A method for storing carbon dioxide in goaf by cutting the roof into lanes

Abstract

The present invention relates to the technical field of coal mining, and in particular to a method for sealing carbon dioxide in a goaf of a roadway by cutting the top, wherein a roof pre-crack is performed by blasting in a certain range in front of a mining face to form a cut; a gangue support is arranged near the mining face for gangue support, and a grouting hole is drilled on the roof of the mining roadway after the gangue in the goaf is compacted and stabilized, and grouting is performed on the gangue of the remaining roadway to form a gangue filling wall to seal the goaf, and the gangue support is removed after solidification in the grouting area; after mining is completed, the main roadway protects the coal pillar, the boundary coal pillar and the gangue filling wall to form a closed space, and carbon dioxide is injected from the ground to the goaf of the upper mining face for sealing. The cost of carbon dioxide sealing can be greatly reduced, and since a large amount of carbon dioxide is injected into the goaf, the risk of spontaneous combustion of coal residues in the goaf and gas explosion in the goaf can also be greatly eliminated.

Description

Technical Field

[0001] The invention belongs to the technical field of coal mining, and in particular relates to a method for sealing carbon dioxide in a goaf area by cutting the roof into a lane. Background Art

[0002] After underground coal resources are mined, a large number of underground goafs will be left behind. These goafs not only cause geological disasters such as land collapse and surface subsidence, but also pose risks such as gas leakage and groundwater pollution. Carbon dioxide, as the main greenhouse gas, is increasingly causing global climate change due to its emission. Carbon dioxide storage in mine goafs refers to the technology of capturing carbon dioxide generated in the industrial production process and injecting it into closed underground goafs for permanent storage. On the one hand, this technology can effectively fill underground space, improve the stability of the overlying rock formations in the goafs, and reduce the possibility of geological disasters; on the other hand, it can permanently seal carbon dioxide, reduce its emission into the atmosphere, and slow down the trend of global warming.

[0003] The top-cutting, pressure-relieving, no-coal-pillar, self-forming lane technology can greatly improve the coal resource recovery rate of the working face because it eliminates the section coal pillars between adjacent working faces in traditional longwall mining. In addition, since this technology can automatically form lanes, it can also greatly alleviate the problem of tight mining and succession in the mine. However, the goafs after using the top-cutting, pressure-relieving, no-coal-pillar, self-forming lane technology have not been well utilized, especially when the goafs are filled with collapsed gangue after using the top-cutting lane technology, greatly reducing the overlying rock strata and surface settlement damage in the goafs. Using the goafs with top-cutting lanes to store carbon dioxide is an effective method, so it is necessary to study the method of carbon dioxide storage in the goafs with top-cutting lanes.

[0004] Therefore, it is necessary to provide an improved technical solution to address the above-mentioned deficiencies in the prior art. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned deficiencies in the prior art, and the present invention provides a method for sealing carbon dioxide in a goaf by cutting the roof into a lane.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A method for storing carbon dioxide in a goaf by cutting off the roof and forming a laneway comprises the following steps:

[0008] Step S1, excavating a mining tunnel at the side of the mining working face;

[0009] Step S2, supporting the surrounding rock of the mining tunnel at the excavation end;

[0010] Step S3, drilling pre-crack holes along the roof of the mining roadway close to the goaf within a certain range in front of the mining working face, and pre-crack the roof to form a cut by blasting;

[0011] Step S4, setting a rock retaining support at a position close to the mining working face for rock retaining support, and moving the rock retaining support as the mining working face advances;

[0012] Step S5, after the gangue in the goaf is compacted and stabilized, grouting holes are drilled on the roof of the mining tunnel, and the gangue in the remaining tunnel is grouted to form a gangue filling wall to block the goaf, and the gangue retaining support is removed after the grouting area solidifies;

[0013] Step S6, while the mining face is being mined, a lane is left along the goaf as the mining lane for the next mining face. After the mining of the next mining face is completed, the main lane protects the coal pillars, the boundary coal pillars and the gangue filling wall to form a closed space, and carbon dioxide is injected from the ground into the goaf of the previous mining face for sealing.

[0014] Preferably, the angle of the grouting hole is greater than the angle of the slit hole, and the elevation of the end of the grouting hole is greater than the top plate elevation by 1m;

[0015] The vertical angle between the slurry hole and the top plate of the retained entry: θ 注浆孔 =θ 切缝 +10;

[0016] Length of grouting hole: L 注浆孔 = .

[0017] Preferably, in step S2, holes are drilled in the roof and sides of the tunnel near the rear of the mining tunneling machine, and anchor rods, anchor cables, steel belts and metal meshes are installed to support the roof and sides of the mining tunnel to prevent roof collapse accidents caused by the large empty top distance at the excavation end of the mining tunnel.

[0018] Preferably, pre-splitting blasting is carried out outside 50 meters in front of the mining working face or after the tunnel excavation and support are completed.

[0019] Preferably, the spacing of the pre-splitting holes is designed according to the lithology within the range of the tunnel roof cut, and the depth of the drilling holes is based on the volume of the rock strata within the range of the cut that can completely fill the goaf after the collapse of the rock strata. 缝 =h 煤 / (Kp-1);

[0020] Among them, h 缝 is the height of the cut, h 煤 is the thickness of the coal seam at the working face, and Kp is the average expansion coefficient of the rock stratum within the cutting range of the goaf.

[0021] Preferably, a plurality of sealing holes for sealing carbon dioxide are drilled above the goaf area, a casing is provided in the sealing hole, a through hole is provided in the portion of the casing corresponding to the goaf, an air pressure pump is connected to the casing through a high-pressure pipe, and an input end of the air pressure pump is connected to a carbon dioxide gas source.

[0022] Preferably, a three-way valve is provided on the high-pressure pipe, and the three-way valve is correspondingly connected to the pulping equipment through a hydraulic pump.

[0023] Preferably, slurry is first supplied to the goaf through a hydraulic pump, and when the supply pressure reaches 40% of the preset pressure, the air pressure pump is switched to supply carbon dioxide through a three-way valve, and when the supply pressure reaches 90% of the preset pressure, the hydraulic pump is switched to supply slurry again through the three-way valve until the preset pressure is reached;

[0024] The pressure is maintained by a hydraulic pump, and after the slurry is fully solidified, the hydraulic pump and the air pump are removed to complete the carbon dioxide sealing.

[0025] Preferably, a portion of the casing corresponding to the top of the goaf is provided with a plurality of rods, and the plurality of rods radially extend into the casing so that the casing and the slurry are solidified into one as the slurry solidifies.

[0026] Beneficial effect: Compared with the traditional longwall mining abandoned mine carbon dioxide storage technology, the method of carbon dioxide storage in the goaf of the present invention can not only greatly reduce the carbon dioxide storage cost, but also because a large amount of carbon dioxide is injected into the goaf, it can also greatly eliminate the risk of spontaneous combustion of coal residues in the goaf and gas explosion in the goaf.

[0027] The top-cutting and pressure-relieving technology of forming lanes without coal pillars eliminates the section protection coal pillars. In addition, the top-cutting can increase the expansion coefficient of the collapsed gangue in the goaf. At this time, the collapsed gangue in the goaf can fill the goaf and support its overlying rock strata. The overlying rock strata in the goaf will undergo very small uniform settlement, and there will not be a large number of tensile cracks on the surface. In addition, this technology performs local grouting on the gangue side during the lane retention process, which can not only seal the goaf by solidifying the gangue through the solidification of the slurry, but also support the collapsed gangue in the goaf to prevent it from pouring into the goaf. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0029] Figure 1 A schematic diagram of a mining tunnel support in a specific embodiment provided by the present invention;

[0030] Figure 2 This is a schematic diagram of the development of the mining tunnel in the specific embodiment provided by the present invention;

[0031] Figure 3 A schematic diagram of working face mining in a specific embodiment provided by the present invention;

[0032] Figure 4 A schematic diagram of gangue grouting in a goaf area in a specific embodiment provided by the present invention;

[0033] Figure 5 This is a schematic diagram of carbon dioxide storage in goaf areas in a specific embodiment provided by the present invention.

[0034] In the figure: 1. Mining working face; 2. Recovery tunnel; 3. Solid coal seam; 4. Anchor rod; 5. Anchor cable; 6. W steel belt; 7. Cutting seam; 8. Boundary coal pillar; 9. Main tunnel protection coal pillar; 10. Gangue filling wall; 11. Grouting hole; 12. Goaf; 13. Casing. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0036] In the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention. The terms "connected" and "connected" used in the present invention should be understood in a broad sense. For example, they can be fixed connections or detachable connections; they can be directly connected or indirectly connected through intermediate components. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0037] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0038] The traditional longwall mining abandoned mine carbon dioxide storage technology also needs to perform grouting in the overlying rock strata of the goaf 12 to seal the overlying rock strata of the goaf 12 before carbon dioxide can be stored in the abandoned mine. This is because the traditional longwall mining technology needs to retain the section protection coal pillar, which will cause a large range of uneven settlement of the overlying rock strata of the goaf 12 of the traditional longwall mining, and will cause a large number of tensile cracks on the surface. When carbon dioxide is stored, it is also necessary to perform grouting in the overlying rock strata of the goaf 12 to seal the overlying rock strata of the goaf 12. In addition, since the coal pillars in the traditional longwall mining section are prone to stress concentration and large deformation, when carbon dioxide is stored in the goaf 12, it is also necessary to perform grouting on the coal pillars to seal the goaf 12 before carbon dioxide can be stored in the goaf 12.

[0039] The present invention provides a method for storing carbon dioxide in goaf areas by cutting the roof into lanes, such as Figure 1-5 As shown, the mine for carbon dioxide storage needs to reach a depth of 800m underground. The carbon dioxide stored underground can enter a supercritical state under the action of mine pressure. Therefore, in order to improve the safety of carbon dioxide storage, it is generally safer to seal carbon dioxide in the goaf 12 of a kilometer-deep well. The specific storage method includes the following steps: Step S1, excavating a recovery tunnel 2 on the side of the mining working face 1. During actual construction, the first working face in the mining area needs to excavate two recovery tunnels 2. With the completion of the mining of the first mining working face 1, the subsequent working faces only need to excavate one recovery tunnel 2;

[0040] Step S2, supporting the surrounding rock of the mining tunnel 2 at the excavation end, improving the stability of the surrounding rock of the mining tunnel 2 by installing anchor rods 4 and anchor cables 5, the anchor cables 5 are constant resistance anchor cables 5, and the anchor rods 4 and anchor cables 5 are staggered, thereby improving the deformation resistance of the tunnel surrounding rock (top plate and two sides).

[0041] Step S3, drill pre-crack holes along the roof of the mining tunnel 2 close to the goaf 12 within a certain range in front of the mining working face 1. Preferably, the pre-crack holes are drilled outside 50 meters in front of the working face, which is outside the range of influence of the advance support pressure. The roof is pre-cracked by blasting to form a cut 7, so that the gangue can collapse downward to fill the goaf 12.

[0042] Step S4, setting a rock retaining support near the mining working face 1 for rock retaining support. The rock retaining support is a specially customized rock retaining support, which is mainly used to support the top of the coal mine tunnel, the coal seam roof or the tunnel wall to prevent its collapse, so as to play a temporary rock retaining support role. As the overlying rock strata in the goaf 12 bends and sinks, the collapsed rock in the goaf 12 will be gradually compacted. When the collapsed rock in the goaf 12 behind the working face is compacted and stabilized (generally 200m behind the working face), the rock retaining support can be moved forward. Thus, during the mining process, the rock retaining support is moved as the mining working face 1 advances.

[0043] Preferably, the rock retaining support is an extended working face end support, and a rock retaining plate is installed on the side of the support goaf 12, which can be used as a temporary rock retaining support.

[0044] Step S5, after the collapsed gangue in the goaf 12 is compacted and stabilized (generally 200m behind the working face), a grouting hole 11 is drilled on the top plate of the mining tunnel 2. The grouting hole 11 is located on the side of the mining tunnel 2 close to the goaf 12. The gangue in the remaining tunnel is grouted through the grouting hole 11 to form a gangue filling wall 10 to seal the goaf 12. After the grouting area solidifies, the gangue retaining support is removed.

[0045] The local grouting sealing material of the gangue wall is a material that can solidify quickly, such as polymer materials, quick-setting concrete, etc. When the local grouting of the gangue wall solidifies, a wall composed of collapsed gangue and sealing materials can be formed. The wall can not only seal the goaf 12, but also has a certain strength to block the collapsed gangue in the goaf 12 and prevent it from pouring into the retained tunnel.

[0046] Step S6, while the mining face 1 is being mined, a lane is left along the goaf as the mining lane 2 for the next mining face 1. When the mining of the current face is completed, the lane-keeping work of the current face is also completed. After the mining of the next face is completed, that is, the lane-keeping is reused, after the mining of the next mining face 1 is completed, the main lane protection coal pillar 9, the boundary coal pillar 8 and the gangue wall form a closed space, and carbon dioxide is injected from the ground into the goaf 12 of the previous mining face 1 for sealing.

[0047] Since the top-cutting pressure-relieving and self-forming lane technology without coal pillars eliminates the section protection coal pillars, and the top-cutting can increase the expansion coefficient of the collapsed gangue in the goaf 12, the collapsed gangue in the empty area can fill the goaf 12 and support its overlying rock layer, and the overlying rock layer in the goaf 12 will undergo very small uniform settlement, and there will not be a large number of tensile cracks on the surface. In addition, this technology performs local grouting on the gangue side during the lane retention process, which can not only form a gangue filling body wall to block the goaf 12, but also support the collapsed gangue in the goaf 12 to prevent it from pouring into the goaf 12. Compared with the traditional carbon dioxide storage technology, the present invention can not only greatly reduce the carbon dioxide storage cost, but also greatly eliminate the risk of spontaneous combustion of coal residues in the goaf 12 and gas explosion in the goaf 12 because a large amount of carbon dioxide is injected into the goaf 12.

[0048] In this embodiment, during the process of injecting carbon dioxide from the ground, the pressure of carbon dioxide injected into the goaf 12 needs to be monitored in time, so as to timely find the leakage point of the carbon dioxide storage space in the goaf 12, and timely perform grouting to seal it. In addition, timely carbon dioxide sealing in the goaf 12 can also completely eliminate the spontaneous combustion of coal residues in the goaf 12 and gas exceeding the limit.

[0049] In an optional embodiment, the angle of the grouting hole 11 is greater than the angle of the slit hole 7, and the elevation of the end of the grouting hole 11 is greater than the elevation of the top plate by 1m; the angle between the grouting hole 11 and the top plate of the reserved lane in the vertical direction is: θ 注浆孔 =θ 切缝 +10;

[0050] Length of grouting hole: L 注浆孔 = .

[0051] In step S2, holes are drilled in the roof and two sides of the tunnel near the rear of the mining tunnel boring machine. As the tunnel boring machine advances forward, the anchor rod 4 / cable drill rig is used to drill holes in the roof and two sides of the tunnel in time behind the tunnel boring machine (drilling holes according to the positions in the support design plan of the mining tunnel 2), and then the anchor rod 4, anchor cable 5, steel belt and metal mesh are installed to support the roof and two sides of the mining tunnel 2. When installing the anchor cable 5, the anchor agent must be installed in the drill hole first, and then the steel strand must be installed in the drill hole. Then, according to the tunnel support design plan, the first row of anchor cables 5 on the front side of the tunnel are connected using the W steel belt 6 in the direction of the tunnel (the W steel belt 6 in the direction of the tunnel contains three anchor cable 5 holes, and one steel belt can connect three anchor cables 5 together when used), and finally the tray and lock are installed. In addition, the four rows of anchor cables 5 on the auxiliary side of the tunnel are connected using a W-steel belt 6 in the inclination direction of the tunnel (the W-steel belt 6 in the inclination direction of the tunnel contains two anchor cable 5 holes, and when in use, one steel belt can only connect two anchor cables 5 together).

[0052] In this embodiment, the anchor rods 4 located on both sides of the tunnel are grouting anchor rods 4, and no anchor cables 5 are set on the side of the mining tunnel 2 close to the goaf 12. In step S5, grouting is simultaneously performed on the side close to the goaf 12 to form a complete slurry consolidation wall on the side of the mining tunnel 2.

[0053] Furthermore, in step S2, a plurality of vertical W steel belts 6 are perpendicular to the direction of the tunnel and are located on the side of the roof away from the goaf 12, and a plurality of forward W steel belts 6 are distributed at intervals along the direction of the tunnel, and the forward W steel belts 6 are located on the side of the pre-crack hole away from the goaf 12, thereby protecting the roof and preventing pre-crack damage to the roof.

[0054] In an optional embodiment, pre-splitting blasting is performed outside the range of 50 meters in front of the mining working face 1 or after the tunnel excavation support is completed. No matter which stage the blasting is performed, it is only necessary to perform construction outside the range of 50 meters in front of the working face (outside the range of the advanced support pressure influence zone). Before the pre-splitting blasting, pre-splitting holes are designed on one side of the roof of the mining tunnel 2 close to the goaf 12. The spacing of the pre-splitting holes is designed according to the lithology within the range of the tunnel roof cut 7. The depth of the drilling hole is based on the volume of the broken expansion after the rock layer within the range of the cut 7 collapses, which can completely fill the goaf 12. 缝 =h 煤 / (Kp-1); where h 缝 is the height of the cut 7, h 煤 is the thickness of the coal seam at the working face, and Kp is the average expansion coefficient of the rock strata within the range of the cutting seam 7 in the goaf 12.

[0055] Using low-charge uncoupled charging method, each charging hole is both a blasting hole and a guide hole for adjacent blasting holes. After the explosives explode, concentrated stress is generated on each guide hole, forming a tensile crack along the direction of the blast hole connection line, and extending into a flat, through pre-crack. To ensure the shock absorption effect, the pre-crack hole must be detonated ahead of the main blast hole, and the advance should be at least 100ms. However, in places with high water content or soft rocks, in order to prevent the pre-crack from being filled, the pre-crack hole can be detonated 50~100ms in advance. The pre-crack hole and the drill hole are on the same plane, and the bottom of the pre-crack hole falls on a line with a deviation of no more than 5cm.

[0056] In an optional embodiment, a plurality of sealing holes for sealing carbon dioxide are drilled above the goaf 12. The sealing holes are set according to the area of ​​the goaf 12, and the sealing holes are drilled downward and arranged in the goaf 12. A casing 13 is provided in the sealing hole. The casing 13 is preferably a metal pipe or a PVC pipe. A through hole is provided in the portion of the casing 13 corresponding to the goaf 12. The through hole is used to allow carbon dioxide and slurry to enter the goaf 12. An air pressure pump is connected to the casing 13 through a high-pressure pipe, and the input end of the air pressure pump is connected to a carbon dioxide gas source. In the actual sealing process, grouting and carbon dioxide are alternately supplied, which can improve the stability of the goaf 12 on the one hand, and open up the channel of the goaf 12 through the slurry on the other hand to ensure the uniformity of the distribution of carbon dioxide.

[0057] Specifically, a three-way valve is provided on the high-pressure pipe, and the three-way valve is connected to the pulping equipment via a hydraulic pump. The slurry ratio is not limited here, and a pressure gauge is also provided on the high-pressure pipe.

[0058] In an optional embodiment, slurry is first supplied to the goaf 12 through a hydraulic pump. When the supply pressure reaches 40% of the preset pressure, the air pressure pump is switched to supply carbon dioxide through a three-way valve. The slurry can be evenly infiltrated in the goaf 12 driven by carbon dioxide, thereby ensuring the uniformity of the slurry. At the same time, the permeation channel of the goaf 12 can be opened up under the action of the slurry. When the carbon dioxide supply pressure reaches 90% of the preset pressure, the hydraulic pump is switched again through the three-way valve to supply slurry until the preset pressure is reached. The slurry is used to seal the sealing hole, and the pressure is maintained by the hydraulic pump. After the slurry is fully solidified, the hydraulic pump and the air pressure pump are removed to complete the carbon dioxide sealing.

[0059] In an optional embodiment, the portion of the casing 13 corresponding to the top of the goaf 12 is provided with a plurality of rods, which extend radially into the casing 13. The rods may be studs, which are threadedly assembled on the side wall of the casing 13. Thus, as the slurry solidifies, the casing 13 and the slurry are solidified into one, thereby improving the consolidation capacity of the slurry and the casing 13, and then ensuring the sealing performance after sealing.

[0060] Furthermore, the outer wall of the casing 13 is provided with at least one guide groove extending to the top of the goaf 12, the lower end of the guide groove extends to the bottom of the casing 13, and the upper end of the guide groove is not lower than 10m above the elevation of the upper edge of the goaf 12. A plurality of anti-slip protrusions are provided on the outer wall of the casing 13. The anti-slip protrusions can be wedge-shaped, or the anti-slip protrusions can be plug-in rods. The plug-in rods pass through the casing 13, one end of which extends out of the outer wall of the casing 13 by a certain length, and the other end extends into the casing 13; at least one sealing rubber ring is provided on the upper part of the casing 13 corresponding to the guide groove.

[0061] In this embodiment, the guide groove is a strip extending along the busbar of the casing 13, and seepage holes corresponding to the guide groove are provided on the side wall of the casing 13, so that the slurry can be distributed between the casing 13 and the sealing hole from the seepage holes, thereby ensuring the sealing performance. In another embodiment, the guide groove is a spiral structure extending along the casing 13.

[0062] In this embodiment, the anti-slip protrusion is located in the guide groove, and the bottom of the casing 13 extends to below the elevation of the lower edge of the goaf 12.

[0063] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are within the scope of protection of the pending claims of the present invention.

Claims

1. A method for storing carbon dioxide in goaf by cutting the top into lanes, characterized in that: The following steps are involved: Step S1, excavating a mining tunnel at the side of the mining working face; Step S2, supporting the surrounding rock of the mining tunnel at the excavation end; Step S3, drilling pre-crack holes along the roof of the mining roadway close to the goaf within a certain range in front of the mining working face, and pre-crack the roof to form a cut by blasting; Step S4, setting a rock retaining support at a position close to the mining working face for rock retaining support, and moving the rock retaining support as the mining working face advances; Step S5, after the gangue in the goaf is compacted and stabilized, a grouting hole is drilled on the roof of the mining tunnel, and the gangue in the remaining tunnel is grouted to form a gangue filling wall to block the goaf, and the gangue retaining support is removed after the grouting area solidifies; the grouting hole is located on the side of the mining tunnel close to the goaf, and the gangue in the remaining tunnel is grouted through the grouting hole to form a gangue filling wall to block the goaf, and the gangue retaining support is removed after the grouting area solidifies; The angle of the grouting hole is greater than that of the slit hole, and the elevation of the end of the grouting hole is 1m higher than the top plate elevation; The vertical angle between the grouting hole and the top plate of the reserved roadway: θ 注浆孔 =θ 切缝 +10; Length of grouting hole: L 注浆孔 = ; Step S6, while the mining face is being mined, a gob is left along the gob as the mining gob for the next mining face, after the next mining face is mined, the main gob is protected by coal pillars, boundary coal pillars and a gangue filling wall is formed into a closed space, and carbon dioxide is injected from the ground into the gob area of ​​the previous mining face for sealing; A plurality of sealing holes for carbon dioxide sealing are drilled above the goaf area, a casing is provided in the sealing hole, a through hole is provided in the portion of the casing corresponding to the goaf area, an air pressure pump is connected to the casing through a high-pressure pipe, and an input end of the air pressure pump is connected to a carbon dioxide gas source; The high-pressure pipe is provided with a three-way valve, and the three-way valve is correspondingly connected to the pulping equipment through a hydraulic pump; First, the slurry is supplied to the goaf through the hydraulic pump. When the supply pressure reaches 40% of the preset pressure, the air pressure pump is switched to supply carbon dioxide through the three-way valve. When the supply pressure reaches 90% of the preset pressure, the hydraulic pump is switched again through the three-way valve to supply the slurry until the preset pressure is reached. The hydraulic pump is used to maintain the pressure, and after the slurry is fully solidified, the hydraulic pump and the air pressure pump are removed to complete the carbon dioxide sealing; The portion of the casing corresponding to the upper portion of the goaf is provided with a plurality of insertion rods, and the plurality of insertion rods extend radially into the casing so that the casing and the slurry are solidified into one as the slurry solidifies; The outer wall of the casing is provided with at least one guide groove extending to the top of the goaf, the lower end of the guide groove extends to the bottom of the casing, and a plurality of anti-slip protrusions are provided on the outer wall of the casing; The anti-slip protrusion is an insertion rod, one end of which extends out of the outer wall of the casing for a certain length, and the other end extends into the casing; at least one sealing rubber ring is provided on the upper part of the casing corresponding to the guide groove; seepage holes corresponding to the guide groove are provided on the side wall of the casing, so that the slurry can spread from the seepage holes to the space between the casing and the sealing hole.

2. The method for storing carbon dioxide in goaf by cutting the top into lanes according to claim 1 is characterized in that: In step S2, holes are drilled in the roof and sides of the tunnel near the rear of the mining tunnel boring machine, and anchor rods, anchor cables, steel belts and metal mesh are installed to support the roof and sides of the mining tunnel to prevent the occurrence of roof collapse accidents caused by the large empty top distance at the excavation end of the mining tunnel.

3. The method for storing carbon dioxide in goaf by cutting the top into lanes according to claim 2 is characterized in that: Pre-splitting blasting is carried out outside 50 meters in front of the mining working face or after the tunnel excavation and support are completed.

4. The method for storing carbon dioxide in goaf by cutting the top into lanes according to claim 1 is characterized in that: The spacing of the pre-crack holes is designed according to the lithology within the range of the tunnel roof cut, and the depth of the drill hole is based on the volume of the rock stratum within the cut range after collapse to completely fill the goaf. 缝 =h 煤 / (Kp-1); Among them, h 缝 is the height of the cut, h 煤 is the thickness of the coal seam at the working face, and Kp is the average expansion coefficient of the rock stratum within the cutting range of the goaf.

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