Ground surface subsidence reduction treatment method for coal mining

Abstract

The invention relates to the technical field of coal mining, in particular to a coal mining earth surface subsidence reduction treatment method which comprises the steps that an air return way, a connection way and a cut hole which are sequentially communicated are excavated in a continuous mining and continuous filling area; filling mining is divided into two stages, the first filling mining stage comprises the steps that a continuous miner is used for mining a roadway zone, the roadway zone is a goaf roadway after being mined, then the continuous miner is used for mining a roadway zone spaced from the previous goaf roadway, and the previous mined roadway zone is filled while mining is conducted; the second filling and mining stage comprises the step of mining the second roadway zone on the basis of the first filling and mining stage, and the mining is performed in sequence in a spaced and alternate mining and filling manner; the purpose of collaborative operation of filling and coal mining processes can be achieved, the coal gangue is used for filling the roadway belt, the effect of supporting the roadway belt can be achieved, the problem of land occupation of the coal gangue in coal mining is solved, and the settlement reducing effect is remarkable.

Description

Technical Field

[0001] The invention relates to the technical field of coal mining, and in particular to a method for reducing ground subsidence during coal mining. Background Art

[0002] Continuous mining and filling technology is a method of continuous mechanized coal mining in coal mines, usually referring to a mining method with a mechanization rate of more than 95%. This technology uses continuous coal miners and anchor drills to alternately perform excavation and support operations. The operation cycle progress is no more than 7 meters. After the continuous coal miner cuts the coal, the shuttle car takes the coal and transports it to the feeder crusher. The feeder crusher crushes the coal and evenly transports it to the belt conveyor, and finally sends the coal to the ground.

[0003] As environmental issues have gradually received widespread attention, accelerating the construction of green mines and achieving zero waste rock emissions has become a top priority. However, in actual operation, the current backfill mining technology is difficult to achieve collaborative operation with the coal mining process, or the degree of collaborative operation is low, which not only seriously affects the output of the coal mining face, but also makes the relationship between mining and backfilling tense, limiting the promotion and application of backfill mining technology.

[0004] During coal mining and washing operations, coal mines produce a large amount of gangue, which not only occupies a large amount of land resources, but also causes dust pollution and the release of harmful gases. Compared with traditional mining technology, the continuous mining and filling technology can achieve a resource recovery rate of more than 90%, significantly improving the recycling rate of coal resources. By reducing gangue emissions, it effectively solves the pollution and land occupation problems of coal mines, and plays an important role in the comprehensive protection of the geological environment. Summary of the invention

[0005] In view of the technical problems that it is difficult to achieve coordinated operation of the filling process and the coal mining process in the prior art, and that the coal mining process is prone to cause surface subsidence, the present invention provides a method for surface subsidence reduction and control in coal mining, which solves the technical problems that it is difficult to achieve coordinated operation of the filling process and the coal mining process in the prior art, and uses a gangue mixture to fill the tunnel belt to support the tunnel belt, thereby achieving the purpose of controlling ground subsidence, improving mining and filling efficiency, and solving the problem of land occupation by gangue during the mining process.

[0006] A method for reducing ground subsidence during coal mining includes excavating a return air lane, a connecting lane, and a cut hole that are connected in sequence in the mining area; dividing the area between the return air lane, the connecting lane, and the cut hole into at least 6 lane belts, the lane belts are divided into odd-numbered lane belts and even-numbered lane belts, and using a continuous coal mining machine to perform filling mining on the lane belts; Backfill mining includes the first backfill mining stage and the second backfill mining stage. The specific steps are as follows: (1) The first filling mining stage is to mine the odd-numbered lane belts, and the steps are as follows: use a continuous coal mining machine to mine the first odd-numbered lane belt, and after mining, mine the second odd-numbered lane belt, and fill the first odd-numbered lane belt while mining the second odd-numbered lane belt; after mining the second odd-numbered lane belt, immediately mine the third odd-numbered lane belt, and fill the second odd-numbered lane belt while mining the third odd-numbered lane belt, and repeat the above operations until the last odd-numbered lane belt is filled; (2) The second filling mining stage is to mine the even-numbered roadway belts, and the steps are as follows: use a continuous coal mining machine to mine the first even-numbered roadway belt, and after mining, mine the second even-numbered roadway belt, and fill the first even-numbered roadway belt while mining the second even-numbered roadway belt; after mining the second even-numbered roadway belt, immediately mine the third even-numbered roadway belt, and fill the second even-numbered roadway belt while mining the third even-numbered roadway belt, and repeat the above operations until the last even-numbered roadway belt is filled.

[0007] Furthermore, after the last odd-numbered row of the first filling mining stage is mined, the first even-numbered row of laneway belts can be mined at the same time, and the last odd-numbered row of laneway belts can be filled while the first even-numbered row of laneway belts are mined.

[0008] Furthermore, the slope of the roadway belt is 18°-20° and its length is 40m.

[0009] Furthermore, after the tunnel belt is mined, the lower end of the goafed tunnel belt is sealed by building a wall.

[0010] Furthermore, a mixture of cement slurry and waste rock is injected into the top of the goafed tunnel belt after the tunnel belt is mined to complete the filling.

[0011] Furthermore, the injected cement slurry consists of fly ash, cement and water in a mass ratio of 3 parts, 3 parts and 4 parts.

[0012] Furthermore, after the filling is completed, the goaf roadway is sealed to ensure that the cement slurry and gangue mixture can fully solidify and harden in the goaf roadway.

[0013] Furthermore, the sealing treatment is performed by spraying sealing materials or installing sealing plates to prevent the intrusion of air and moisture and ensure the durability of the supporting effect.

[0014] The beneficial effects of the present invention are: (1) By using a continuous coal miner to mine the tunnel strip separated from the previous goaf, the previous goaf can be filled while the continuous coal miner is mining the next tunnel strip, thereby achieving the purpose of coordinated operation of the filling process and the coal mining process.

[0015] (2) Filling the tunnel belt can support the tunnel belt and achieve the effect of reducing surface subsidence.

[0016] (3) The tunnel belt is filled with coal gangue, which solves the problem of land occupation by coal gangue during the mining process.

[0017] (3) This method also has the advantages of simple operation, low cost, and significant subsidence reduction effect, and is suitable for various types of coal mining. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] 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 or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 It is a schematic diagram of the mining structure of a specific implementation method of the present invention.

[0020] Figure 2 It is a schematic diagram of the implementation of the continuous mining and charging stages in a specific implementation mode of the present invention.

[0021] Figure 1 Among them, 1-odd-numbered laneway belt, 1-1-the first odd-numbered laneway belt, 1-2-the second odd-numbered laneway belt, 1-3-the third odd-numbered laneway belt, 1-4-the fourth odd-numbered laneway belt, 2-even-numbered laneway belt, 2-1-the first even-numbered laneway belt, 2-2-the second even-numbered laneway belt, 2-3-the third even-numbered laneway belt, 2-4-the fourth even-numbered laneway belt, 3-return air lane, 4-connecting lane, 5-cutting eye. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings 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 should fall within the scope of protection of the present invention.

[0023] Example 1 like Figure 1 , Figure 2As shown, a method for reducing ground subsidence in coal mining includes using a continuous coal mining machine to mine in a mining area, mining a return air tunnel 3, a connecting tunnel 4, and a cutting eye 5 that are connected in sequence; the connecting tunnel 4 is used as a gangue transportation tunnel and a coal transportation tunnel respectively; the area between the return air tunnel 3, the connecting tunnel 4, and the cutting eye 5 is divided into 10 tunnel belts, and the tunnel belts are mined by a continuous coal mining machine. After the tunnel belts are mined, they become goaf tunnels with a slope of 18°-20° and a length of 40m; the 10 tunnel belts are backfilled and mined by a continuous coal mining machine in the mining area, and the backfilling mining is carried out in an alternating interval manner. The backfilling mining includes a first backfilling mining stage and a second backfilling mining stage, and the tunnel belts are divided into an odd-numbered tunnel belt 1 and an even-numbered tunnel belt 2.

[0024] The first filling mining stage is to mine the odd-numbered laneway belt 1, and the steps are: use a continuous coal mining machine to mine the first odd-numbered laneway belt 1-1, and after mining, mine the second odd-numbered laneway belt 1-2, and fill the first odd-numbered laneway belt 1-1 while mining the second odd-numbered laneway belt 1-2; after mining the second odd-numbered laneway belt 1-2, immediately mine the third odd-numbered laneway belt 1-3, and fill the second odd-numbered laneway belt 1-2 while mining the third odd-numbered laneway belt 1-3; after mining the third odd-numbered laneway belt 1-3, mine the fourth odd-numbered laneway belt 1-4, and fill the third odd-numbered laneway belt 1-3 while mining the fourth odd-numbered laneway belt 1-4, and repeat the above operations until the last odd-numbered laneway belt is filled, so as to achieve the effect of coordinated completion of the filling process and the coal mining process; The second filling mining stage is to mine the even-numbered laneway belt 2, and the steps are: use a continuous coal mining machine to mine the first even-numbered laneway belt 2-1, and after mining, mine the second even-numbered laneway belt 2-2, and fill the first even-numbered laneway belt 2-1 while mining the second even-numbered laneway belt 2-2; after mining the second even-numbered laneway belt 2-2, immediately mine the third even-numbered laneway belt 2-3, and fill the second even-numbered laneway belt 2-2 while mining the third even-numbered laneway belt 2-3; after mining the third even-numbered laneway belt 2-3, mine the fourth even-numbered laneway belt 2-4, and fill the third even-numbered laneway belt 2-3 while mining the fourth even-numbered laneway belt 2-4, and repeat the above operations until the last even-numbered laneway belt is filled, so as to achieve the effect of coordinated completion of the filling process and the coal mining process.

[0025] The filling materials in the mining tunnel belts in the first filling mining stage and the second filling mining stage are both cement slurry and gangue mixture. The raw materials of the injected cement slurry are composed of fly ash, cement and water, and the mass ratio is 3 parts, 3 parts and 4 parts. The cement slurry and gangue mixture is injected into the interior of the empty tunnel from the top of the empty tunnel belt and waits for it to solidify and harden. With the help of the buoyancy of the cement slurry, the gangue is carried to the end position of the branch tunnel. The lower end of the empty tunnel is sealed by walling. After the grouting and filling of the gangue mixture are completed, the empty tunnel is sealed. The sealing treatment can be carried out by spraying sealing materials Or install sealing plates, etc. to ensure that the grouting and gangue mixture can fully solidify and harden in the goaf, prevent the intrusion of air and moisture, and ensure the durability of the support effect; after the grouting and gangue mixture solidify and harden, conduct regular inspections of the surface to observe the subsidence of the surface. By comparing and analyzing the monitoring data, the settlement reduction effect of the continuous mining and filling support tunnel method can be evaluated, and necessary adjustments and optimizations can be made according to actual conditions. If it is found that the settlement reduction effect in certain areas is not good, these areas can be re-grouted and filled with gangue mixture to improve the support effect.

[0026] Example 2 The difference between Example 2 and Example 1 is that after the last odd-numbered column of the first filling mining stage is mined, the first even-numbered column of tunnel belts is immediately mined, and the last odd-numbered column of tunnel belts is filled while the mining of the first even-numbered column of tunnel belts is completed. This can improve the efficiency of mining and filling and better realize the coordinated operation of mining technology and coal mining technology.

[0027] Although the present invention has been described in detail with reference to the accompanying drawings and in combination with the preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person of ordinary skill in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions shall be within the scope of the present invention. Any person of ordinary skill in the art may easily think of changes or substitutions within the technical scope disclosed by the present invention, and these shall be within the scope of protection of the present invention.

Claims

1. A method for reducing ground subsidence in coal mining, comprising excavating a return air tunnel, a connecting tunnel and a cut hole which are connected in sequence in the mining area; characterized in that: The area between the return air lane, the connecting lane and the cut-off is divided into at least 6 lane belts, which are divided into odd-numbered lane belts and even-numbered lane belts. The lane belts are backfilled and mined using a continuous coal mining machine. Backfill mining includes the first backfill mining stage and the second backfill mining stage. The specific steps are as follows: (1) The first filling mining stage is to mine the odd-numbered lane belts, and the steps are as follows: use a continuous coal mining machine to mine the first odd-numbered lane belt, and after mining, mine the second odd-numbered lane belt, and fill the first odd-numbered lane belt while mining the second odd-numbered lane belt; after mining the second odd-numbered lane belt, immediately mine the third odd-numbered lane belt, and fill the second odd-numbered lane belt while mining the third odd-numbered lane belt, and repeat the above operations until the last odd-numbered lane belt is filled; (2) The second filling mining stage is to mine the even-numbered roadway belts, and the steps are as follows: use a continuous coal mining machine to mine the first even-numbered roadway belt, and after mining, mine the second even-numbered roadway belt, and fill the first even-numbered roadway belt while mining the second even-numbered roadway belt; after mining the second even-numbered roadway belt, immediately mine the third even-numbered roadway belt, and fill the second even-numbered roadway belt while mining the third even-numbered roadway belt, and repeat the above operations until the last even-numbered roadway belt is filled.

2. A method for reducing ground subsidence during coal mining as claimed in claim 1, characterized in that: After the last odd-numbered row of the first filling mining stage is mined, the first even-numbered row of tunnel belts will be mined immediately. When the mining of the first even-numbered row of tunnel belts is completed, the last odd-numbered row of tunnel belts will be filled.

3. A method for reducing ground subsidence during coal mining as claimed in claim 1, characterized in that: The slope of the tunnel belt is 18°-20° and its length is 40m.

4. A method for reducing ground subsidence during coal mining as claimed in claim 1, characterized in that: After the tunnel belt is mined, the lower end of the goaf tunnel belt is sealed by building a wall.

5. A method for reducing ground subsidence during coal mining as claimed in claim 1, characterized in that: After the tunnel belt is mined, a mixture of cement slurry and gangue is injected into the top of the goaf tunnel belt to complete the filling.

6. A method for reducing ground subsidence during coal mining as claimed in claim 5, characterized in that: The injected cement slurry is composed of fly ash, cement and water in a mass ratio of 3 parts, 3 parts and 4 parts.

7. A method for reducing ground subsidence during coal mining as claimed in claim 1, characterized in that: After the filling is completed, the goaf tunnel zone is sealed.

8. A method for reducing ground subsidence during coal mining as claimed in claim 7, characterized in that: The sealing process is carried out by spraying sealing materials or installing sealing plates.

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