A system and method for storing hydrogen and preparing clean energy using abandoned mines

Abstract

The present invention discloses a system and method for storing hydrogen and preparing clean energy by using abandoned mines. The system includes abandoned mines for preparation and storage. The waste gas mine is provided with a closed rock layer, and the inner top is provided with a water-bearing stratum, a cap layer and an ore layer in sequence from top to bottom; the waste gas mine for preparation is provided with a small molecule mesh screen embedded between the ore layer and the rock layer to form a first chamber and a second chamber; a first hydrogen input pipe connecting the second chamber and a first hydrogen output pipe connecting the first chamber; a pipeline connecting the catalytic container of the second chamber for generating carbon monoxide and hydrogen; a pipeline connecting the separation container of the catalytic container for separating hydrogen; a third chamber is provided in the abandoned mine for storage; a second hydrogen input pipe connected to the first hydrogen output pipe; an emptying pipe; and a multifunctional detector for detecting gas components, concentrations and pressures is provided in the above chamber. The present invention can realize large-scale hydrogen storage in abandoned underground space and clean energy conversion of carbon dioxide and methane in-situ gas.

Description

Technical Field

[0001] The present invention belongs to the technical field of comprehensive resource utilization, and specifically relates to a system and method for utilizing abandoned mines to store hydrogen and prepare clean energy. Background Art

[0002] Hydrogen-electricity conversion has the advantages of large scale and flexible regulation. When electricity is abundant, abundant renewable energy is used to generate electricity to electrolyze water to produce hydrogen, which is then stored in underground gas storage. When regulation is required, hydrogen in the gas storage is extracted and supplied to users through gas-fired power generation. On the other hand, as the amount of green coal resources decreases year by year and the number of closed / abandoned mines increases, if the huge space of closed mines is used as underground gas storage for geological storage of hydrogen energy, it will play an important role in reducing carbon emissions and increasing energy in the energy industry. Although large-scale underground hydrogen storage has broad application prospects, there are inevitably technical problems and scientific challenges in its implementation.

[0003] At the same time, after the mining of abandoned coal mines is completed, there is a large amount of carbon dioxide and methane gas in the tunnels. If these gases are not treated, it will inevitably aggravate disasters such as acid rain and global warming caused by carbon dioxide, and methane gas will also be wasted. Therefore, to achieve safe and efficient storage, it is necessary not only to evaluate and study the geological storage potential of abandoned mine space, but also to convert the carbon dioxide and methane gases in situ in the tunnels into clean energy. Summary of the invention

[0004] Technical problems to be solved: In response to the above technical problems, the present invention provides a system and method for storing hydrogen and preparing clean energy using abandoned mines, which can realize large-scale hydrogen storage and reuse of abandoned underground spaces, and can also realize clean energy conversion of in-situ gases of carbon dioxide and methane, thereby achieving efficient utilization of abandoned mines.

[0005] Technical solution: A system for storing hydrogen and preparing clean energy using abandoned mines, the system comprising: a waste gas mine for preparation and an abandoned mine for storage, the waste gas mine being provided with: a rock layer, the rock layer being a closed circle layer, the top of which is provided with a water-bearing stratum, a cap layer and an ore layer in sequence from top to bottom;

[0006] The waste gas preparation mine is provided with:

[0007] The small molecule mesh screen has its top embedded in the ore layer and its bottom embedded in the rock layer, dividing the internal space of the rock layer into a first chamber and a second chamber, and is used to screen and filter hydrogen;

[0008] A first hydrogen input pipe penetrates the top of the rock layer, and an output end is located in the second chamber, so that the gas pressure in the second chamber is higher than that in the first chamber;

[0009] A first hydrogen output pipe, which passes through the top of the rock layer, and an input end is located in the first chamber;

[0010] A catalytic container, connected by a pipeline to the bottom of the second chamber, is used to react carbon dioxide and methane to generate carbon monoxide and hydrogen;

[0011] A separation container, connected to the catalytic container by a pipeline, is provided with a hydrogen filter membrane inside for separating hydrogen;

[0012] The abandoned mine for storage is provided with:

[0013] The third chamber is formed by the internal space of the rock layer;

[0014] A second hydrogen input pipe runs through the top of the rock layer, the input end of which is connected to the first hydrogen output pipe, and the output end of which is located in the third chamber;

[0015] The drain pipe penetrates the top of the rock layer, and the input end is located in the third chamber;

[0016] The first chamber, the second chamber and the third chamber are respectively provided with a first multifunctional detector, a second multifunctional detector and a third multifunctional detector for detecting gas composition, concentration and pressure.

[0017] Preferably, a fourth multifunctional detector is provided in the catalytic container for detecting the temperature, gas composition and gas pressure in the catalytic container.

[0018] Preferably, the separation container is provided with a carbon monoxide-containing mixed gas output pipe and a second hydrogen output pipe, and the output end of the second hydrogen output pipe is connected to the first hydrogen output pipe.

[0019] Preferably, the strength and hardness of the rock layer are higher than those of the ore layer, and the sealing property of the cap layer is better than that of the rock layer.

[0020] Preferably, the sealing property of the rock layer satisfies that water in the aquifer cannot irrigate upwards under ground stress conditions.

[0021] Preferably, the porosity of the ore layer satisfies that: under the action of gas pressure, the liquid and gas seeping in the ore layer are relatively balanced, so that the liquid in the ore layer cannot drip downwards and the gas cannot move upwards over the cap layer.

[0022] Preferably, the hydrogen filter membrane is connected to the separation container by means of inlaying and covering.

[0023] Preferably, the output end of the exhaust pipe is connected to the catalytic container.

[0024] A method for storing hydrogen and preparing clean energy using abandoned mines comprises the following steps:

[0025] S1. The hydrogen mixed gas obtained by electrolysis of water is input into the second chamber through the first hydrogen input pipe, so that the gas pressure in the second chamber is higher than that in the first chamber. Under the action of the pressure difference, the hydrogen enters the first chamber through the small molecule mesh screen, and the gas in the first chamber enters the third chamber through the first hydrogen output pipe, and the gas in the third chamber is discharged through the exhaust pipe;

[0026] S2. The remaining mixed gas in the second chamber enters the catalytic container under the action of pressure difference, and reacts carbon dioxide and methane to generate carbon monoxide and hydrogen through methane dry reforming reaction. The mixed gas after the reaction enters the separation container and passes through the hydrogen filter membrane to separate hydrogen, thereby realizing the preparation of clean energy;

[0027] S3. The gas composition, concentration and pressure of the first chamber, the second chamber and the third chamber are detected by the first multifunctional detector, the second multifunctional detector and the third multifunctional detector. When the hydrogen concentration reaches the storage requirement, the first hydrogen input pipe and the exhaust pipe are closed to realize the storage of hydrogen.

[0028] Preferably, the hydrogen separated in the separation container is introduced into the first hydrogen output pipe through a pipeline.

[0029] Beneficial effects: The waste gas mine of the present invention is provided with a water-bearing stratum, a cap layer and an ore layer, and has unique geological conditions for preventing gas leakage. The water-bearing stratum forms a natural water seal, which prevents gas leakage and isolates the inflow of outside air. The gas flowing in the ore layer is affected by the low porosity of the ore layer. Under the action of air pressure, it maintains a relative balance with the seepage liquid, so that the liquid in the ore layer cannot drip downward and the gas cannot move up over the cap layer.

[0030] At the same time, the two sides of the small molecule mesh screen can quickly separate and purify hydrogen under the action of pressure difference, and the unpurified gas will be mixed with the original carbon dioxide, methane and other gases in the second chamber. The mixed gas will undergo a chemical reaction in the catalytic container to generate carbon monoxide and hydrogen, and finally the gas will be separated in the separation container. All gas flows in the entire invention system are completed under the action of pressure difference or concentration difference. It can not only quickly purify hydrogen and complete the collection of hydrogen, but also make full use of the abandoned mine space and realize the reasonable reuse of underground abandoned space. More importantly, the system realizes the clean energy conversion of carbon dioxide and methane existing in situ in the abandoned space through chemical catalysis. This method will provide a potential large-space hydrogen storage solution for the reuse of abandoned underground space. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the structure of the present invention;

[0032] The numerical labels in the figure represent the following: 1. rock layer; 2. water-bearing stratum; 3. cap layer; 4. ore layer; 5. small molecule mesh screen; 6. first chamber; 7. second chamber; 8. first hydrogen input pipe; 9. first hydrogen output pipe; 10. catalytic container; 11. separation container; 12. hydrogen filter membrane; 13. third chamber; 14. second hydrogen input pipe; 15. exhaust pipe; 16. first multifunctional detector; 17. second multifunctional detector; 18. third multifunctional detector; 19. fourth multifunctional detector; 20. carbon monoxide-containing mixed gas output pipe; 21. second hydrogen output pipe. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments. Example 1

[0034] like Figure 1 As shown, the present invention provides a system for storing hydrogen and preparing clean energy using abandoned mines, and the system includes: a waste gas mine for preparation and an abandoned mine for storage. The waste gas mine is provided with: a rock layer 1, the rock layer 1 is a closed circle layer, and the top of the rock layer 1 is provided with a water-bearing stratum 2, a cap layer 3 and an irregular ore layer 4 caused by excavation from top to bottom. The rock physical properties of the rock layer 1 are relatively good, and its strength and hardness are higher than those of the ore layer 4; in addition, the rock layer 1 has good sealing properties, which meets the condition that the water in the water-bearing stratum 2 cannot be irrigated upward under the ground stress condition, and the cap layer 3 has better sealing properties than the rock layer 1, thereby effectively isolating the circulation of external air and internal gas. The ore layer 4 has a low porosity and meets the following conditions: under the action of air pressure, the liquid and gas seeping in the ore layer 4 are relatively balanced, so that the liquid in the ore layer 4 cannot drip downward, and the gas cannot move upward over the cap layer 3.

[0035] The waste gas preparation mine is provided with:

[0036] A small molecule mesh screen 5, the top of which is embedded in the ore layer 4, and the bottom of which is embedded in the rock layer 1, so as to divide the inner space of the rock layer 1 into a first chamber 6 and a second chamber 7, for screening and filtering hydrogen;

[0037] A first hydrogen input pipe 8 passes through the top of the rock layer 1, and an output end is located in the second chamber 7, so that the gas pressure in the second chamber 7 is higher than that in the first chamber 6;

[0038] A first hydrogen output pipe 9 passes through the top of the rock layer 1, and an input end is located in the first chamber 6;

[0039] The catalytic container 10 is connected to the bottom of the second chamber 7 by a pipeline and is used to react carbon dioxide and methane to generate carbon monoxide and hydrogen;

[0040] A separation container 11 is connected to the catalytic container 10 through a pipeline and is provided with a hydrogen filter membrane 12 inside for separating hydrogen;

[0041] The abandoned mine for storage is provided with:

[0042] The third chamber 13 is formed by the inner space of the rock layer 1;

[0043] The second hydrogen input pipe 14 passes through the top of the rock layer 1, the input end is connected to the first hydrogen output pipe 9, and the output end is arranged in the third chamber 13;

[0044] The exhaust pipe 15 passes through the top of the rock layer 1, the input end is arranged in the third chamber 13, and the output end is connected to the catalytic container 10, so that the original mixed gas in the third chamber 13 can be pushed into the catalytic container 10 for reaction;

[0045] The first chamber 6, the second chamber 7 and the third chamber 13 are respectively provided with a first multifunctional detector 16, a second multifunctional detector 17 and a third multifunctional detector 18 for detecting gas composition, concentration and pressure.

[0046] The catalytic container 10 is provided with a fourth multifunctional detector 19 for detecting the temperature, gas composition and gas pressure in the catalytic container 10. The separation container 11 is provided with a carbon monoxide mixed gas output pipe 20 and a second hydrogen output pipe 21, and the output end of the second hydrogen output pipe 21 is connected to the first hydrogen output pipe 9. The hydrogen filter membrane 12 is connected to the separation container 11 by means of inlaying and covering.

[0047] The method for storing hydrogen in abandoned mines and preparing clean energy using the above system comprises the following steps:

[0048] First, the hydrogen mixed gas with a lower concentration obtained by electrolysis of water is input into the second chamber 7 through the first hydrogen input pipe 8, and the second multifunctional detector 17 starts to detect the concentration of hydrogen and the gas pressure of the mixed gas. Since the internal pressure of the second chamber 7 is relatively high at this time, the mixed gas begins to diffuse upward along the ore layer 4 with more pores. When it diffuses to the position of the cap layer 3, a water seal barrier is naturally formed because the top of the cap layer 3 is the water-bearing stratum 2. At the same time, the second multifunctional detector 17 realizes the dynamic balance of gas and water in the ore layer 4 by controlling the pressure of the mixed gas. At this time, the gas pressure in the second chamber 7 is significantly higher than that in the first chamber 6. Under the action of the pressure difference, the hydrogen in the second chamber 7 enters the first chamber 6 through the small molecule mesh sieve 5 that only allows hydrogen to pass through, and the gas in the first chamber 6 enters the third chamber 13 through the first hydrogen output pipe 9. The gas in the third chamber 13 is discharged through the exhaust pipe 15, and the gas in the first chamber 6 and the third chamber 13 is gradually replaced by purified hydrogen. In this process, the first multifunctional detector 16 and the second multifunctional detector 17 always monitor the pressure in the first chamber 6 and the second chamber 7 in real time to ensure that the pressure in the second chamber 7 is always greater than the pressure in the first chamber 6, thereby ensuring the flow direction of the gas.

[0049] Due to the pressurization of the gas supplemented by the first hydrogen inlet pipe 8, the remaining mixed gas in the second chamber 7 enters the catalytic container 10 under the action of the pressure difference; at the same time, as the gas from the second hydrogen inlet pipe 14 enters the third chamber 13, the original mixed gas in the third chamber 13 enters the catalytic container 10 through the exhaust pipe 15 under the action of the pressure difference. It should be noted that the waste gas in the mine mainly contains carbon dioxide and methane, which means that the gas entering the catalytic container 10 at this time is mainly carbon dioxide, methane and hydrogen. Therefore, carbon dioxide and methane can be reacted to generate carbon monoxide and hydrogen through the methane dry reforming reaction in the catalytic container 10. The main catalyst in the catalytic container 10 is Ni / MgCe 0.12 O x , the catalyst has very excellent performance in terms of activity and stability in methane dry reforming reaction technology. At the same time, because providing an appropriate temperature in the catalytic container 10 is more conducive to catalytic efficiency, the temperature, gas composition and gas pressure in the catalytic container 10 are detected by the fourth multifunctional detector 19 to promote the reaction. The mixed gas after the reaction is mainly carbon monoxide and hydrogen. After entering the separation container 11, it passes through the hydrogen filter membrane 12 to separate hydrogen, thereby completely realizing the preparation of clean energy. The hydrogen separated in the separation container 11 can be incorporated into the first hydrogen output pipe 9 through the second hydrogen output pipe 21 for storage together. The remaining mixed gas containing carbon monoxide can be recycled after being discharged.

[0050] The gas composition, concentration and pressure of the first chamber 6, the second chamber 7 and the third chamber 13 are detected by the first multifunctional detector 16, the second multifunctional detector 17 and the third multifunctional detector 18. When the hydrogen purity reaches the storage requirement, the valves of the first hydrogen inlet pipe 8 and the exhaust pipe 15 are closed to realize the storage of hydrogen.

Claims

1. A system for storing hydrogen and preparing clean energy using abandoned mines, characterized in that: The system comprises: an abandoned mine for preparation and an abandoned mine for storage, wherein the abandoned mine is provided with: a rock layer (1), wherein the rock layer (1) is a closed circle layer, wherein the top of the rock layer is provided with a water-bearing stratum (2), a cap layer (3) and an ore layer (4) in order from top to bottom; the strength and hardness of the rock layer (1) are both higher than those of the ore layer (4), and the sealing property of the cap layer (3) is better than that of the rock layer (1); the sealing property of the rock layer (1) satisfies that: water in the water-bearing stratum (2) cannot be irrigated upward under ground stress conditions; the porosity of the ore layer (4) satisfies that: under the action of gas pressure, the liquid and gas seeping in the ore layer (4) are relatively balanced, so that the liquid in the ore layer (4) cannot drip downward and the gas cannot move upward over the cap layer (3); The abandoned mine shaft for preparation is provided with: A small molecule mesh screen (5) with a top end embedded in the ore layer (4) and a bottom end embedded in the rock layer (1), dividing the internal space of the rock layer (1) into a first chamber (6) and a second chamber (7), for screening and filtering hydrogen; A first hydrogen input pipe (8) passes through the top of the rock layer (1), and the output end is located in the second chamber (7), so that the gas pressure in the second chamber (7) is higher than that in the first chamber (6); A first hydrogen output pipe (9) passes through the top of the rock layer (1), and an input end is located in the first chamber (6); A catalytic container (10) connected to the bottom of the second chamber (7) via a pipeline and used for reacting carbon dioxide and methane to generate carbon monoxide and hydrogen; A separation container (11) is connected to the catalytic container (10) through a pipeline and is provided with a hydrogen filter membrane (12) inside for separating hydrogen; The abandoned mine for storage is provided with: The third chamber (13) is formed by the inner space of the rock layer (1); A second hydrogen input pipe (14) passes through the top of the rock layer (1), the input end of which is connected to the first hydrogen output pipe (9), and the output end of which is arranged in the third chamber (13); An exhaust pipe (15) passes through the top of the rock layer (1), and an input end is arranged in the third chamber (13); A first multifunctional detector (16), a second multifunctional detector (17) and a third multifunctional detector (18) for detecting gas composition, concentration and pressure are respectively arranged in the first chamber (6), the second chamber (7) and the third chamber (13).

2. A system for storing hydrogen and preparing clean energy using abandoned mines according to claim 1, characterized in that: A fourth multifunctional detector (19) is provided in the catalytic container (10) for detecting the temperature, gas composition and gas pressure in the catalytic container (10).

3. The system for storing hydrogen and preparing clean energy by using abandoned mines according to claim 1, characterized in that: The separation container (11) is provided with a carbon monoxide-containing mixed gas output pipe (20) and a second hydrogen output pipe (21), and the output end of the second hydrogen output pipe (21) is connected to the first hydrogen output pipe (9).

4. The system for storing hydrogen and preparing clean energy by utilizing abandoned mines according to claim 1, characterized in that: The hydrogen filter membrane (12) is connected to the separation container (11) by means of embedding, covering and pressing.

5. The system for storing hydrogen and preparing clean energy by utilizing abandoned mines according to claim 1, characterized in that: The output end of the exhaust pipe (15) is connected to the catalytic container (10).

6. The working method of the system for storing hydrogen and preparing clean energy by utilizing abandoned mines as claimed in claim 1, characterized in that: The steps include: S1. The hydrogen mixed gas obtained by electrolysis of water is input into the second chamber (7) through the first hydrogen input pipe (8), so that the gas pressure in the second chamber (7) is higher than that in the first chamber (6). Under the action of the pressure difference, the hydrogen enters the first chamber (6) through the small molecule mesh screen (5), and the gas in the first chamber (6) enters the third chamber (13) through the first hydrogen output pipe (9), and the gas in the third chamber (13) is discharged through the exhaust pipe (15); S2. The remaining mixed gas in the second chamber (7) enters the catalytic container (10) under the action of the pressure difference, and reacts carbon dioxide and methane to generate carbon monoxide and hydrogen through a methane dry reforming reaction. The mixed gas after the reaction enters the separation container (11), passes through the hydrogen filter membrane (12), and separates hydrogen, thereby realizing the preparation of clean energy; S3. The gas composition, concentration and pressure of the first chamber (6), the second chamber (7) and the third chamber (13) are detected by the first multifunctional detector (16), the second multifunctional detector (17) and the third multifunctional detector (18). When the hydrogen concentration reaches the storage requirement, the first hydrogen input pipe (8) and the exhaust pipe (15) are closed, thereby realizing the storage of hydrogen.

7. The working method of the system for storing hydrogen and preparing clean energy by utilizing abandoned mines according to claim 6, characterized in that: The hydrogen separated in the separation container (11) is introduced into the first hydrogen output pipe (9) through a pipeline.

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