Method for processing goaf of mechanized mining working face of vertical groove coal

Abstract

The invention relates to the technical field of coal mining, in particular to a method for processing a goaf of a mechanized mining working face of vertical channel coal, which is used for filling the goaf formed by downward mining along the inclined direction of a coal seam. Support is formed above the vertical groove coal working face through the hydraulic supports, after the hydraulic supports move, the areas, prone to liquid leakage, of the gaps between the hydraulic supports and the coal seam top and bottom plates and the gaps between the supports are blocked, then retaining walls are formed through baffles of an air return crossheading well and a material conveying crossheading well, and then the positions above the hydraulic supports are blocked by filling foam materials. And finally, cementing materials are injected into the goaf to be filled through high-position filling equipment, filling is completed, a filling area is formed, when the grouting filling height above the hydraulic support reaches 50-100 m, top cutting and bottom cutting operation is conducted above the coal face, a damage area and a crack area are formed, the damage area and the crack area are filled with the high-strength cementing materials, and the goaf to be filled is filled with the high-strength cementing materials. A self-stabilizing wall base structure is formed at the cut-off position of the top plate and the bottom plate, and good safety guarantee is provided for mining of vertical groove coal.

Description

Technical Field

[0001] This invention relates to the field of coal mining technology, and is a method for treating the goaf in a mechanized coal mining face. Background Technology

[0002] The goaf in a coal mining face is located above the coal mining face. The gangue that collapses from the goaf can cause great impact on the coal mining face and hydraulic supports. Common methods for filling the goaf in a coal mining face include dry filling, paste filling, high-moisture material filling, cemented filling, and step-by-step filling.

[0003] Chinese patent document CN120520578A discloses a method and system for backfilling and mining a steeply inclined, near-vertical, extra-thick coal seam, comprising the following steps: dividing the near-vertical, extra-thick coal seam into different mining levels of 20-40m; arranging a low-level mining system at the horizontal level of the boundary between the current and lower sections; arranging a high-level backfilling system within the roof or floor rock pillar at the horizontal level of the boundary between the current and upper sections; mining the coal seam in the current section using fully mechanized longwall mining; laying isolation nets and grout-blocking cloth in the goaf area using a net-laying and grout-blocking support as the coal face advances; using a high-suspension cavity space detection and characterization robot arranged in the high-level backfilling system to explore the goaf space; dividing the near-vertical, extra-thick coal seam into different sections for segmented mining; and performing in-situ grouting and backfilling of the subsequent mining space during the mining process to form a stable backfilling interface in the goaf area.

[0004] Chinese patent document CN120291874A discloses a green mining method for preventing and controlling disasters in near-vertical extra-thick coal seams by backfilling, including the following steps: dividing the near-vertical extra-thick coal seam into different sections with a thickness of 20-40m; mining each section by fully mechanized top coal caving; after the coal face advances 8-10m, i.e., one mining-backfilling step, setting up grout-blocking cloth on the hydraulic support for top coal caving backfilling mining and laying isolation nets in the goaf; grouting backfilling the goaf through a high-level process roadway; dividing the near-vertical coal seam into multiple horizontal sections and adopting a downward mining sequence to coordinate with timely backfilling of the goaf.

[0005] Currently, these goaf filling methods are only applicable to situations where the goaf is located behind the coal face, and cannot be applied to mechanized mining technology for vertical coal seam mining and goaf filling above the working face after mining. Summary of the Invention

[0006] This invention provides a method for treating the goaf in a mechanized mining face of vertical coal seam, which overcomes the shortcomings of the prior art. It can effectively solve the problem that existing goaf filling methods cannot be applied to the mechanized mining technology of vertical coal seam mining and the filling of the goaf above the working face after mining.

[0007] The technical solution of this invention is achieved through the following measures: a method for treating the goaf in a mechanized coal mining face, which involves filling the goaf formed by mining along the dip direction of the coal seam, including the following steps: S1. Hydraulic supports are used to form a support above the vertical coal mining face; S2. After the vertical coal mining face has been mined downwards for a predetermined distance, sealing material is filled above the hydraulic support to form a sealed area; S3. Use cementing materials to pour and form a filling area in the goaf above the hydraulic support; S4. Every 50 to 100 meters of filling, a layer of rock pillars shall be set in the goaf.

[0008] The following are further optimizations and / or improvements to the above-mentioned technical solution: The coal seam mentioned above is a steeply inclined coal seam with a dip angle of 60° to 90°. The width of the vertical coal mining face in the strike direction is 200m to 300m, and the length of the vertical coal mining face in the dip direction is 200m to 500m. Low-level reserved holes, high-level reserved holes, exhaust reserved holes and overflow reserved holes are set at intervals on the hydraulic support.

[0009] In step S2 above, filling the area above the hydraulic support with sealing material to form a sealing zone includes: S21, seal the gaps between the hydraulic supports below the goaf and the top and bottom plates of the coal seam, as well as the gaps between the hydraulic supports; S22, the goaf between the baffles of the return air roadway and the material transport roadway is sealed off; S23, fill the hydraulic support with sealing material to form a sealing area.

[0010] The above step S23 includes: S231, installing the first filling device on the vertical coal mining face; S232, every 4 to 10 hydraulic supports, a low-level filling pipe, a high-level filling pipe, an exhaust pipe and an overflow pipe are installed in the low-level reserved hole, the high-level reserved hole, the exhaust reserved hole and the overflow reserved hole respectively. The first end of the low-level filling pipe and the first end of the high-level filling pipe are both located above the hydraulic support. S233, connect the second end of the low-level filling pipe to the outlet of the first filling device; S234, The first filling equipment prepares the sealing material; S235, the first filling device fills the sealing material through the low-level filling pipe to the top of the hydraulic support to form a sealing area.

[0011] In step S212 above, the first end of the low-position filling pipe is located 0.2m to 0.5m above the highest point of the hydraulic support.

[0012] In step S212 above, the first end of the high-level filling pipe is not lower than the highest point of the goaf.

[0013] Step S3 above includes: S31, Install the second filling device on the ground; S32, connect the second end of the high-level filling pipe to the outlet of the second filling equipment; S33, The second filling equipment prepares the cementing material; S34, the second filling device fills the goaf above the sealing area with cementing material through the high-level filling pipe to form a filling area.

[0014] Step S4 above includes: S41, every 50 to 100m of backfilling, roof cutting and bottom cutting operations are carried out above the coal mining face, and damage zones and fracture zones are formed on both sides of the goaf; S42, the second filling equipment prepares high-strength cementing material, and fills the high-strength cementing material into the damaged area and fissure area on both sides of the goaf through the high-level filling pipe to form rock pillars, the height of which is 6 to 10 meters.

[0015] Compared with existing vertical coal mining technology, the present invention has the following advantages: (1) By arranging the roadway shafts along the dip direction of the coal seam, the first submerged mining was achieved in the vertical coal face; (2) Using self-developed hydraulic supports, it can adapt to the changes in the dip angle of vertical coal seams with an inclination angle of 60-90° and the mining of coal seams with different thicknesses of 4-10m; (3) The coal transportation of the working face is improved by replacing the traditional belt conveyor, scraper conveyor and self-flowing equipment with coal chutes arranged at a depth of more than 100m in the working face. (4) By using the working face equipment arrangement of coal mining machine + shuttle car + hydraulic support, continuous and efficient mechanized coal mining of vertical coal face can be achieved. Attached Figure Description

[0016] Appendix Figure 1 This is a schematic diagram of the front cross-sectional structure of the preferred embodiment of the present invention.

[0017] Appendix Figure 2 This is a side sectional view of the preferred embodiment of the present invention.

[0018] Appendix Figure 3 For the appendix Figure 2 A magnified structural diagram of point A in the middle.

[0019] The codes in the attached diagram are as follows: 1 is the main shaft, 2 is the auxiliary shaft, 3 is the ventilation shaft, 4 is the return air main roadway, 5 is the return air roadway, 6 is the material transport roadway, 7 is the hydraulic support, 8 is the sealing area, 9 is the filling area, 10 is the rock pillar, 11 is the roof, 12 is the floor, 13 is the first filling device, 14 is the low-level filling pipe, 15 is the high-level filling pipe, 16 is the exhaust pipe, 17 is the overflow pipe, 18 is the second filling device, and α is the inclination angle. Detailed Implementation

[0020] The present invention is not limited to the following embodiments, and the specific implementation can be determined according to the technical solution of the present invention and the actual situation.

[0021] In this invention, for ease of description, the description of the relative positions of the components is based on the appendix to the specification. Figure 1 The layout is described using a diagrammatic method, such as the positional relationships of front, back, top, bottom, left, and right, which are based on the instructions attached. Figure 1 The orientation of the layout is determined by the direction of the map.

[0022] The present invention will be further described below with reference to embodiments and accompanying drawings: Example 1: As shown in the attached document Figure 1 , 2 As shown in Figure 3, the method for treating the goaf in a vertical coal mechanized mining face involves filling the goaf formed by submerging along the diagonal direction of the coal seam, including the following steps: S1. Hydraulic support 7 is used to form a support above the vertical coal mining face; S2. After the vertical coal mining face has been mined downwards for a predetermined distance, sealing material is filled above the hydraulic support 7 to form a sealing zone 8. S3. The goaf above the hydraulic support 7 is filled with cementing material to form the filling area 9. S4. For every 50 to 100 m of filling, set 10 rock pillars on both sides of the goaf.

[0023] The vertical coal mining roadway system includes a main shaft 1, an auxiliary shaft 2, a ventilation shaft 3, and a return air roadway 4. Return air roadways 5 and material transport roadways 6 are also located on both sides of the vertical coal mining face. Because the vertical coal mining face is arranged along the dip direction of the coal seam, and the working face transport roadway and working face return air roadway are also arranged along the dip direction of the coal seam with a large inclination angle, this application names the working face transport roadway as material transport roadway 6 and the working face return air roadway as return air roadway 5. A high-level filling device is installed on the ground to transport cementing material to the goaf for filling. A low-level filling device is installed on the vertical coal mining face, using foam material as the sealing material. The low-level filling device is used to seal areas prone to leakage, such as the gaps between the hydraulic support 7 and the coal seam roof 11 and floor 12, and the gaps between the supports. It also acts as a buffer. The preset distance is 15 to 30 meters. The hydraulic support 7 can be based on existing known technology.

[0024] This application utilizes hydraulic supports 7 to form a support above the vertical coal face. After the hydraulic supports 7 move 15 to 30 meters with the vertical coal face, grouting is performed on the goaf area above the hydraulic supports 7 to be filled. During the grouting process, the areas prone to leakage, such as the gaps between the hydraulic supports 7 and the roof and floor 12 of the coal seam, and the gaps between the supports, are first sealed. Then, retaining walls are formed using the baffles of the return air shaft 5 and the material conveying shaft 6. Next, foam material is filled using low-level filling equipment to seal the area above the hydraulic supports 7. Finally, cementing material is injected into the goaf area using high-level filling equipment to complete the filling and form the filling area 9. The goaf treatment method for mechanized vertical coal mining faces provided by this application is convenient to construct. Rock pillars 10 are set on both sides of the goaf to enhance the adhesion between the goaf filling body and the roof and floor of the vertical coal face, providing a good safety guarantee for the mining of vertical coal.

[0025] The above-mentioned methods for handling the goaf in mechanized coal mining faces can be further optimized and / or improved according to actual needs: Example 2: As an optimization of the above examples, as shown in the appendix. Figure 1 , 2 As shown in Figure 3, the coal seam is a steeply inclined coal seam with an dip angle α of 60° to 90°. The width of the vertical trench coal mining face in the strike direction is 200m to 300m, and the length of the vertical trench coal mining face in the dip direction is 200m to 500m. Low-level reserved holes, high-level reserved holes, exhaust reserved holes and overflow reserved holes are set at intervals on the hydraulic support 7.

[0026] Low-level reserved holes, high-level reserved holes, vent reserved holes, and overflow reserved holes are provided at intervals on the hydraulic support 7. There are two vent reserved holes and two overflow reserved holes. The low-level reserved holes, high-level reserved holes, vent reserved holes, and overflow reserved holes are all equipped with existing known sealing mechanisms, such as valves or openable and closable covers. The setting of low-level reserved holes, high-level reserved holes, vent reserved holes, and overflow reserved holes facilitates the connection of filling pipelines to filling equipment during filling, making it convenient to carry out filling operations on the goaf above the hydraulic support 7.

[0027] Example 3: As an optimization of the above examples, as shown in the appendix. Figure 1 , 2 As shown in Figure 3, in step S2, sealing material is filled above the hydraulic support 7 to form a sealing area 8, including: S21, seal the gaps between the hydraulic support 7 below the goaf and the coal seam roof 11 and floor 12, as well as the gaps between the hydraulic supports 7; S22, the goaf between the baffles of the return air roadway 5 and the material transport roadway 6 is sealed off; S23, fill the sealing material above the hydraulic support 7 to form a sealing area 8.

[0028] By using the baffles of the return air roadway 5 and the material transport roadway 6 to form a retaining wall, leakage of sealing material can be avoided when filling the goaf between the baffles of the return air roadway 5 and the material transport roadway 6, thereby improving construction efficiency and reducing construction costs.

[0029] Example 4: As an optimization of the above examples, as shown in the appendix. Figure 1 , 2 As shown in Figure 3, step S23 includes: S231, installing the first filling device 13 on the vertical coal mining face; S232, every 4 to 10 hydraulic supports 7, a low-level filling pipe 14, a high-level filling pipe 15, an exhaust pipe 16 and an overflow pipe 17 are installed in the low-level reserved hole, the high-level reserved hole, the exhaust reserved hole and the overflow reserved hole respectively. The first end of the low-level filling pipe 14 and the first end of the high-level filling pipe 15 are both located above the hydraulic support 7. S233, connect the second end of the low-level filling pipe 14 to the outlet of the first filling device 13; S234, the first filling device 13 prepares a sealing material, wherein the sealing material is a foam material; S235, the first filling device 13 fills the sealing material through the low-level filling pipe 14 to the top of the hydraulic support 7 to form a sealing area 8.

[0030] Since personnel cannot enter the goaf area of ​​the vertical coal mining face, in order to improve the efficiency of goaf filling, low-level filling pipes 14, high-level filling pipes 15, exhaust pipes 16, and overflow pipes 17 are installed every 4 to 10 hydraulic supports 7, respectively, in the low-level reserved holes, high-level reserved holes, exhaust reserved holes, and overflow reserved holes. There are two exhaust pipes 16 and two overflow pipes 17. One exhaust pipe 16 and one overflow pipe 17 correspond to the low-level filling pipe 14, and the other exhausts... Pipe 16 and overflow pipe 17 correspond to the high-level filling pipe 15. In this way, the filling pipeline is pre-installed in the reserved hole on the hydraulic support 7, which saves the cost of filling roadway and filling borehole leading to the goaf. At the same time as laying the filling pipeline, exhaust pipe 16 and overflow pipe 17 are laid in the goaf to be filled through return air roadway 5 and below hydraulic support 7. When slurry comes out of overflow pipe 17, it means that the goaf has been filled. After the slurry comes out of overflow pipe 17, overflow pipe 17 is sealed in the well.

[0031] The filling material is a known foam material, such as the filling material for treating karst ground collapse described in Chinese patent document CN104446208B, or the cement foam filling material or fly ash foam filling material described in the article "Performance of Coal-based Solid Waste Foam Filling Material and Control of Surrounding Rock in Empty Lane Group" published by Sun Qiang et al. in Coal Science and Technology. The first filling device 13 is a known technology. The first filling device 13 includes a mixer and a filling pump connected together. The second end of the low-level filling pipe 14 is connected to the outlet of the filling pump. The first filling device 13 prepares the sealing material and mixes the sealing material evenly. The sealing material forms a sealing area 8 above the hydraulic support 7, which is used to seal the gaps between the hydraulic support 7 and the top and bottom plates 12 of the coal seam, as well as the gaps between the hydraulic supports 7 and the areas prone to leakage. It can also buffer the hydraulic support 7.

[0032] Example 5: As an optimization of the above examples, as shown in the appendix. Figure 2 , 3 As shown, in step S212, the first end of the low-position filling pipe 14 is located 0.2m to 0.5m above the highest point of the hydraulic support 7.

[0033] The first end of the low-level filling pipe 14 is located above the highest point of the hydraulic support 7. The distance between the first end of the low-level filling pipe 14 and the highest point of the hydraulic support 7 is 0.2 to 0.5 m. The low-level filling pipe 14 conveys foam material (sealing material). The foam material has good expansion properties and a short initial setting time, which is useful for quickly forming a retaining wall above the hydraulic support 7, sealing the gaps around the hydraulic support 7, and preventing the cementing material injected by the high-level filling pipe 15 from leaking.

[0034] Example 6: As an optimization of the above examples, as shown in the appendix Figure 2 , 3 As shown, in step S212, the first end of the high-level filling pipe 15 is not lower than the highest point of the goaf.

[0035] The filling pipeline is divided into a low-level filling pipe 14 and a high-level filling pipe 15. The outlet position (first end) of the high-level filling pipe 15 is located at the highest point of the cut or filling area 9. In this way, the cementing material flows out from the first end of the high-level filling pipe 15 and then flows into the goaf above the hydraulic support 7 under its own weight to form the filling area 9.

[0036] Example 7: As an optimization of the above examples, as shown in the appendix. Figure 1 , 2 As shown in Figure 3, step S3 includes: S31, Install the second filling device 18 on the ground; S32, connect the second end of the high-level filling pipe 15 to the outlet of the second filling device 18; S33, the second filling device 18 prepares a cementing material, the main components of which are a mixture of coal gangue, fly ash and cement; S34, the second filling device 18 fills the cementing material through the high-level filling pipe 15 into the goaf above the sealing area 8 to form the filling area 9.

[0037] Depending on the requirements, the second filling device 18 has the same structure as the first filling device 13. The binding material is a known existing binding material, such as a mixture of coal gangue, fly ash, and cement, with a cement content of 8-10%. The cement ratio can be randomly adjusted to meet the strength requirements of the binding material. Alternatively, a paste-like filling slurry, as disclosed in Chinese patent document CN113860768B, can be used. Every 4 to 10 hydraulic supports 7, the second end of the high-level filling pipe 15 is connected to the second filling device 18. The outlet is connected via a filling pipeline. The filling pipeline used to transport the cementing material passes sequentially through ventilation shaft 3, return air main roadway 4, return air gate, and return air roadway 5, and connects to the second end of the high-level filling pipe 15. The second filling equipment 18 prepares the cementing material. After the cementing material is evenly mixed in the second filling equipment 18 on the ground, it is transported to the goaf to be filled through the filling pipeline and the high-level filling pipe 15. If grout comes out of the overflow pipe 17 when the high-level filling pipe 15 is grouting, it indicates that the goaf has been filled. The exhaust pipe 16 and the overflow pipe 17 are then sealed. Under the support of the hydraulic support 7, the hydraulic support 7 and the filling area 9 jointly bear the load of the filling material above them, and at the same time play a buffering role. The cementing material used for high-level filling is solid waste such as coal gangue and fly ash, which can achieve green and environmentally friendly results.

[0038] Example 8: As an optimization of the above examples, as shown in the appendix Figure 1 , 2 As shown in Figure 3, step S4 includes: S41, every 50 to 100m of backfilling, roof cutting and bottom cutting operations are carried out above the coal mining face, and damage zones and fracture zones are formed on both sides of the goaf; S42, the second filling device 18 prepares high-strength cementing material and fills the high-strength cementing material into the damaged area and fissure area on both sides of the goaf through the high-level filling pipe 15 to form rock pillars 10, the height of which is 6 to 10 meters.

[0039] When the grouting height above hydraulic support 7 reaches 50m to 100m, top and bottom cutting operations are carried out above the coal mining face to sever the ground stress connection, forming a failure zone and fracture zone on both sides of the goaf. High-strength cementing materials are existing known technologies, such as concrete with a cement content greater than 17% (which can be adjusted according to needs), or cement mortar, or a mixture whose main components are coal gangue, fly ash, and cement. The cement ratio is adjusted as needed to meet the strength of the high-strength cementing material, or as in announcement number CN1. The Chinese patent document 19241173B describes a high-strength cementing material based on slag. The second filling device 18 mixes the high-strength cementing material evenly and then fills the damaged and cracked areas formed by the top and bottom cutting operations with the high-strength cementing material, which enhances the adhesion between the filling area 9 and the roof plate 11 and bottom plate 12 of the vertical coal trough, forming a 6 to 10 meter high-strength rock column 10. The rock column 10 is between the sealing area 8 and the filling area 9, so that a self-stabilizing wall base structure can be formed at the cut of the roof plate 11 and the bottom plate 12.

[0040] Two filling systems are set up. The first filling device 13 is a low-level filling system, which is set up at the coal mining face. It relies on a filling pump to transport foam material. The conveying pipeline is relatively short and the cost is low. The second filling device 18 is a high-level filling system, which is set up at the ground. The cementing material is transported to the goaf by gravity, which can reduce the transportation cost.

[0041] The above technical features constitute various embodiments of the present invention, which have strong adaptability and implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.

Claims

1. A method for treating the goaf in a mechanized coal mining face, characterized in that, Backfilling of goaf formed by subduction mining along the dip direction of the coal seam includes the following steps: S1. Hydraulic supports are used to form a support above the vertical coal mining face; S2. After the vertical coal mining face has been mined downwards for a predetermined distance, sealing material is filled above the hydraulic support to form a sealed area; S3. Use cementing materials to pour and form a filling area in the goaf above the hydraulic support; S4. Every 50 to 100 meters of filling, a layer of rock pillars shall be set in the goaf.

2. The method for treating the goaf in a vertical coal mechanized mining face according to claim 1, characterized in that, The coal seam is a steeply inclined coal seam with a dip angle of 60° to 90°. The width of the vertical coal mining face in the strike direction is 200m to 300m, and the length of the vertical coal mining face in the dip direction is 200m to 500m. Low-level reserved holes, high-level reserved holes, exhaust reserved holes and overflow reserved holes are set at intervals on the hydraulic support.

3. The method for treating the goaf in a vertical coal mechanized mining face according to claim 2, characterized in that, In step S2, sealing material is filled above the hydraulic support to form a sealing area, including: S21, seal the gaps between the hydraulic supports below the goaf and the top and bottom plates of the coal seam, as well as the gaps between the hydraulic supports; S22, the goaf between the baffles of the return air roadway and the material transport roadway is sealed off; S23, fill the hydraulic support with sealing material to form a sealing area.

4. The method for treating the goaf in a vertical coal mechanized mining face according to claim 3, characterized in that, Step S23 includes: S231, installing the first filling device on the vertical coal mining face; S232, every 4 to 10 hydraulic supports, a low-level filling pipe, a high-level filling pipe, an exhaust pipe and an overflow pipe are installed in the low-level reserved hole, the high-level reserved hole, the exhaust reserved hole and the overflow reserved hole respectively. The first end of the low-level filling pipe and the first end of the high-level filling pipe are both located above the hydraulic support. S233, connect the second end of the low-level filling pipe to the outlet of the first filling device; S234, The first filling equipment prepares the sealing material; S235, the first filling device fills the sealing material through the low-level filling pipe to the top of the hydraulic support to form a sealing area.

5. The method for treating the goaf in a vertical coal mechanized mining face according to claim 4, characterized in that, In step S212, the first end of the low-position filling pipe is located 0.2m to 0.5m above the highest point of the hydraulic support.

6. The method for treating the goaf in a vertical coal mechanized mining face according to claim 4 or 5, characterized in that, In step S212, the first end of the high-level filling pipe is not lower than the highest point of the goaf.

7. The method for treating the goaf in a vertical coal mechanized mining face according to claim 4 or 5, characterized in that, Step S3 includes: S31, Install the second filling device on the ground; S32, connect the second end of the high-level filling pipe to the outlet of the second filling equipment; S33, the second filling equipment prepares the cementing material; S34, the second filling device fills the goaf above the sealing area with cementing material through the high-level filling pipe to form a filling area.

8. The method for treating the goaf in a vertical coal mechanized mining face according to claim 6, characterized in that, Step S3 includes: S31, Install the second filling device on the ground; S32, connect the second end of the high-level filling pipe to the outlet of the second filling equipment; S33, the second filling equipment prepares the cementing material; S34, the second filling device fills the goaf above the sealing area with cementing material through the high-level filling pipe to form a filling area.

9. The method for treating the goaf in a vertical coal mechanized mining face according to claim 7, characterized in that, Step S4 includes: S41, every 50 to 100m of backfilling, roof cutting and bottom cutting operations are carried out above the coal mining face, and damage zones and fracture zones are formed on both sides of the goaf; S42, the second filling equipment prepares high-strength cementing material, and fills the high-strength cementing material into the damaged area and fissure area on both sides of the goaf through the high-level filling pipe to form rock pillars, the height of which is 6 to 10 meters.

10. The method for treating the goaf in a vertical coal mechanized mining face according to claim 8, characterized in that, Step S4 includes: S41, every 50 to 100m of backfilling, roof cutting and bottom cutting operations are carried out above the coal mining face, and damage zones and fracture zones are formed on both sides of the goaf; S42, the second filling equipment prepares high-strength cementing material, and fills the high-strength cementing material into the damaged area and fissure area on both sides of the goaf through the high-level filling pipe to form rock pillars, the height of which is 6 to 10 meters.

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