and finally flows into the underground reservoir 1 for mine water to realize the preliminary purification and storage of mine water;

[0041] 1.2 Deep treatment of mine water: Transport the mine water in the underground reservoir 1 for mine water to the evaporation crystallization device 4. The evaporation crystallization device 4 separates water and salt in the mine water by heating and evaporation, and after obtaining high-purity water vapor, it is cooled in the distillation water tank 5 as the water source for electrolysis to produce hydrogen;

[0042] 1.3 In-situ electrolysis of mine water to produce hydrogen: Transport the water in the distillation water tank 5 into the electrolysis device 6 for hydrogen production, and then hydrogen and oxygen resources are produced to realize in-situ electrolysis of underground mine water to produce hydrogen.

[0043] To improve the efficiency of electrolyzing mine water to produce hydrogen, the quality of the treated mine water in the distillation water tank 5 needs to meet the following requirements according to the national standard "Technical Requirements for Hydrogen Production System by Water Electrolysis" (GB / T 19774-2005): resistivity ≥ 1.0×10 5 Ω·cm, iron ion content < 1.0 mg / L, chloride ion content < 2.0 mg / L, suspended matter content < 1.0 mg / L; The electrolysis device 6 for hydrogen production uses KOH aqueous solution as the electrolyte, and this electrolyte has the characteristics of low saturated vapor pressure, high conductivity, and electrochemical stability; The quality requirements of the electrolyte meet (GB / T 19774-2005): the concentration range is 27%-32%, content < 100 mg / L, , content < 3 mg / L, content < 800 mg / L. The device is matched with an alkaline electrolytic cell, and the working environment temperature < 45 °C.

[0044] Step 2. Underground energy storage of hydrogen: As Figure 2 shown, transform the roadway of the closed mine to form an underground space 12 for storing hydrogen, which is used to compress and store the hydrogen prepared in Step 1. Specifically:

[0045] 2.1. Roadway renovation: Conduct a feasibility assessment on the underground roadways of the closed mine. Prioritize the selection of low-permeability rock strata to ensure that the surrounding rock structure of the roadway has stability, tightness, and compressive capacity suitable for storing high-pressure hydrogen. Adopt a multi-layer lining structure to achieve roadway reinforcement and sealing renovation. Concrete sealing walls 13 are built on both sides of the roadway with gas transmission pipeline holes reserved, and a hydrogen transmission pipeline 7 is erected in the roadway. The space between the sealing wall 13 and the pipeline holes is filled with nanomaterials 14 for secondary sealing to form an underground hydrogen storage space 12. An oxygen transmission pipeline 8 is erected in the rock strata below the underground hydrogen storage space 12. One end of the hydrogen transmission pipeline 7 and one end of the oxygen transmission pipeline 8 are respectively connected to the hydrogen outlet and oxygen outlet of the electrolytic hydrogen production device 6. The multi-layer lining structure includes an inner lining 10 and an outer lining 11. The inner lining is made of a polymer material, and the outer lining material is concrete. The inner lining 10 matches the cross-sectional shape of the roadway and is rigidly fixed to the inner wall of the roadway. At the same time, a certain space is reserved between the inner lining 10 and the inner wall of the roadway for pouring concrete to form the outer lining 11. Among them, the polymer inner lining has the advantages of high strength and low hydrogen permeability.

[0046] 2.2. Compressed hydrogen energy storage: After the renovation of the underground hydrogen storage space 12 is completed, monitor the residual gas components in the underground hydrogen storage space 12 and conduct extraction and removal. Use a gas compressor 15 to boost the electrolytically produced hydrogen to a high-pressure state and introduce it into the underground hydrogen storage space 12 for storage, and control the hydrogen gas pressure in the underground hydrogen storage space 12 at 10 - 15 MPa to achieve in-situ underground storage of hydrogen.

[0047] Step 3. Solid-gas hybrid combustion power generation: When stable power supply is required, transport the hydrogen stored in Step 2 to the combustion explosion engine 17 and combine it with the pulverized coal collected in the closed mine for hybrid combustion power generation of pulverized coal - hydrogen, as Figure 3 shown. Specifically, when stable power supply is required under extreme weather or high-load conditions of the power grid 16, inject the high-pressure hydrogen in the underground hydrogen storage space 12 into the combustion explosion chamber of the combustion explosion engine 17 through a pipeline. At the same time, introduce oxygen into the combustion explosion chamber through the oxygen transmission pipeline 8 and cooperate with crushed pulverized coal 18. To ensure the sustainability of the combustion explosion process, the proportion of hydrogen introduced into the combustion explosion chamber in the mixed gas is controlled within the explosion limit range of 4% - 74.2%. Adopt the method of spark ignition to cause the explosion combustion of hydrogen and oxygen, and at the same time cause the combustion explosion of pulverized coal. The large amount of energy released is converted into mechanical energy to achieve hybrid combustion power generation of pulverized coal - hydrogen. The pulverized coal is input into the combustion explosion chamber by means of hierarchical distribution. First, transport the coarse-grained pulverized coal to the combustion explosion chamber to increase the contact area with the mixed hydrogen and oxygen and quickly initiate the initial combustion explosion process. Then transport the fine-grained pulverized coal to the combustion explosion chamber to extend the combustion explosion time and form a stable combustion explosion process. Among them, the feeding amount of the coarse-grained pulverized coal accounts for 20% of the total amount of pulverized coal, and the feeding amount of the fine-grained pulverized coal accounts for 80% of the total amount of pulverized coal.

[0048] Step 4. Recycling of product resources: Collect the products after combustion power generation in Step 3, classify the products and then recycle the resources. For example, Figure 3 as shown in

[0049] 4.1 Collection of combustion power generation products: The main products after combustion power generation are carbon dioxide gas and water. A carbon dioxide gas capture device 19 is used to collect carbon dioxide in the flue gas generated in the combustion engine 17. At the same time, the generated clean water is recovered to the ground.

[0050] 4.2 Recycling of resources: The collected carbon dioxide gas is stored in a storage tank 20 as a fire extinguisher for fire prevention and extinguishing in the underground hydrogen storage space 12. The clean water recovered to the ground is used in other industrial production processes.

[0051] The electric energy required for each process of the above-mentioned evaporation and crystallization treatment of mine water, electrolysis of mine water to produce hydrogen, and hydrogen compression treatment is supplied by surplus wind and photovoltaic power. That is, the evaporation and crystallization device 4, the electrolysis hydrogen production device 6, and the gas compressor 15 are all powered by wind and photovoltaic power generation sets 9. The surplus wind and photovoltaic power are used to supply each equipment, and the effectively wasted wind and light energy is converted into hydrogen production to achieve the storage of chemical energy.

[0052] In addition, the evaporation and crystallization device 4, the distillation water tank 5, the electrolysis hydrogen production device 6, the wind and photovoltaic power generation sets 9, the gas compressor 15, the combustion engine 17, the carbon dioxide gas capture device 19, and the storage tank 20 are all existing equipment and can be directly purchased from the market. The present invention only utilizes their existing functions and does not improve their structures.

[0053] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for integrating in-situ electrolytic hydrogen production - underground energy storage - combustion power generation in a closed mine, characterized in that, It includes the following steps: Step 1, in-situ electrolysis of mine water to produce hydrogen: Build an underground reservoir for mine water in a closed mine, and use the evaporation crystallization technology to deeply treat the mine water. Finally, electrolyze the treated mine water in the closed mine to continuously convert the mine water into hydrogen; Step 2, underground hydrogen energy storage: Transform the roadway of the closed mine to form an underground space for storing hydrogen, which is used to compress and store the hydrogen prepared in Step 1; Step 3, solid-gas hybrid combustion power generation: When stable power supply is required, transport the hydrogen stored in Step 2 to the combustion explosion engine and combine it with the pulverized coal collected in the closed mine for hybrid combustion power generation of pulverized coal-hydrogen; Step 4, recycling of product resources: Collect the products after combustion explosion power generation in Step 3, classify the products and recycle the resources.

2. The integrated method for in-situ electrolytic hydrogen production - underground energy storage - combustion power generation in a closed mine according to claim 1, characterized in that, The specific content of Step 1 is as follows: 1.1 Build an underground reservoir for mine water: According to the hydrogeological survey data, construct an underground reservoir for mine water in the goaf of the closed mine, and make the underground reservoir for mine water be below the aquifer; The mine water in the aquifer flows from a high place to the underground reservoir for mine water, and a large amount of suspended debris is removed by the adsorption of the caving rock mass in the goaf and the filtering effect of cracks and separated layers during the flowing process, and finally flows into the underground reservoir for mine water, realizing the preliminary purification and storage of mine water; 1.2 Deep treatment of mine water: Transport the mine water in the underground reservoir for mine water to the evaporation crystallization device. The evaporation crystallization device separates the water and salt in the mine water by heating and evaporation, and after obtaining high-purity water vapor, it is introduced into the distillation water tank for cooling, serving as the water source for electrolysis to produce hydrogen; 1.3 In-situ electrolysis of mine water to produce hydrogen: Transport the water in the distillation water tank into the electrolysis device to produce hydrogen and oxygen resources, realizing in-situ electrolysis of mine water in the underground mine to produce hydrogen.

3. The integrated method for in-situ electrolytic hydrogen production - underground energy storage - combustion explosion power generation for closing a mine according to claim 2, wherein To improve the efficiency of hydrogen production by electrolyzing mine water, the quality of the treated mine water in the distillation water tank should meet the following requirements: resistivity ≥ 1.0×10 5 Ω·cm, iron ion content < 1.0 mg / L, chloride ion content < 2.0 mg / L, suspended solid content < 1.0 mg / L.

4. The integrated method for in-situ electrolytic hydrogen production - underground energy storage - combustion power generation in a closed mine according to claim 2, wherein The electrolysis device for producing hydrogen uses an aqueous KOH solution as the electrolyte.

5. The integrated method for in-situ electrolytic hydrogen production - underground energy storage - combustion power generation in a closed mine according to claim 2, wherein The specific content of Step 2 is as follows: 2.1 Roadway transformation: Conduct a feasibility assessment on the underground roadway of the closed mine, and preferably select low-permeability rock strata to ensure that the surrounding rock structure of the roadway has suitable stability, sealing performance and compressive capacity for storing high-pressure hydrogen; Adopt a multi-layer lining structure to realize the reinforcement and sealing transformation of the roadway. Concrete sealing walls are built on both sides of the roadway and gas transmission pipeline holes are reserved, and a hydrogen transmission pipeline is built in the roadway. The space between the sealing wall and the hole of the pipeline is filled with nano materials for re-sealing to form an underground space for storing hydrogen; Build an oxygen transmission pipeline on the rock stratum below the underground hydrogen storage space. One end of the hydrogen transmission pipeline and one end of the oxygen transmission pipeline are respectively connected to the hydrogen outlet and the oxygen outlet of the electrolysis device for producing hydrogen; 2.2 Compressed hydrogen energy storage: After the transformation of the underground hydrogen storage space is completed, monitor the residual gas components in the underground hydrogen storage space and conduct extraction and removal; Use a gas compressor to raise the electrolyzed hydrogen to a high-pressure state and introduce it into the underground hydrogen storage space for storage, realizing in-situ underground storage of hydrogen.

6. The integrated method for in-situ electrolytic hydrogen production - underground energy storage - combustion power generation in a closed mine according to claim 5, characterized in that The multi-layer lining structure includes an inner lining and an outer lining. The inner lining material is a polymer, and the outer lining material is concrete; The inner lining matches the cross-sectional shape of the roadway and is rigidly fixed to the inner wall of the roadway. At the same time, a certain space is reserved between the inner lining and the inner wall of the roadway for pouring concrete to form the outer lining.

7. The integrated method for in-situ electrolytic hydrogen production - underground energy storage - combustion explosion power generation for closing a mine according to claim 1, characterized in that, The specific content of Step 3 is as follows: When stable power supply is required under extreme weather conditions or high grid load conditions, high-pressure hydrogen in the underground hydrogen storage space is injected into the combustion explosion chamber of the combustion explosion engine through a pipeline. At the same time, oxygen is introduced into the combustion explosion chamber through an oxygen delivery pipeline and is used to cooperate with pulverized coal for crushing. The explosion combustion of hydrogen and oxygen is caused by means of electric spark ignition. At the same time, the pulverized coal is caused to explode and burn, and a large amount of released energy is converted into mechanical energy, realizing the hybrid combustion power generation of pulverized coal - hydrogen.

8. The integrated method for in-situ electrolytic hydrogen production - underground energy storage - combustion power generation in a closed mine according to claim 7, characterized in that The pulverized coal is input into the combustion explosion chamber in a hierarchical distribution manner; first, the coarse-grained pulverized coal is transported to the combustion explosion chamber to increase the contact area with the mixed hydrogen and oxygen and quickly initiate the initial combustion explosion process; then, the fine-grained pulverized coal is transported to the combustion explosion chamber to extend the combustion explosion time and form a stable combustion explosion process; among them, the powder feeding amount of the coarse-grained pulverized coal accounts for 20% of the total amount of pulverized coal, and the powder feeding amount of the fine-grained pulverized coal accounts for 80% of the total amount of pulverized coal.

9. The integrated method for in-situ electrolytic hydrogen production - underground energy storage - combustion power generation in a closed mine according to claim 1, characterized in that, The specific content of Step 4 is as follows: 4.

1. Collect the products of combustion power generation: The main products after combustion power generation are carbon dioxide gas and water; a carbon dioxide gas capture device is used to collect the carbon dioxide in the flue gas generated in the combustion explosion engine. At the same time, the clean water generated is recovered to the ground. 4.

2. Recycling and resource utilization: The collected carbon dioxide gas is stored in a storage tank as a fire extinguisher for fire prevention and extinguishing in the underground hydrogen storage space; the clean water recovered to the ground is used for other industrial production processes.

10. The integrated method for in-situ electrolytic hydrogen production - underground energy storage - combustion explosion power generation in a closed mine according to claim 1, wherein, The electric energy required for each process of mine water evaporation crystallization treatment, mine water electrolysis for hydrogen production, and hydrogen compression treatment in Steps 1 and 2 is supplied by surplus wind power and photovoltaic power.

Images