Continuous mining and continuous filling recovery section coal pillar mining method and system

Abstract

The invention discloses a continuous mining and continuous filling recovery section coal pillar mining method and system, and the method comprises the steps: determining the position of a coal pillar working face crossheading, and carrying out gob-side entry driving along the positions, close to goaf, of the two sides of a coal pillar; grouting and plugging the goaf before tunneling, and injecting a flame retardant; side filling roadway forming is conducted on the goaf through coal gangue, and a supporting system of a coal pillar working face crossheading is constructed; supporting a coal pillar working face crossheading; the section coal pillars are recovered by adopting a continuous mining and continuous filling process, and coal bodies are replaced by filling bodies, so that the whole coal pillar recovery-filling process is ensured to be smoothly carried out until all coal resources are recovered. According to the method, the coal recovery rate can be increased, the problems of spontaneous combustion danger and toxic and harmful gas over-limit caused by goaf air leakage are solved, the fire hazard caused by sparks generated when a fully-mechanized coal winning machine touches old roadway anchor rods in the roadway tunneling process is solved by injecting the flame retardant, waste coal gangue can be effectively utilized, the problems of environmental pollution and the like are avoided, green mining is achieved, and the method is suitable for large-scale popularization and application. The mine service life is prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of coal mining, and in particular relates to a method and system for mining coal pillars in a continuous mining, continuous filling and recovery section. Background Art

[0002] In the process of coal mining, in order to ensure the stability of the mining tunnel and meet the safety requirements such as ventilation and fire prevention, coal pillars of a certain size are usually left at the coal mining face, which are called "segmental coal pillars at the working face". These coal pillars are intentionally retained during coal mining and are not mined. In many coal producing areas in my country, the size of the segmental coal pillars is generally between 20 and 40 meters. In addition, a large amount of by-products such as coal gangue are also produced during the mining process.

[0003] However, the existing coal mining methods have some shortcomings. First, if these section coal pillars are not recovered, a large amount of coal resources will be wasted, reducing the mining efficiency and utilization rate of coal resources. Secondly, the accumulation of by-products such as coal gangue will not only occupy a large amount of land resources, but may also cause a series of environmental problems such as air pollution and water pollution, causing serious damage to the surrounding ecological environment. At the same time, when the goaf-side tunneling construction is carried out near the goaf on both sides of the coal pillars, there are many safety hazards due to the close proximity to the goaf. For example, air leakage in the goaf may cause spontaneous combustion of coal and produce excessive toxic and harmful gases, which seriously threatens the safe production of mines; during the tunnel excavation process, the multi-purpose excavator may also touch the anchor rods of the old tunnel, generating sparks, which in turn causes the risk of fire, further exacerbating the safety risks of the mine. Summary of the invention

[0004] In order to solve the above technical problems, the present invention proposes a method and system for continuous mining, continuous filling and recovery of coal pillars in the section to solve the problems existing in the above prior art.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a method for mining coal pillars in a continuous mining, continuous filling and recovery section, comprising:

[0006] Determine the location of the coal pillar working face drift, and dig lanes along the coal pillars near the goaf on both sides;

[0007] Before excavation, the goaf is sealed with grouting and flame retardant is injected;

[0008] The side of the goaf is filled with coal gangue to form a lane, and a support system for the coal pillar working face is constructed;

[0009] Support the coal pillar working face drift;

[0010] The continuous mining and filling process is adopted to recover the section coal pillar, and the coal body is replaced by the filling body, ensuring the smooth progress of the entire coal pillar mining-filling process until all coal resources are recovered.

[0011] Preferably, grouting and plugging the goaf includes:

[0012] During the excavation of the coal pillar working face, drill holes are arranged at the head of the tunnel near the goaf side and obliquely towards the goaf side;

[0013] Running casing through the borehole;

[0014] Through the casing, a filling pump is used to fill the pipeline to transport high-fluidity filling slurry to the caving area to fill the cracks in the caving zone of the goaf.

[0015] Preferably, the injected flame retardant comprises:

[0016] Use the method of dense shallow holes to arrange drilling holes at the head of excavation;

[0017] Through the drill hole, coal mine fire extinguishing agent slurry is injected into the crushed coal body in front of the head in proportion.

[0018] Preferably, the support system for constructing the coal pillar working face drift includes:

[0019] The filling bag is fixed by using supporting materials, wherein the supporting materials include a single support and an anchor rod;

[0020] Starting the filling pump to deliver the paste prepared from coal gangue into the filling bag through the filling pipeline;

[0021] As the paste is continuously injected, the filling bag is gradually filled, and when the paste solidifies, a wall structure is formed; the wall structure cooperates with the anchor support body to control the sinking of the roof and constitute a support system for the coal pillar working face chute.

[0022] Preferably, supporting the coal pillar working face drift includes:

[0023] Normal anchor net support is used on the solid coal side;

[0024] The top plate is reinforced with anchor nets and anchor cables;

[0025] For the side close to the goaf, backfill sidewalls, single bodies and articulated top beams are used for support.

[0026] Preferably, the continuous mining and filling process is used to recover the section coal pillar, including:

[0027] Several branch tunnels and coal pillar tunnels are arranged in the section coal pillar working face. Each branch tunnel and coal pillar tunnel uses a fully-mechanized excavator to dig and remove coal. Branch tunnels and coal pillar tunnels are left at intervals to support the roof. One tunnel is dug and the other is filled, and mining and filling are carried out in parallel.

[0028] Use backfill to protect the remaining coal pillars, and when the backfill forms support force, carry out secondary mining of the remaining coal pillars, and implement the non-collapse management method;

[0029] Divide the coal pillar working face of the section into multiple blocks for coordinated mining, and conduct retreat mining between the blocks;

[0030] After the mined branch tunnels are filled and the filling body is stable, the coal pillar tunnels are mined and filled from the inside to the outside until the entire coal pillar is mined and filled, thus realizing the full recovery of coal resources.

[0031] In a second aspect, the present invention provides a continuous mining and continuous filling recovery section coal pillar mining system, comprising:

[0032] The module of roadway driving along the goaf is used to determine the position of the coal pillar working face and to drive roadways along the goaf near the goaf on both sides of the coal pillar.

[0033] Goaf treatment module, used to grout and seal the goaf and inject flame retardant before excavation;

[0034] The support system construction module is used to fill the goaf side with coal gangue to form a lane and build a support system for the coal pillar working face.

[0035] The chute support module is used to support the chute of the coal pillar working face;

[0036] The coal recovery module is used to recover the section coal pillar by continuous mining and filling process. The coal body is replaced by the filling body to ensure the smooth progress of the entire coal pillar mining-filling process until all coal resources are recovered.

[0037] Compared with the prior art, the present invention has the following advantages and technical effects:

[0038] The present invention provides a method for mining coal pillars in a continuous mining and filling recovery section, comprising: first, determining the position of the coal pillar working face drift, and digging lanes along the goaf near the position of the goaf on both sides of the coal pillar; secondly, grouting and plugging the goaf and injecting flame retardant before excavation; then, filling the goaf side with coal gangue to form a lane, and constructing a support system for the coal pillar working face drift; further, supporting the coal pillar working face drift; finally, using the continuous mining and filling process to recover the section coal pillar, replacing the coal body with the filling body, to ensure the smooth progress of the entire coal pillar recovery-filling process until all coal resources are recovered.

[0039] The present invention improves the coal recovery rate by digging lanes along the goaf without coal pillars; by digging lanes along the goaf, the deformation of the lanes can be reduced, and the safety production conditions can be significantly improved. The present invention performs grouting to seal the goaf to achieve sealing of the goaf, and eliminate the risk of spontaneous combustion and excessive toxic and harmful gases caused by air leakage in the goaf. The present invention injects flame retardants during tunneling to solve the fire hazard caused by sparks generated by the fully-mechanized excavator touching the anchor rods of the old lane during tunneling. The present invention fills the goaf side with coal gangue to form a lane, which can effectively utilize abandoned coal gangue, avoid environmental pollution and other problems, achieve green mining, and extend the service life of the mine. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0041] Figure 1 It is a layout diagram of goaf-side roadway driving of coal pillars in the recovery section of an embodiment of the present invention;

[0042] Figure 2 This is a cross-sectional view of a roadway along a goaf in a coal pillar recovery section according to an embodiment of the present invention;

[0043] Figure 3 It is a schematic diagram of continuous mining and filling of coal pillars in the recovery section according to an embodiment of the present invention;

[0044] Among them, 1. The first goaf; 2. The second goaf; 3. The section coal pillar working face; 4. The first drift; 5. The filling body; 6. The anchor rod; 7. The monomer; 8. The anchor cable; 9. The second drift; 10. The cutting eye; 11. The block-section connecting lane; 12. The branch lane; 13. The coal pillar lane; 14. The first block section; 15. The second block section; 16. The third block section. DETAILED DESCRIPTION

[0045] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0046] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0047] Embodiment 1

[0048] like Figure 1-2 As shown, this embodiment provides a method for mining coal pillars in a continuous mining and continuous filling recovery section, comprising:

[0049] S1. Determine the position of the coal pillar working face slot, and dig lanes along the coal pillars near the goaf on both sides;

[0050] Specifically, in order to reduce the waste of resources, the coal pillar working face 3 between the first goaf 1 and the second goaf 2 of the working face is mined by using the continuous mining and filling process;

[0051] As an innovative implementation method, a first drift 4 of the coal pillar working face is excavated along the section coal pillar working face 3 close to the second goaf 2;

[0052] As an innovative implementation method, since the coal pillar is generally not wide, in order to recover the coal pillar to the greatest extent, the first drift 4 of the coal pillar working face adopts goaf-side excavation.

[0053] S2. Before excavation, grouting is performed to seal the goaf and inject flame retardant;

[0054] Furthermore, grouting and plugging of the goaf includes:

[0055] During the excavation of the coal pillar working face, drill holes are arranged at the head of the tunnel near the goaf side and obliquely towards the goaf side;

[0056] Running casing through the borehole;

[0057] Through the casing, a filling pump is used to fill the pipeline to transport high-fluidity filling slurry to the caving area to fill the cracks in the caving zone of the goaf.

[0058] Further, injecting the flame retardant comprises:

[0059] Use the method of dense shallow holes to arrange drilling holes at the head of excavation;

[0060] Through the drill hole, coal mine fire extinguishing agent slurry is injected into the crushed coal body in front of the head in proportion.

[0061] As an innovative implementation method, in order to solve the problems of spontaneous combustion caused by air leakage in the goaf of tunneling along the goaf and excessive toxic and harmful gases, grouting is performed in the goaf before tunneling to achieve sealing of the goaf. In order to solve the fire hazard caused by sparks generated by the multi-purpose excavator touching the anchor rods of the old tunnel during tunneling, flame retardants are injected to improve the flame retardant effect and fire prevention and extinguishing effect.

[0062] S3, fill the goaf side with coal gangue to form a lane, and build a support system for the coal pillar working face;

[0063] As an innovative implementation method, the support system for constructing the coal pillar working face drift includes:

[0064] The filling bag is fixed by using supporting materials, wherein the supporting materials include a single support and an anchor rod;

[0065] Starting the filling pump to deliver the paste prepared from coal gangue into the filling bag through the filling pipeline;

[0066] As the paste is continuously injected, the filling bag is gradually filled, and when the paste solidifies, a wall structure is formed; the wall structure cooperates with the anchor support body to control the sinking of the roof and constitute a support system for the coal pillar working face chute.

[0067] Specifically, the filling bag is fixed by the monomer pillars, anchor rods, etc., the filling body 5 is filled into the pipeline by the filling pump, the paste prepared from the gangue is pumped into the filling bag, and the filling body 5 forms a wall after solidification. The filling body 5, the anchor rod 6, the monomer 7, and the anchor cable 8 control the sinking of the roof and form the coal pillar working face channel support.

[0068] S4. Support the coal pillar working face drift;

[0069] Furthermore, the support of the coal pillar working face drift includes:

[0070] Normal anchor net support is used on the solid coal side;

[0071] The top plate is reinforced with anchor nets and anchor cables;

[0072] For the side close to the goaf, backfill sidewalls, single bodies and articulated top beams are used for support.

[0073] S5. Use continuous mining and filling technology to recover the section coal pillar, and replace the coal body with the filling body to ensure the smooth progress of the entire coal pillar mining-filling process until all coal resources are recovered.

[0074] As an innovative implementation method, the continuous mining and filling process is used to recover the section coal pillar, including:

[0075] Several branch tunnels and coal pillar tunnels are arranged in the section coal pillar working face. Each branch tunnel and coal pillar tunnel uses a fully-mechanized excavator to dig and remove coal. Branch tunnels and coal pillar tunnels are left at intervals to support the roof. One tunnel is dug and the other is filled, and mining and filling are carried out in parallel.

[0076] Use backfill to protect the remaining coal pillars, and when the backfill forms support force, carry out secondary mining of the remaining coal pillars, and implement the non-collapse management method;

[0077] Divide the coal pillar working face of the section into multiple blocks for coordinated mining, and conduct retreat mining between the blocks;

[0078] After the mined branch tunnels are filled and the filling body is stable, the coal pillar tunnels are mined and filled from the inside to the outside until the entire coal pillar is mined and filled, thus realizing the full recovery of coal resources.

[0079] Specifically, the first drift 4, the second drift 9 and the cut hole 10 of the section coal pillar working face constitute the working face production system; after the section coal pillar working face is out, the continuous mining and filling process is adopted for recycling. The recycling specifically includes:

[0080] (1) The block-section connecting tunnel 11 divides the coal pillar working face 3 into a plurality of blocks, which include: a first block section 14 , a second block section 15 , and a third block section 16 .

[0081] (2) Several branch tunnels 12 and coal pillar tunnels 13 are arranged in the block section of the coal pillar working face of the section. Each branch tunnel 12 and coal pillar tunnel 13 is excavated and coal is removed by a fully-mechanized excavator, and branch tunnels 12 are left at intervals to support the roof; one tunnel is excavated and the other is filled, and mining and filling are carried out in parallel.

[0082] (3) Use the backfill to protect the remaining coal pillar tunnel 13. When the backfill 5 forms a certain supporting force, carry out secondary mining of the remaining coal pillar tunnel 13 and implement the non-collapse management method.

[0083] (4) To ensure that the filling body 5 of the adjacent branch tunnel 12 has sufficient solidification time, the mining is reasonably coordinated between the blocks, that is, after the branch tunnel in the first block section 14 is completed, the branch tunnels in the second block section 15 and the third block section 16 are mined, and after the filling body in the branch tunnel 12 in the first block section 14 solidifies, the coal pillar tunnel 13 in the first block section 14 is mined again, etc., until the entire coal pillar is mined and filled, and all coal resources are recovered.

[0084] Embodiment 2

[0085] Based on the same inventive concept, this embodiment also provides a continuous mining and continuous filling recovery section coal pillar mining system, including:

[0086] The module of roadway driving along the goaf is used to determine the position of the coal pillar working face and to drive roadways along the goaf near the goaf on both sides of the coal pillar.

[0087] Goaf treatment module, used to grout and seal the goaf and inject flame retardant before excavation;

[0088] The support system construction module is used to fill the goaf side with coal gangue to form a lane and build a support system for the coal pillar working face.

[0089] The chute support module is used to support the chute of the coal pillar working face;

[0090] The coal recovery module is used to recover the section coal pillar by continuous mining and filling process. The coal body is replaced by the filling body to ensure the smooth progress of the entire coal pillar mining-filling process until all coal resources are recovered.

[0091] The continuous mining, continuous filling and recovery section coal pillar mining system provided in this embodiment has all the advantages of the continuous mining, continuous filling and recovery section coal pillar mining method provided in the first embodiment.

[0092] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for continuous mining and continuous filling recovery section coal pillar mining, characterized in that: The following steps are involved: Determine the location of the coal pillar working face drift, and dig lanes along the coal pillars near the goaf on both sides; Before excavation, the goaf is sealed with grouting and flame retardant is injected; The side of the goaf is filled with coal gangue to form a lane, and a support system for the coal pillar working face is constructed; Support the coal pillar working face drift; The continuous mining and filling process is adopted to recover the section coal pillar, and the coal body is replaced by the filling body, ensuring the smooth progress of the entire coal pillar mining-filling process until all coal resources are recovered.

2. The method according to claim 1, characterized in that Grouting and plugging of goaf includes: During the excavation of the coal pillar working face, drill holes are arranged at the head of the tunnel near the goaf side and obliquely towards the goaf side; Running casing through the borehole; Through the casing, a filling pump is used to fill the pipeline to transport high-fluidity filling slurry to the caving area to fill the cracks in the caving zone of the goaf.

3. The method according to claim 1, characterized in that Injected flame retardants include: Use the method of dense shallow holes to arrange drilling holes at the head of excavation; Through the drill hole, coal mine fire extinguishing agent slurry is injected into the crushed coal body in front of the head in proportion.

4. The method according to claim 1, characterized in that The support system for constructing the coal pillar working face drift includes: The filling bag is fixed by using supporting materials, wherein the supporting materials include a single support and an anchor rod; Starting the filling pump to deliver the paste prepared from coal gangue into the filling bag through the filling pipeline; As the paste is continuously injected, the filling bag is gradually filled, and when the paste solidifies, a wall structure is formed; the wall structure cooperates with the anchor support body to control the sinking of the roof and constitute a support system for the coal pillar working face chute.

5. The method according to claim 1, characterized in that Supporting the coal pillar working face includes: Normal anchor net support is used on the solid coal side; The top plate is reinforced with anchor nets and anchor cables; For the side close to the goaf, backfill sidewalls, single bodies and articulated top beams are used for support.

6. The method according to claim 1, characterized in that The coal pillars in the recovery section using the continuous mining and filling process include: Several branch tunnels and coal pillar tunnels are arranged in the section coal pillar working face. Each branch tunnel and coal pillar tunnel uses a fully-mechanized excavator to dig and remove coal. Branch tunnels and coal pillar tunnels are left at intervals to support the roof. One tunnel is dug and the other is filled, and mining and filling are carried out in parallel. Use backfill to protect the remaining coal pillars, and when the backfill forms support force, carry out secondary mining of the remaining coal pillars, and implement the non-collapse management method; Divide the coal pillar working face of the section into multiple blocks for coordinated mining, and conduct retreat mining between the blocks; After the mined branch tunnels are filled and the filling body is stable, the coal pillar tunnels are mined and filled from the inside to the outside until the entire coal pillar is mined and filled, thus realizing the full recovery of coal resources.

7. A continuous mining and continuous filling recovery section coal pillar mining system, characterized in that: include: The module of roadway driving along the goaf is used to determine the position of the coal pillar working face and to drive roadways along the goaf near the goaf on both sides of the coal pillar. Goaf treatment module, used to grout and seal the goaf and inject flame retardant before excavation; The support system construction module is used to fill the goaf side with coal gangue to form a lane and build a support system for the coal pillar working face. The chute support module is used to support the chute of the coal pillar working face; The coal recovery module is used to recover the section coal pillar by continuous mining and filling process. The coal body is replaced by the filling body to ensure the smooth progress of the entire coal pillar mining-filling process until all coal resources are recovered.

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