Underground mining, selecting and filling integrated coal gangue filling and replacing section coal pillar method

Abstract

The invention provides an underground mining, selecting and filling integrated coal gangue filling and replacing section coal pillar method, and relates to the technical field of coal stoping, and the method comprises the following steps: respectively forming a transportation crossheading and an air return crossheading on the left side and the right side of a section coal pillar, and communicating the transportation crossheading with the air return crossheading through a crossheading connection roadway; and according to the serial number sequence, the strips with the serial numbers being even numbers are subjected to stoping and filling in sequence, and then the strips with the serial numbers being odd numbers are subjected to stoping and filling. An odd-even sectional type stoping method is adopted for the section coal pillars, after stoping, filling slurry is used for preparing a chamber to sort coarse coal and coal gangue, the coal gangue is made into coal gangue filling slurry to be filled into the goaf of the section coal pillars, integrated operation of stoping, sorting and filling is achieved, the method can be suitable for an underground stoping area with multiple working faces, coal pillar resources are efficiently recycled, and the mining efficiency is improved. The method has a good application prospect and a wide application range.

Description

Technical Field

[0001] The invention relates to the technical field of coal recovery, and in particular to a method for underground mining, selection and filling integrated coal gangue filling and replacement of section coal pillars. Background Art

[0002] During the coal mining process, the retention of section coal pillars causes a large amount of coal resources to remain underground, resulting in a waste of coal resources.

[0003] Coal mine gangue filling mining technology is a technology that uses gangue as filling material to fill the goaf during coal mining. The gangue raw materials are sorted on the ground and prepared into filling materials, which are then transported underground for filling.

[0004] In view of this, how to provide a method for using coal gangue to fill and replace section coal pillars to avoid waste of coal resources is an urgent problem that technical personnel in this field need to solve. Summary of the invention

[0005] The purpose of the present invention is to provide a method for underground mining, selection and filling integrated coal gangue filling replacement section coal pillar to solve the problems existing in the prior art.

[0006] To achieve the above object, the present invention provides a method for underground mining, selection and filling integrated coal gangue filling and replacement of section coal pillars, comprising the following steps:

[0007] S1: A section coal pillar is formed between adjacent working faces. A transport chute and a return air chute are respectively opened on the left and right sides of the section coal pillar. The transport chute and the return air chute are connected by a chute connecting lane. A movable belt conveyor is arranged in the chute connecting lane, and a belt conveyor is arranged in the transport chute;

[0008] S2: Divide the section coal pillar evenly into multiple strips along the length direction of the transport chute, and number the strips A1, A2, A3 to An in sequence;

[0009] S3: Mining the strips with even numbers in the order of numbers. The mining direction is from the return air chute to the transport chute. The mined coal is output through the movable belt conveyor and the belt conveyor.

[0010] S4: Fill the strips with even numbers in order, using coal gangue filling slurry, which is transported from the return air chute to the strips;

[0011] S5: mining the strips with odd numbers in the order of numbers, with the mining direction from the return air chute to the transport chute, and the mined coal is output through the movable belt conveyor and the belt conveyor;

[0012] S6: Fill the odd-numbered strips in order of numbering, using coal gangue filling slurry, and the coal gangue filling slurry is transported from the return air chute to the strips.

[0013] Furthermore, the connecting tunnel of the drift is located 10-15m below the supporting pressure zone of the working face.

[0014] Furthermore, in step S1, the transport chute is formed by the transport uphill excavation working face, and the return air chute is formed by the return air uphill excavation working face.

[0015] Furthermore, in steps S3-S6, when the strip numbered An is mined, the strip numbered An-2 is used as the connecting tunnel of the drift and a movable belt conveyor is arranged to fill the strip numbered An-4 or the original connecting tunnel of the drift.

[0016] Furthermore, the thickness of the strip is 5 m. In steps S3-S6, the working face and the strip are mined simultaneously. The strip mining speed and filling speed are both 5 m / d, and the mining speed of the working face is 4 m / d.

[0017] Furthermore, in steps S3 and S5, the strips after mining form goafs, anchor rods and anchor cables are driven into the roof of the goafs, and anchor rods are driven into both sides of the goafs.

[0018] Furthermore, in steps S3 and S5, the coal is output to the filling slurry preparation chamber via a movable belt conveyor and a belt conveyor, the coal is sorted into coarse carbon and gangue, the coarse coal is output by transporting up the mountain, the gangue is crushed to form gangue filling slurry, and the gangue filling slurry is transported to the strip through the return air up the mountain and the return air chute.

[0019] Further, steps S1-S6 are repeated to mine all working faces, and all section coal pillars are mined and filled.

[0020] The present invention discloses the following technical effects:

[0021] The present application establishes a complete method for replacing segmented coal pillars with coal gangue filling. The segmented coal pillars adopt an odd-even segmented mining method. After mining, the filling slurry is used to prepare the chamber to sort coarse coal and coal gangue. The coal gangue is made into coal gangue filling slurry and filled into the goaf of the segmented coal pillars, realizing the integrated operation of mining, sorting and filling. It can be applied to underground mining areas with multiple working faces, efficiently recover coal pillar resources, and has good application prospects and a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 This is a schematic diagram of the initial stage of coal pillar recovery at the first working face and the first section;

[0024] Figure 2 It is a schematic diagram of the mining of the first working face and the mining and filling of the coal pillar in the first section;

[0025] Figure 3 This is a schematic diagram of the initial stage of coal pillar mining at the second working face and the second area;

[0026] Figure 4 It is a schematic diagram of the mining of the second working face and the mining and filling of the coal pillar in the second section;

[0027] Figure 5 Schematic diagram of strip division;

[0028] Figure 6 Schematic diagram of goaf formed for strip mining;

[0029] Among them, 1. Transport up the mountain; 2. Track up the mountain; 3. Return air up the mountain; 4. First transport chute; 5. First return air chute; 6. Chute connecting tunnel; 7. First section coal pillar; 8. First working face; 9. Second working face; 10. Second transport chute; 11. Second return air chute; 12. Gangue connecting tunnel; 13. Filling slurry preparation chamber; 14. Coal transport connecting tunnel; 15. Coal connecting tunnel; 16. Gangue filling retaining wall; 17. Filling body; 18. Second section coal pillar. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] like Figure 1-Figure 6As shown, the embodiment of the present invention provides a method for underground mining, selection and filling integrated coal gangue filling and replacement of segmented coal pillars, which is applied to a coal mining mine. The parameters of the mine are as follows: the production capacity is 3 million tons / year, the length of the working face is L, the width of the segmented coal pillar is W, and the average thickness of the coal seam is H. 5m; the working face advances 5 times a day, each cut is 0.8m, the advancement speed x is 4m / d, the coal seam gangue content μ is 10%, and the density of coal ρ is 1.4t / m 3 , the density of gangue is ρ'1.8t / m 3 .

[0033] The following steps are involved:

[0034] S1: This embodiment is described with three working faces in the initial stage of mining, the first working face 8 is on the left, the second working face 9 is in the middle, and the third working face is on the right. The first section coal pillar 7 is between the first working face 8 and the second working face 9, and the second section coal pillar 18 is between the second working face 9 and the third working face. A transport chute and a return air chute are respectively opened on the left and right sides of the section coal pillar. The transport chute is formed from the transport uphill 1 excavation working face to the mining boundary, and the return air chute is formed from the return air uphill 3 excavation working face to 10-15m below the supporting pressure area of ​​the working face.

[0035] It should be noted that in coal mining, transport uphill 1, track uphill 2 and return air uphill 3 are three inclined tunnels with different functions, and they each undertake different tasks:

[0036] Transport up the mountain1

[0037] Transport uphill 1 refers to an inclined tunnel used to transport coal, which is usually equipped with a belt conveyor, so it is also called belt uphill. Its main function is to transport coal in the mining area to the ground or other processing locations. The layout of transport uphill 1 is uphill, that is, it is excavated from the main transport tunnel upward along the coal seam or rock stratum.

[0038] Tracks up the hill 2

[0039] Track uphill 2 is an inclined tunnel for transporting materials, equipment and gangue. It is arranged with tracks and mainly uses mine cars or electric locomotives for transportation. It is not only responsible for transportation, but also can be used as an auxiliary transportation tool to transport personnel and materials. Track uphill 2 is also a tunnel that slopes upward from the transport layer.

[0040] Back to the mountain 3

[0041] The return air uphill 3 is an inclined tunnel used for mine ventilation. Its main function is to guide the polluted air (air containing harmful substances such as gas and coal dust) in the mining area into the total return air system of the mine. This ensures the circulation of fresh air in the mining area and provides a safe working environment for miners. The return air uphill 3 is also excavated from the main transport tunnel upward along the coal seam or rock stratum.

[0042] These three types of uphill tunnels are very important in the production system of coal mines. Together, they ensure the efficient production and safe operation of coal mines.

[0043] Specifically, the first transport chute 4 and the first return air chute 5 are located on the left and right sides of the first working face 8, and the second transport chute 10 and the second return air chute 11 are located on the left and right sides of the second working face 9. The first transport chute 4 and the first return air chute 5 are connected through a chute connecting lane 6, which is located 10-15m below the supporting pressure zone of the working face. The chute connecting lane 6 is arranged with a movable belt conveyor, and the first transport chute 4 is arranged with a belt conveyor;

[0044] S2: evenly divide the section coal pillar into multiple strips along the length direction of the first transport chute 4, and number the strips A1, A2, A3 to A10 in sequence;

[0045] S3: Mining the first working face 8 and the first section coal pillar 7 at the same time. Mining the strips with even numbers in the order of numbers, with the mining direction from the first return air chute 5 to the first transport chute 4, and the mining direction is substantially perpendicular to the length direction of the first transport chute 4. The mined coal is transferred to the chute connecting tunnel 6 by a loader and then to the movable conveyor, and then outputted via the movable belt conveyor and the belt conveyor;

[0046] S4: Fill the strips with even numbers in order of numbering, using gangue filling slurry, which is transported from the return air chute to the strips; not all strips are mined before filling. When the strip numbered A2 is mined, the chute connecting tunnel 6 is filled with gangue filling slurry to form a gangue filling retaining wall 16, and the strip numbered A4 is mined at the same time. At this time, the goaf of the strip numbered A2 is used as the new goaf connecting tunnel 6. Similarly, in the subsequent mining and filling process, when the strip numbered An is mined, the strip numbered An-2 is used as the new goaf connecting tunnel 6 and a movable belt conveyor is arranged to fill the strip numbered An-4. In steps S3 and S5, the strips after mining form goafs, and anchor rods and anchor cables are installed on the top plate of the goaf, and anchor rods are installed on both sides of the goaf.

[0047] S5: mining the strips with odd numbers in the order of numbers, with the mining direction from the return air chute to the transport chute, and the mined coal is output through the movable belt conveyor and the belt conveyor;

[0048] S6: Fill the odd-numbered strips in order, using gangue filling slurry, which is transported from the return air chute to the strips. The width y of each strip is 5m, and the mining and filling speed y of the first section coal pillar 7 is 5m / d; the gangue filling retaining wall 16 is compacted to form a filling body 17, and the crushing expansion coefficient β of the filling body 17 is 0.05.

[0049] In steps S3 and S5, the coal mined from the first working face 8 and the first section coal pillar 7 is transported to the filling slurry preparation chamber 13 via the transport chute, the transport uphill 1 and the coal transportation connecting tunnel 14. The filling slurry preparation chamber 13 sorts the coal into coarse carbon and coal gangue, and the coarse coal is transferred back to the transport uphill 1 for output through the coal connecting tunnel 15. The coal gangue is crushed to make coal gangue filling slurry, and the coal gangue filling slurry is transported to the strip through the coal gangue connecting tunnel 12, the return air uphill 3 and the return air chute by a grouting pump.

[0050] Numerical simulation is used to obtain the stress increase area during mining of the second working face 9. When the coal gangue filling retaining wall 16 is fully compacted to form a filling body 17, and the filling body 17 closest to the transportation uphill 1 is 10-15m away from the stress increase area of ​​the second working face 9, the mining and filling work of the second working face 9 and the second section coal pillar 18 is started.

[0051] Repeat the above steps until all working faces and sections of coal pillars are mined and filled. When the distance between the working face and the filling slurry preparation chamber 13 reaches 1000-1200m, a new filling slurry preparation chamber 13 can be set up.

[0052] In the above steps, in order to ensure that the filling slurry preparation chamber 13 can prepare sufficient coal gangue filling slurry, various working parameters during mining should be limited. The following conditions must be met:

[0053] LHxμρ'+WHyμρ'>WHyρ'(1 / (1+β))

[0054] It can be obtained that L>13W; assuming that the width of the section coal pillar is designed to be 20m, the working face length is at least 260m; assuming that the actual production time of the mine is 330 days a year, 9,100 tons of coal must be produced every day. It can be calculated that the required working face length is 295m, which can meet the filling requirements.

[0055] According to the production capacity of the filling slurry preparation chamber 13, during the filling of one strip, the filling slurry preparation chamber 13 must be able to sort out the amount of gangue required for the next filling strip, that is, WHyρ' (1 / (1+β)). The production capacity of the filling slurry preparation chamber 13 is at least 1029t / d.

[0056] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0057] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for underground mining, dressing and filling integrated coal gangue filling and replacement section coal pillar, characterized in that: The following steps are involved: S1: A section coal pillar is formed between adjacent working faces, and a transport chute and a return air chute are respectively opened on the left and right sides of the section coal pillar. The transport chute and the return air chute are connected by a chute connecting tunnel (6). A movable belt conveyor is arranged in the chute connecting tunnel (6), and a belt conveyor is arranged in the transport chute; S2: Divide the section coal pillar evenly into multiple strips along the length direction of the transport chute, and number the strips A1, A2, A3 to An in sequence; S3: Mining the strips with even numbers in the order of numbers. The mining direction is from the return air chute to the transport chute. The mined coal is output through the movable belt conveyor and the belt conveyor. S4: Fill the strips with even numbers in order, using coal gangue filling slurry, which is transported from the return air chute to the strips; S5: mining the strips with odd numbers in the order of numbers, with the mining direction from the return air chute to the transport chute, and the mined coal is output through the movable belt conveyor and the belt conveyor; S6: Fill the odd-numbered strips in order according to the numbering sequence, using coal gangue filling slurry, and the coal gangue filling slurry is transported from the return air chute to the strips.

2. The method for underground mining, selection and filling integrated coal gangue filling and replacement section coal pillar according to claim 1 is characterized in that: The connecting tunnel (6) is located 10-15m below the supporting pressure zone of the working face.

3. The method for underground mining, selection and filling integrated coal gangue filling and replacement section coal pillar according to claim 2 is characterized in that: In step S1, a transport chute is formed by a transport uphill (1) excavation working face, and a return air chute is formed by a return air uphill (3) excavation working face.

4. The method for underground mining, selection and filling integrated coal gangue filling and replacement of section coal pillars according to claim 3 is characterized in that: In steps S3-S6, when the strip numbered An is mined, the strip numbered An-2 is used as the connecting tunnel (6) of the drift and a movable belt conveyor is arranged to fill the strip numbered An-4 or the original connecting tunnel (6).

5. The method for underground mining, selection and filling integrated coal gangue filling and replacement section coal pillar according to claim 4 is characterized in that: The thickness of the strip is 5m. In steps S3-S6, the working face and the strip are mined simultaneously. The strip mining speed and filling speed are both 5m / d, and the working face mining speed is 4m / d.

6. The method for underground mining, selection and filling integrated coal gangue filling and replacement section coal pillar according to claim 5, characterized in that: In steps S3 and S5, the strips after mining form goafs, anchor rods and anchor cables are driven into the roof of the goafs, and anchor rods are driven into both sides of the goafs.

7. The method for underground mining, selection and filling integrated coal gangue filling and replacement of section coal pillars according to claim 5, characterized in that: In steps S3 and S5, the coal is output to the filling slurry preparation chamber (13) via a movable belt conveyor and a belt conveyor, and the coal is sorted into coarse carbon and coal gangue. The coarse coal is output by transporting uphill (1), and the coal gangue is crushed to form coal gangue filling slurry. The coal gangue filling slurry is transported to the strip through the return air uphill (3) and the return air chute.

8. The method for underground mining, selection and filling integrated coal gangue filling and replacement of section coal pillars according to claim 7, characterized in that: Repeat steps S1-S6 to mine all working faces and mine and fill all section coal pillars.

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