1. The utility model provides a system for carbon dioxide is banked up based on coal mine goaf, its characterized in that, coal mine goaf is located the caving zone, the top in caving zone is formed with the crack area in proper order and the crooked area that sinks the system includes:

a carbon dioxide temporary storage device;

the underground closed space is positioned in the caving zone and used for sealing and storing carbon dioxide, and the underground closed space is formed by surrounding a protective coal pillar, a well field boundary protective coal pillar and a closed roadway in the coal mine goaf;

the gas injection device comprises a gas injection pipeline communicated with the carbon dioxide temporary storage device, the gas injection pipeline sequentially penetrates through a bending subsidence zone and a crack zone and extends into the underground closed space;

and the monitoring device comprises a monitoring pipeline which penetrates through the bent subsidence zone and the crack zone and extends into the underground closed space.

2. The system for sequestering carbon dioxide in a coal mine gob according to claim 1, wherein the gas injection device further comprises a pressure sensor and a concentration sensor disposed in the gas injection pipeline, the monitoring device further comprises a pressure sensor and a concentration sensor disposed in the monitoring pipeline, and the system further comprises a controller connected to the pressure sensor and the concentration sensor, and a remote monitoring device connected to the controller.

3. The system for sequestering carbon dioxide in a mined-out area as defined in claim 2, further comprising power supply devices disposed on the gas injection device and the monitoring device, wherein the power supply devices are respectively connected to the pressure sensor and the concentration sensor.

4. The system for sequestering carbon dioxide in a mined out area of a coal as claimed in claim 2, wherein at least two electrically controlled safety valves are provided in the gas injection conduit and at least two back pressure relief valves are provided in the monitoring conduit.

5. The system for sequestering carbon dioxide in a coal mine gob according to claim 1, wherein the gas injection conduit communicates with a central region of the underground enclosure and the monitoring conduit communicates with a boundary region of the underground enclosure.

6. The method for sequestering carbon dioxide using the system for sequestering carbon dioxide based on a goaf of a coal mine according to any one of claims 2 to 4, comprising the steps of:

inspecting and creating the sealing condition of the coal mine goaf;

determining the positions of a gas injection hole and a monitoring hole;

according to the positions of the gas injection hole and the monitoring hole, a pipeline is arranged by drilling downwards from the ground surface above the underground closed space, and a carbon dioxide temporary storage device, a gas injection device and a monitoring device are installed and connected;

injecting carbon dioxide into the underground closed space.

7. The method for sequestering carbon dioxide according to claim 6, further comprising, prior to the steps of installing and connecting the carbon dioxide temporary storage device, the insufflation device, and the monitoring device:

and cement mortar is poured between the outer walls of the gas injection pipeline and the monitoring pipeline and the rock stratum.

8. The method of sequestering carbon dioxide of claim 6, further comprising, prior to the step of injecting carbon dioxide into the subterranean enclosed space:

and injecting air into the underground closed space until the underground closed space reaches a preset pressure value, monitoring the real-time pressure value of the underground closed space through a monitoring device, and determining whether the underground closed space meets the sealing condition or not according to the real-time pressure value and the preset pressure value.

9. The method for sequestering carbon dioxide of claim 8, wherein determining whether the underground enclosed space satisfies the sealing condition based on the real-time pressure value and the predetermined pressure value comprises:

determining that the real-time pressure value is equal to a preset pressure value, and determining that the underground closed space meets the sealing condition; or

And determining that the real-time pressure value is smaller than a preset pressure value, determining that the underground closed space does not meet the sealing condition, supplementing geological exploration, searching and determining the positions of the fault and the collapse column which are communicated with the earth surface, and then performing grouting plugging on the fault and the collapse column.

10. The method for sequestering carbon dioxide of claim 6, further comprising, prior to the step of determining that the underground enclosure meets the containment conditions:

determining that the underground closed space region does not belong to a water resource enrichment region;

the step of determining that the underground enclosed space meets the enclosed conditions comprises:

determining that the caving zone and the fissure zone are not communicated with the ground surface;

determining the positions of a fault and a collapse column which are communicated with the ground surface, and grouting and plugging the fault and the collapse column;

and (5) reinforcing and sealing the closed roadway of the coal mine goaf.

Background

At present, carbon dioxide release units in thermal power plants, coal chemical industry and the like successively start to build and put into use carbon dioxide capture and storage projects (CCS) so as to achieve the aim of carbon dioxide emission reduction. With the development and construction of many years, the industrial capture of carbon dioxide is mature, but the sealing and storing mode still does not realize breakthrough, and the current carbon dioxide sealing and storing mode includes 1, geological sealing and storing: geological sequestration is the sequestration of carbon dioxide by utilizing the gaps and containment capacity of special formations. One is to inject carbon dioxide into an oil and gas well and use the space holding capacity of the oil and gas well to store the carbon dioxide. With the research of carbon dioxide sequestration technology for more than 10 years, the mode is relatively mature. And secondly, a geological saline water layer is searched, carbon dioxide is injected at high pressure by utilizing the water body dissolving capacity and space gaps of the saline water layer, and the purpose of sequestration is realized, and the method has limited capability of sequestering carbon dioxide and is limited by geological conditions. 2. Marine sequestration: injecting the carbon dioxide into deep sea, and storing the carbon dioxide in the seabed in a form higher than the density of the seawater under the seawater pressure condition. The sea sequestration depth is typically 3000 meters at 300 atmospheres. 3. Chemical surface sealing: reacting carbon dioxide with calcium oxide or magnesium hydroxide minerals to produce carbonate solid matter. 4. Biological sealing: carbon dioxide is supplied to plants such as algae and forests, and is consumed by photosynthesis of the plants. However, the sealing mode has the problems of long transportation distance, low efficiency and small scale, and can not meet the industrial large-scale sealing requirement under the current situation.

Disclosure of Invention

The invention mainly aims to provide a system and a method for sealing and storing carbon dioxide based on a coal mine goaf, and aims to solve at least one technical problem.

In order to achieve the purpose, the invention provides a system for sealing and storing carbon dioxide based on a coal mine goaf, wherein the coal mine goaf is positioned in a caving zone goaf, a fracture zone and a bending subsidence zone are sequentially formed above the caving zone goaf, and the system comprises:

a carbon dioxide temporary storage device;

the underground closed space is positioned in the caving zone and used for sealing and storing carbon dioxide, and the underground closed space is formed by surrounding a protective coal pillar, a well field boundary protective coal pillar and a closed roadway in the coal mine goaf;

the gas injection device comprises a gas injection pipeline communicated with the carbon dioxide temporary storage device, the gas injection pipeline sequentially penetrates through a bending subsidence zone and a crack zone and extends into the underground closed space;

and the monitoring device comprises a monitoring pipeline which penetrates through the bent subsidence zone and the crack zone and extends into the underground closed space.

In addition, the invention provides a method for sealing carbon dioxide based on a system for sealing carbon dioxide in a coal mine goaf, which comprises the following steps:

inspecting and creating the sealing condition of the coal mine goaf;

determining the positions of a gas injection hole and a monitoring hole;

according to the positions of the gas injection hole and the monitoring hole, a pipeline is arranged by drilling downwards from the ground surface above the underground closed space, and a carbon dioxide temporary storage device, a gas injection device and a monitoring device are installed and connected;

injecting carbon dioxide into the underground closed space.

In addition, the system for sealing and storing carbon dioxide based on the coal mine goaf can also have the following additional technical characteristics.

According to an embodiment of the invention, the gas injection device further comprises a pressure sensor and a concentration sensor arranged in the gas injection pipeline, the monitoring device further comprises a pressure sensor and a concentration sensor arranged in the monitoring pipeline, the system further comprises a controller connected with the pressure sensor and the concentration sensor, and a remote monitoring device connected with the controller.

According to an embodiment of the invention, the gas injection device further comprises power supply devices arranged on the gas injection device and the monitoring device, and the power supply devices are respectively connected with the pressure sensor and the concentration sensor.

According to one embodiment of the invention, at least two electrically controlled safety valves are arranged in the gas injection pipeline; at least two non-return safety valves are arranged in the monitoring pipeline.

According to one embodiment of the invention, the gas injection pipe is in communication with a central region of the underground enclosure and the monitoring pipe is in communication with a boundary region of the underground enclosure.

According to an embodiment of the present invention, the method further comprises the following steps of installing and connecting the carbon dioxide temporary storage device, the gas injection device and the monitoring device:

and cement mortar is poured between the outer walls of the gas injection pipeline and the monitoring pipeline and the rock stratum, so that the safety and reliability of the pipeline are enhanced.

According to one embodiment of the invention, before the step of injecting carbon dioxide into the underground enclosed space, the method further comprises:

and injecting air into the underground closed space until the underground closed space reaches a preset pressure value, monitoring the real-time pressure value of the underground closed space through a monitoring device, and determining whether the underground closed space meets the sealing condition or not according to the real-time pressure value and the preset pressure value.

According to an embodiment of the invention, determining whether the underground closed space meets the sealing condition according to the magnitude of the real-time pressure value and the preset pressure value comprises the following steps:

determining that the real-time pressure value is equal to a preset pressure value, and determining that the underground closed space meets the sealing condition; or

And determining that the real-time pressure value is smaller than a preset pressure value, determining that the underground closed space does not meet the sealing condition, carrying out geological exploration work, searching and determining the positions of the fault and the collapse column which are communicated with the earth surface, and then carrying out grouting plugging on the fault and the collapse column.

According to one embodiment of the invention, before the step of determining that the underground closed space meets the closed condition, the method further comprises the following steps: determining that the underground closed space region does not belong to a water resource enrichment region;

the step of determining that the underground enclosed space meets the enclosed conditions comprises:

determining that the caving zone and the fissure zone are not communicated with the ground surface;

determining the positions of a fault and a collapse column which are communicated with the ground surface, and grouting and plugging the fault and the collapse column;

and (5) reinforcing and sealing the closed roadway of the coal mine goaf.

Compared with the prior art, the invention has the following beneficial effects:

the invention provides a system and a method for sealing and storing carbon dioxide based on a coal mine goaf, which can economically, efficiently and massively seal and store a large amount of carbon dioxide, seal and store the carbon dioxide as a resource, and can be extracted and utilized again when necessary, thereby realizing convenient sealing and subsequent use of the carbon dioxide.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a coal mine goaf profile in one embodiment of the present invention;

FIG. 2 is a cross-sectional view of an underground enclosure in accordance with an embodiment of the present invention;

FIG. 3 is a schematic diagram of a system for sequestering carbon dioxide in a mined-out area in accordance with an embodiment of the invention;

FIG. 4 is a graph illustrating the distribution of openings in an underground enclosure in accordance with one embodiment of the present invention;

FIG. 5 is a schematic view showing the structure of a gas injection apparatus according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a monitoring device according to an embodiment of the present invention;

FIG. 7 is an enlarged view of a portion of FIG. 6;

FIG. 8 is a schematic illustration of a trapping column plugging in one embodiment of the present invention.

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are only for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "connected," "secured," and the like are to be construed broadly, and for example, "secured" may be a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In addition, the technical solutions in the embodiments of the present invention may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination of technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

Systems and methods for sequestration of carbon dioxide based on coal mine goafs in some embodiments of the present invention are described below with reference to fig. 1-8.

As shown in fig. 1 to 6, an embodiment of the present invention provides a system for sealing carbon dioxide in a coal mine goaf, where the coal mine goaf 10 is located in an caving zone 11, a fracture zone 12 and a curved subsidence zone 13 are sequentially formed above the caving zone 11, the system for sealing carbon dioxide in a coal mine goaf includes a carbon dioxide temporary storage device, at least one underground closed space 14, a gas injection device 15 and at least one monitoring device 16, where the underground closed space 14 is located in the caving zone 11 and is used for sealing carbon dioxide, the underground closed space 14 is surrounded by a coal pillar protection 101, a coal pillar protection 102 on a well field boundary, and a closed roadway 103 in the coal mine goaf 10, the gas injection device 15 includes a gas injection pipeline 150 communicated with the carbon dioxide temporary storage device and is used for injecting carbon dioxide in the carbon dioxide temporary storage device into the underground closed space 14, the gas injection pipeline 150 penetrates through the bending subsidence zone 13 and the fissure zone 12 in sequence and extends into the underground closed space 14, the monitoring device 16 is used for monitoring the concentration and the pressure of carbon dioxide sealed in the underground closed space 14, and the monitoring device 16 comprises a monitoring pipeline 160 which penetrates through the bending subsidence zone 13 and the fissure zone 12 and extends into the underground closed space 14.

Specifically, the temporary carbon dioxide storage device is arranged at a flat position on the periphery of a gas injection hole and mainly comprises a gas storage tank with pressure for automobile transportation (or a pressure gas storage tank constructed by underground concrete). The temporary storage device may store a plurality of kinds of carbon dioxide-rich tail gas discharged by industry (for example, carbon dioxide-rich tail gas discharged by industrial facilities such as a thermal power plant, a steel plant, a coal chemical industry and the like during operation), preferably power plant flue gas, carbon dioxide tail gas discharged by a coal chemical industry device or a mixed gas of the two, more preferably power plant flue gas, a mixed gas of power plant flue gas and carbon dioxide tail gas discharged by a coal chemical industry device, and most preferably power plant flue gas.

In an embodiment of the present invention, with reference to fig. 4, an air inlet 140 is formed in a middle region of the underground closed space 14, through holes 141 are respectively formed in two side edge regions of the underground closed space 14, an air injection pipe 150 is communicated with the air inlet 140, and a monitoring pipe 160 is communicated with the through holes 141.

It should be noted that, in a preferred embodiment, the at least one underground closed space 14 is a plurality of underground closed spaces, for example, 2 to 6 underground closed spaces, and the plurality of underground closed spaces may be injected with carbon dioxide simultaneously or alternately, so as to improve the treatment efficiency.

Further, in this embodiment, with continued reference to fig. 5-7, the gas injection apparatus 15 further includes a pressure sensor 151 and a concentration sensor 152 disposed in the gas injection pipe 150, the monitoring apparatus 16 further includes a pressure sensor 151 and a concentration sensor 152 disposed in the monitoring pipe 160, and the system for sequestering carbon dioxide in a coal mine goaf further includes a controller connected to the gas injection pipe 150, the pressure sensor 151 and the concentration sensor 152 in the monitoring pipe 160, and a remote monitoring device connected to the controller. In particular, the remote monitoring device may be a server, a cell phone, a computer, or other monitoring device for monitoring pressure and concentration values of carbon dioxide within the underground enclosure 14. The pressure sensor 151 and the concentration sensor 152 can acquire the pressure value and the concentration value of the carbon dioxide in the underground closed space 14, and transmit the pressure value and the concentration value of the carbon dioxide to the controller, and the controller transmits the pressure value and the concentration value of the carbon dioxide to the remote monitoring equipment, so that continuous monitoring and timed recording of the pressure value and the concentration value of the carbon dioxide are realized.

It should be noted that, with continued reference to fig. 5 to 7, the system for sealing and storing carbon dioxide in a coal mine goaf further includes a power supply device 17 disposed on the gas injection device 15 and the monitoring device 16, and the power supply device 17 is respectively connected to the gas injection pipeline 150, the pressure sensor 151 and the concentration sensor 152 in the monitoring pipeline 160, and the controller, and is configured to implement solar power supply.

It should be noted that the power supply device 17 may be solar energy, wind energy, or a power grid, and the embodiment is not limited herein.

In addition, with continued reference to fig. 5-7, at least two electronically controlled safety valves 153 are disposed in the gas injection pipe 150 at locations corresponding to the curved dip zone 13 and the fractured zone 12, and at least two check safety valves 161 are disposed in the monitoring pipe 160 at locations corresponding to the curved dip zone 13 and the fractured zone 12. Specifically, in order to prevent the carbon dioxide sealed in the underground enclosed space 14 from overflowing and ensure the absolute safety of the sealed carbon dioxide, in the present embodiment, two electrically controlled safety valves 153 and a non-return safety valve 161 are respectively disposed in the gas injection pipeline 150 and the monitoring pipeline 160 to prevent the sealed carbon dioxide from being ejected. Meanwhile, in consideration of the stability of the rock stratum structure, a double-layer electric control safety valve 153 and a double-layer check safety valve 161 are respectively arranged in the bent subsidence zone 13 and the fracture zone 12 to ensure compact and reliable sealing, the electric control safety valve 153 and the check safety valve 161 are independent pipeline sections respectively, and the lower pipeline of the drill hole is installed in the gas injection pipeline 150 and the monitoring pipeline 160 and is used as a part of the gas injection pipeline 150 and the monitoring pipeline 160 to be inserted into the hole along with the pipeline.

It should be noted that the installation positions of the electric control safety valve 153 and the check safety valve 161 in the present application are not limited to the positions corresponding to the curved subsidence zone 13 and the fractured zone 12, and the electric control safety valve 153 and the check safety valve 161 may be installed in the gas injection pipeline 150 and the monitoring pipeline 160. In this embodiment, a mounting bracket may be disposed in the gas injection pipe 150 and the monitoring pipe 160, and the mounting bracket may be used to fix the pressure sensor 151 and the concentration sensor 152, and fix a signal and power supply cable connected to the pressure sensor 151 and the concentration sensor 152 along the inner wall of the gas injection pipe 150 and the monitoring pipe 160, wherein the pressure sensor 151 and the concentration sensor 152 are located in the region of the gas injection pipe 150 and the monitoring pipe 160 corresponding to the fractured zone 12, and the pressure sensor 151 and the concentration sensor 152 are located below the electrically controlled safety valve 153 or the non-return safety valve 161.

Next, the method for sequestering carbon dioxide by using the system for sequestering carbon dioxide in a goaf of a coal mine in this embodiment is described in detail, and specifically includes the following steps:

s100, checking and creating the sealing condition of the coal mine goaf;

firstly, determining that the caving zone 11 and the fracture zone 12 are not communicated with the earth surface; specifically, a caving zone 11, a fissure zone 12 and a bending subsidence zone 13 (three zones for short) are formed after coal mining is finished, the fissure zone 12 is a main factor for destroying the sealing condition of the underground closed space, and the condition that whether the underground closed space 14 is closed or not is influenced by the fact that the caving zone 11 and the fissure zone 12 are not communicated with the ground surface;

the coal mine goaf fissure zone range calculation formula is as follows:largest primary H of underground coal mine_{Mining height}And 9m, substituting the formula and reserving a certain guarantee coefficient, and theoretically calculating to obtain the sealing condition of the coal mine goaf with the depth of 100 m. Most of coal in China is buried under 200 meters, so that a plurality of coal mines meeting the sealing condition can be seen.

Secondly, determining that the region of the underground closed space 14 does not belong to a water resource enrichment region; specifically, water resource enrichment areas such as riverways and lakes exist at the upper parts of individual coal mine goafs, and large and continuous water inflow is displayed during the coal production. The coal mine goaf is sealed and then is filled with a large amount of sewage, which is not suitable for being used as a carbon dioxide sealing zone and needs to be removed.

Thirdly, determining the positions of the fault and the collapse column 18 communicated with the ground surface, and performing grouting plugging on the fault and the collapse column 18; specifically, the fault and the collapse column 18 which are communicated with the ground surface can affect the sealing of the underground closed space, and in order to solve the problem, the embodiment surveys the geology, acquires the geological structure information, determines the position of the fault and the collapse column 18 which are communicated with the ground surface, and adopts a grouting method to seal, so that the full sealing is realized.

It should be noted that, the method for plugging the fault and the trapping column 18 is the same, and as shown in fig. 8, this embodiment describes in detail the plugging of the trapping column 18, and the method is as follows:

1. preparing a grouting material, and conveying the grouting material by using a slurry truck 19, wherein the slurry is uniformly stirred according to a certain proportion by using 32.5 common portland cement as a main material and a waterproof material and a pore sol agent as auxiliary materials;

2. engineering drilling is carried out at the bottom, middle and top positions of the collapse column 18 (aperture)) Arranging a grouting guide pipe 20;

3. and grouting is respectively carried out according to the sequence from bottom to top, so that the collapse column 18 is ensured to be sealed horizontally, and the safety factor is increased. And (3) conveying the slurry on the slurry vehicle 19 to a grouting guide pipeline 20 by using a grouting pump station 21, controlling the grouting pressure to be 2MPa each time, stopping grouting when the grouting pressure exceeds the pressure, calculating the grouting volume, and estimating the size of the closed space.

And finally, reinforcing and sealing the closed roadway 103 in the coal mine goaf. Specifically, although the sealing roadway 103 is sealed by masonry mortar, the sealing roadway is a weak point, and reinforcement and sealing are performed again to ensure that the underground sealed space is sealed.

S200: determining the positions of the gas injection hole 22 and the monitoring hole 23; in the embodiment, the positions of the gas injection holes 22 and the monitoring holes 23 can be determined according to the existing production-verified geological plan in the coal mining process;

s300: according to the positions of the gas injection hole 22 and the monitoring hole 23, a pipeline is arranged by drilling downwards from the ground surface above the underground closed space 14, and a carbon dioxide temporary storage device, a gas injection device 15 and a monitoring device 16 are installed and connected;

in the present embodiment, in combination with the diameter of the gas injection pipe 150, the gas injection hole 22 can be a 168mm conventional drilled hole diameter, and the gas injection pipe 150 can be a 100mm diameter alloy pipe to meet the requirements of gas injection amount and gas injection pressure. Grout is filled between the outer wall of the gas injection pipe 150 and the rock wall of the gas injection hole 22, so that the compaction and compression resistance of the pipeline are guaranteed, and the reliability and safety of the pipeline are enhanced.

Accordingly, in conjunction with the use of monitoring holes 23, monitoring holes 23 are selected to be 110mm conventional borehole diameters and monitoring tube 160 is selected to be 76mm diameter alloy tubing to meet monitoring and safety requirements. Grout is filled between the outer wall of the monitoring pipe 160 and the monitoring hole 23, so that the pipeline is guaranteed to be compact and pressure-resistant, and the reliability and safety of the pipeline are enhanced.

S400: performing a sealing test on the underground enclosed space 14;

injecting air into the underground closed space 14 until the underground closed space 14 reaches a preset pressure value, for example, 5MPa, monitoring the real-time pressure value of the underground closed space 14 through the monitoring device 16, continuously testing for 10 days, and determining whether the underground closed space 14 meets the sealing condition according to the real-time pressure value and the preset pressure value. Specifically, when the real-time pressure value is equal to the preset pressure value, it can be determined that the underground enclosed space 14 meets the sealing condition, the test is qualified, and the switch of the electric control safety valve 153 is opened to release the gas;

correspondingly, when the real-time pressure value is smaller than the preset pressure value, the underground closed space 14 is determined not to meet the sealing condition, the leakage pressure release position is searched and determined through geological survey again, and then grouting plugging is conducted on the leakage pressure release position.

S500: carbon dioxide is injected into the underground enclosure 14.

In this example, according to geological data of the production process, as shown in table 1, the temperature of the underground closed space 14 year round is 5 ℃ (based on the measured data), and the pressure required for carbon dioxide to become liquid in this case is 3.96 MPa. And (3) continuously injecting the carbon dioxide temporary storage device into the underground closed space 14 through a gas injection pipeline by using a pressure pump, and simultaneously monitoring the pressure value of the underground closed space 14 in real time to reach 3.96MPa, namely, filling the underground closed space 14.

TABLE 1 temperature and pressure comparison table for liquid carbon dioxide

Temperature of	Pressure of
		10	4.50
9	4.39
		8	4.28
7	4.18
		6	4.07
5	3.96
		4	3.87
3	3.77
		2	3.67
1	3.58
		0	3.48
-1	3.39
		-2	3.30
-3	3.22
		-4	3.13
-5	3.05
		-6	2.96
-7	2.88
		-8	2.80
-9	2.72
		-10	2.65

S600: the pressure and concentration values of carbon dioxide within the underground enclosure 14 continue to be monitored.

In this embodiment, the pressure value and the concentration value of the carbon dioxide are monitored in real time by the monitoring device 16, and the collected pressure value and the collected concentration value are sent to the monitoring device at regular time, so that the pressure value and the concentration value of the carbon dioxide are monitored in real time and reported at regular time.

When the carbon dioxide is required to be extracted and utilized in the future, the electronic control safety valve 153 is switched on to slowly open the gas injection hole and is connected to the carbon dioxide collecting tank on the ground surface, and then the extraction and utilization of the carbon dioxide can be realized.

The embodiments of the present disclosure have been described above. However, these examples are for illustrative purposes only and are not intended to limit the scope of the present disclosure. The scope of the disclosure is defined by the appended claims and equivalents thereof. Various alternatives and modifications can be devised by those skilled in the art without departing from the scope of the present disclosure, and such alternatives and modifications are intended to be within the scope of the present disclosure.