Coal gangue goaf filling pile forming control system and method

Abstract

The invention relates to a coal gangue goaf filling pile forming control system and method. The system comprises a coal ash bin, an underground preparation assembly, a filling material conveying assembly and an adhesive spraying mechanism. The underground preparation assembly comprises a screening table and a multi-stage crushing mechanism. The coal gangue is subjected to secondary crushing, so that the particle size distribution of the solid filling material is small, a chain is not prone to being blocked when the solid filling material is conveyed to a scraper conveyor of a working face, transportation is convenient, and the transportation stability is improved. Through a method of spraying an adhesive on a solid filling material, the consolidation property between solid materials is improved, the preparation of the coal gangue-based self-stabilizing functional filling material is realized, and the material slip-back can be reduced or avoided in the filling and tamping process, so that the tamping frequency is reduced, and the filling efficiency is improved. The coal gangue goaf filling pile forming control method is safe, reliable, convenient to use and high in applicability, solid waste gangue can be efficiently treated, part of the goaf can be filled, and the working face mine pressure appearance phenomenon is relieved.

Description

Technical Field

[0001] The invention relates to the technical field of gangue filling materials, in particular to a control system and method for forming a filling pile in a gangue goaf area. Background Art

[0002] Solid filling mining technology involves the use of filling materials such as gangue to backfill the mined areas, which not only helps to obtain coal resources, but also effectively prevents the collapse of the ground in the mined areas and actively protects the ecological environment.

[0003] In the existing solid filling mining technology, after the solid material is transported to the goaf, it needs to be pushed by the compaction mechanism of the hydraulic support to shape the loose solid filling material. However, ordinary solid materials will slide back to a certain extent after compaction, so multiple compactions are required to achieve the ideal filling rate, which restricts the improvement of solid filling mining efficiency.

[0004] In view of the above technical problems, it is necessary to develop a control system and method for forming a filling pile in a gangue goaf area. Summary of the invention

[0005] The purpose of the present invention is to address the problems existing in the prior art and to provide a simple, safe and efficient control system and method for forming a filling pile in a coal gangue goaf area. Through secondary crushing of the coal gangue, the particle size distribution of the solid filling material is smaller, and it is not easy to get stuck on the scraper conveyor when transported to the working face, thus facilitating transportation. The solid filling material is designed to be sprayed with an adhesive to improve the bonding performance between the filling materials, enhance the self-stability of the filling pile, form a coal gangue-based self-stabilizing functional filling material, and reduce the number of compaction times.

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

[0007] A control system for forming a filling pile in a gangue goaf area, comprising:

[0008] Fly ash silos for storing fly ash;

[0009] An underground preparation assembly for processing coal gangue mixture, comprising a screening table and a multi-stage crushing mechanism, wherein the screening table and the multi-stage crushing mechanism respectively screen and crush the filling raw materials into target particle sizes, wherein the multi-stage crushing mechanism comprises a drum crusher and a double-roller sand making machine;

[0010] A filling material conveying assembly for conveying materials, comprising a transfer conveyor, a belt conveyor and a gangue belt, wherein the gangue belt is located between the output end of the screening table and the input end of the drum crusher, the belt conveyor receives materials from the fly ash bin, the roller sand making machine and the drum crusher through the conveyor belt, the output end of the belt conveyor is connected to the input end of the transfer conveyor, and the output end of the transfer conveyor extends to the area to be filled;

[0011] The binder spraying mechanism for modifying coal gangue mixture comprises a binder pipeline, a sprayer is arranged at the bottom of the binder pipeline, the binder is transported inside the binder pipeline and sprayed on the coal gangue mixture through the sprayer to generate coal gangue-based functional filling material.

[0012] Preferably, the filling pile of the gangue goaf is located in the tunnel between the roof rock layer and the floor rock layer, and a sorting chamber and a preparation chamber are reserved in the tunnel;

[0013] A passage runs through the separation chamber and the preparation chamber, and the gangue belt is arranged along the passage.

[0014] Preferably, the screening platform is arranged in the sorting chamber, and the fly ash bin, drum crusher and double-roller sand making machine are all arranged in the preparation chamber.

[0015] Preferably, a material distribution table is provided at the output end of the drum crusher, and the output end of the material distribution table is respectively connected to a belt conveyor and a roller sand making machine through two conveyor belts; the drum crusher and the roller sand making machine respectively perform preliminary crushing and secondary crushing of the conveyed gangue.

[0016] Preferably, the adhesive pipeline extends from the well to the inside of the preparation chamber, and the adhesive pipeline is arranged along the direction of the belt conveyor and installed directly above the belt conveyor. The vertical distance between the adhesive pipeline and the belt conveyor is set to 1.5m.

[0017] Preferably, the sprayer comprises a spray pipe and a spray head, and the top end and the bottom end of the spray pipe are respectively connected to the adhesive pipeline and the spray head.

[0018] Preferably, the number of the sprayers is set to be multiple, and the multiple sprayers are distributed in a linear array along the direction of the adhesive pipeline, and the interval length between two adjacent sprayers is D, which is calculated as follows:

[0019] D=2(1+δ)R

[0020] In the formula, δ is the surplus coefficient, which is determined by experience;

[0021] R is the spray radius of the sprinkler for the belt conveyor.

[0022] A method for controlling the formation of a filling pile in a gangue goaf area adopts the above-mentioned gangue goaf area filling pile formation control system to perform operations, and comprises the following steps:

[0023] S1. Determine the required compressive strength of the filling body in the goaf, and select the optimal ratio of the coal-gangue mixture according to the required compressive strength. The process is as follows:

[0024] S1.1. Determine the required compressive strength of the filling body in the goaf by combining field measurement with numerical simulation;

[0025] S1.2. According to laboratory tests, the dosage of modified coal gangue, ordinary gangue and fly ash was studied, and the strength of the filling material under different modified coal gangue ratio conditions was measured;

[0026] S1.3. In the results of S1.2, the optimal mix ratio is selected as the one that meets the compressive strength requirements and has the lowest modified gangue content;

[0027] S2. Design underground preparation components according to the underground mine layout. The process is as follows:

[0028] S2.1. Construct a sorting chamber and a preparation chamber in the tunnel between the roof rock layer and the floor rock layer, and build a gangue storage bin near the sorting chamber;

[0029] S2.2, install a screening table in the sorting chamber, install a fly ash bin, a drum crusher, a material distribution table and a roller sand making machine in the preparation chamber, and connect the screening table, fly ash bin, drum crusher, material distribution table and roller sand making machine to each other through a filling material conveying component to form a filling pile forming system integrating processing and conveying;

[0030] S2.3. Arrange adhesive pipelines with sprinklers along the direction of the belt conveyor;

[0031] S3, screening and transporting the gangue underground, using the drum crusher and roller sand making machine to initially crush the gangue, and transporting a portion of it directly to the belt conveyor according to the proportion as ordinary gangue; the other portion is transported to the roller sand making machine for further crushing, and the gangue is modified by the action of high-energy mechanical force, and the gangue passing through the roller sand making machine is processed into modified gangue;

[0032] S4, mixing the modified coal gangue, ordinary gangue and fly ash according to the proportion obtained in S1 to form a coal gangue mixture;

[0033] S5. The binder is transported through the binder pipeline and sprayed evenly onto the coal gangue mixture from the sprinkler to form a 3-5 mm covering layer on its surface. After mixing, a coal gangue-based functional filling material is formed and sent to the working face of the area to be filled through a transfer conveyor for filling.

[0034] Preferably, in S1, the total amount of fly ash and gangue is set to be:

[0035] Gangue accounts for 75-85%;

[0036] Fly ash accounts for 15-25%;

[0037] The mass ratio of the modified coal gangue to the ordinary gangue in the total amount of gangue is set to 1:1.

[0038] Preferably, the binder comprises, by weight: 20 parts of cement, 2 parts of cement early strength activator, 3 parts of accelerating agent and 75 parts of water.

[0039] In the above technical solution, compared with the prior art, the technical effects and advantages provided by the present invention are as follows:

[0040] 1. By spraying a binder on the solid filling material, the consolidation between the solid materials is improved, and the preparation of the gangue-based self-stabilizing functional filling material is realized, which can reduce or avoid the material sliding back during the filling and compaction process, thereby reducing the number of compaction times and improving the filling efficiency. This method is safe and reliable, easy to use, and has strong applicability. It can not only efficiently treat solid waste gangue, but also fill part of the goaf and alleviate the phenomenon of mine pressure on the working face.

[0041] 2. The particle size distribution of solid materials has an important influence on transportation efficiency. The present invention reduces the particle size distribution of solid filling materials by secondary crushing of coal gangue, which makes it less likely to get stuck on the scraper conveyor when transported to the working surface, making transportation easier. It improves the stability of transportation, reduces downtime caused by stuck chains, and improves overall operating efficiency. The present invention is of great significance in large-scale processing of gangue and improving solid filling efficiency.

[0042] 3. The treatment of gangue underground is an important link to improve resource utilization and reduce environmental impact. The application of the present invention can promote the systematic treatment of gangue without lifting it to the ground. This method can effectively reduce transportation costs and reduce the impact on the surface environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present application 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 recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0044] Figure 1 This is a schematic diagram of the three-dimensional structure of the filling pile forming control system in the coal gangue goaf area.

[0045] Figure 2 Schematic diagram of the adhesive pipeline.

[0046] in:

[0047] 1. Roof rock layer; 2. Bottom rock layer; 3. Transfer conveyor; 4. Belt conveyor; 5. Fly ash silo; 6. Binder pipeline; 7. Double-roller sand making machine; 8. Multi-stage crushing mechanism; 9. Sorting chamber; 10. Gangue belt; 11. Spraying mechanism; 12. Binder; 13. Coal-gangue mixture; 14. Coal-gangue based self-stabilizing functional filling material; 15. Drum crusher; 16. Preparation chamber. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0049] The present invention provides Figure 1-2 A control system for forming a filling pile in a coal gangue goaf area shown in the figure comprises:

[0050] A fly ash silo 5 for storing fly ash;

[0051] An underground preparation assembly for processing a coal gangue mixture 13, comprising a screening table and a multi-stage crushing mechanism 8, wherein the screening table and the multi-stage crushing mechanism 8 respectively screen and crush the filling raw materials into a target particle size, wherein the multi-stage crushing mechanism 8 comprises a drum crusher 15 and a double-roller sand making machine 7;

[0052] A filling material conveying assembly for conveying materials, comprising a transfer conveyor 3, a belt conveyor 4 and a gangue belt 10, wherein the gangue belt 10 is located between the output end of the screening table and the input end of the drum crusher 15, the belt conveyor 4 receives materials from the fly ash bin 5, the roller sand making machine 7 and the drum crusher 15 through the conveyor belt, the output end of the belt conveyor 4 is connected to the input end of the transfer conveyor 3, and the output end of the transfer conveyor 3 extends to the area to be filled;

[0053] The binder spraying mechanism for modifying the coal gangue mixture 13 comprises a binder pipeline 6, at the bottom of which a sprayer 11 is arranged, wherein a binder 12 is transported inside the binder pipeline 6 and sprayed on the coal gangue mixture 13 through the sprayer 11 to generate a coal gangue-based functional filling material 14.

[0054] Preferably, the filling pile of the coal gangue goaf is located in the tunnel between the roof rock layer 1 and the floor rock layer 2, and a sorting chamber 9 and a preparation chamber 16 are reserved in the tunnel;

[0055] A passage runs through the sorting chamber 9 and the preparation chamber 16, and the gangue belt 10 is arranged along the passage.

[0056] Specifically, in the above technical solution, the screening platform is arranged in the sorting chamber 9, and the fly ash bin 5, the drum crusher 15 and the double-roller sand making machine 7 are all arranged in the preparation chamber 16.

[0057] Specifically, in the above technical solution, a material distribution table is provided at the output end of the drum crusher 15, and the output end of the material distribution table is respectively connected to the belt conveyor 4 and the roller sand making machine 7 through two conveyor belts; the drum crusher 15 and the roller sand making machine 7 respectively perform preliminary crushing and secondary crushing of the conveyed gangue.

[0058] Specifically, in the above technical solution, the adhesive pipeline 6 extends from the well to the inside of the preparation chamber 16, and the adhesive pipeline 6 is arranged along the direction of the belt conveyor 4 and installed directly above the belt conveyor 4. The vertical distance between the adhesive pipeline 6 and the belt conveyor 4 is set to 1.5m.

[0059] Specifically, in the above technical solution, the sprayer 11 includes a spray pipe and a spray head, and the top end and the bottom end of the spray pipe are respectively connected to the adhesive pipeline 6 and the spray head.

[0060] Specifically, in the above technical solution, the number of the sprayers 11 is set to be multiple, and the multiple sprayers 11 are distributed in a linear array along the direction of the adhesive pipeline 6, and the interval length between two adjacent sprayers 11 is D, in meters, and the calculation formula is as follows:

[0061] D=2(1+δ)R

[0062] In the formula, δ is the surplus coefficient, which is determined by experience;

[0063] R is the spray radius of the sprayer 11 for the belt conveyor 4, and the unit is m.

[0064] In the embodiment of the present invention, the spray radius of the sprayer 11 for the belt conveyor 4 is set to 1 m, the value of δ is 0.15, and D is calculated to be 2.3 m by substituting it into the above expression.

[0065] A method for controlling the formation of a filling pile in a gangue goaf area adopts the above-mentioned control system for forming a filling pile in a gangue goaf area to perform operations, and comprises the following steps:

[0066] S1. Determine the required compressive strength of the filling body of the goaf, and select the optimal ratio of the coal gangue mixture 13 according to the required compressive strength, so that the compressive strength requirement can be met and the modified coal gangue content is the lowest;

[0067] The total amount of fly ash and gangue is set as follows by mass ratio:

[0068] Gangue accounts for 75-85%;

[0069] Fly ash accounts for 15-25%;

[0070] The mass ratio of modified coal gangue to ordinary gangue in the total amount of gangue is set to 1:1.

[0071] The process of determining the optimal ratio is as follows:

[0072] S1.1. Determine the required compressive strength of the filling body in the goaf by combining field measurement with numerical simulation;

[0073] S1.2. According to laboratory tests, the dosage of modified coal gangue, ordinary gangue and fly ash was studied, and the strength of the filling material under different modified coal gangue ratio conditions was measured;

[0074] S1.3. In the results of S1.2, the optimal mix ratio is selected as the one that meets the compressive strength requirements and has the lowest modified gangue content;

[0075] S2. Design underground preparation components according to the underground mine layout. The process is as follows:

[0076] S2.1. Considering the system connection layout, a sorting chamber 9 and a preparation chamber 16 are constructed in the tunnel between the roof rock layer 1 and the floor rock layer 2, and a gangue storage bin is constructed near the sorting chamber 9;

[0077] S2.2, install a screening table in the sorting chamber 9, install a fly ash bin 5, a drum crusher 15, a material distribution table and a roller sand making machine 7 in the preparation chamber 16, and connect the screening table, fly ash bin 5, drum crusher 15, material distribution table and roller sand making machine 7 to each other through a filling material conveying component to form a filling pile forming system integrating processing and conveying;

[0078] S2.3, arranging an adhesive pipeline 6 with a sprayer 11 along the direction of the belt conveyor 4;

[0079] S3, screening and transporting the gangue underground, using the drum crusher 15 and the roller sand making machine 7 to initially crush the gangue, and transporting a portion of it directly to the belt conveyor 4 according to the proportion as ordinary gangue; the other portion is transported to the roller sand making machine 7 for further crushing, and the gangue is modified by the action of high-energy mechanical force, and the gangue passing through the roller sand making machine 7 is processed into modified gangue;

[0080] S4, mixing the modified coal gangue, ordinary gangue and fly ash according to the proportion obtained in S1 to form a coal gangue mixture 13;

[0081] S5, conveying the binder 12 through the binder pipeline 6, and spraying it evenly from the sprayer 11 to the coal gangue mixture 13, forming a 3-5 mm covering layer on its surface, and forming a coal gangue-based functional filling material 14 after mixing. The material has a self-stabilizing mechanism and is conveyed to the working surface of the filling area through the transfer conveyor 3 for filling;

[0082] The binder 12 used in this embodiment includes, by weight, 20 parts of cement, 2 parts of cement early strength activator, 3 parts of accelerating agent and 75 parts of water.

[0083] In specific applications, according to the actual conditions of a mine, the required compressive strength of the backfill of the goaf is determined to be 10MPa. According to laboratory tests, the dosage of modified gangue, ordinary gangue and fly ash is studied, and the strength of the backfill material under different modified gangue ratios is measured. The modified gangue, ordinary gangue and fly ash ratio is best when the gangue accounts for 80% and the fly ash accounts for 20%.

[0084] Gangue-based self-stabilizing functional filling materials with modified gangue in different proportions were prepared and their uniaxial compressive strength was tested. The different test schemes and results are shown in Table 1.

[0085] Table 1 Strength parameters of gangue-based self-stabilizing functional filling materials made with different modified gangue ratios

[0086]

[0087]

[0088] In order to reduce the time cost of modification, the ratio that meets the compressive strength requirements and has the lowest modified gangue content is selected as the optimal ratio, that is, the mass ratios of modified gangue, ordinary gangue and fly ash are 35%, 35% and 20% respectively, that is, 50% of the gangue needs mechanical modification.

[0089] After the underground coal gangue is sorted and crushed, 50% is directly transported to the belt conveyor 4 according to the ratio, and 50% is transported to the roller sand making machine 7 for further crushing to less than 2 mm, and the coal gangue is modified by high-energy mechanical force.

[0090] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A control system for forming a filling pile in a coal gangue goaf, characterized in that: include: A fly ash silo (5) for storing fly ash; An underground preparation assembly for processing a coal gangue mixture (13), comprising a screening table and a multi-stage crushing mechanism (8), wherein the screening table and the multi-stage crushing mechanism (8) respectively screen and crush the filling raw materials into a target particle size, wherein the multi-stage crushing mechanism (8) comprises a drum crusher (15) and a double-roller sand making machine (7); A filling material conveying assembly for conveying materials, comprising a transfer conveyor (3), a belt conveyor (4) and a gangue belt (10), wherein the gangue belt (10) is located between the output end of the screening table and the input end of the drum crusher (15), the belt conveyor (4) receives materials from the fly ash bin (5), the roller sand making machine (7) and the drum crusher (15) through the conveyor belt, the output end of the belt conveyor (4) is connected to the input end of the transfer conveyor (3), and the output end of the transfer conveyor (3) extends to the area to be filled; A binder spraying mechanism for modifying a coal gangue mixture (13) comprises a binder pipeline (6), a sprayer (11) being arranged at the bottom of the binder pipeline (6), wherein a binder (12) is transported inside the binder pipeline and sprayed onto the coal gangue mixture (13) through the sprayer (11), thereby generating a coal gangue-based functional filling material (14).

2. A control system for forming a filling pile in a gangue goaf area according to claim 1, characterized in that: The filling pile of the coal gangue goaf is located in a tunnel between the roof rock layer (1) and the floor rock layer (2), and a separation chamber (9) and a preparation chamber (16) are reserved in the tunnel; A passage runs through the separation chamber (9) and the preparation chamber (16), and a gangue belt (10) is arranged along the passage.

3. A control system for forming a filling pile in a gangue goaf area according to claim 2, characterized in that: The screening platform is arranged in the sorting chamber (9), and the fly ash bin (5), the drum crusher (15) and the double-roller sand making machine (7) are all arranged in the preparation chamber (16).

4. A control system for forming a filling pile in a gangue goaf area according to claim 3, characterized in that: The output end of the drum crusher (15) is provided with a material distribution table, and the output end of the material distribution table is respectively connected to a belt conveyor (4) and a roller sand making machine (7) through two conveyor belts; the drum crusher (15) and the roller sand making machine (7) respectively perform preliminary crushing and secondary crushing on the transported gangue.

5. A control system for forming a filling pile in a gangue goaf area according to claim 2, characterized in that: The adhesive pipeline (6) extends from the well to the inside of the preparation chamber (16), and the adhesive pipeline (6) is arranged along the direction of the belt conveyor (4) and installed directly above the belt conveyor (4). The vertical distance between the adhesive pipeline (6) and the belt conveyor (4) is set to 1.5m.

6. A control system for forming a filling pile in a gangue goaf area according to claim 2, characterized in that: The sprayer (11) comprises a spray pipe and a spray head, and the top end and the bottom end of the spray pipe are respectively connected to the adhesive pipeline (6) and the spray head.

7. A control system for forming a filling pile in a gangue goaf area according to claim 1, characterized in that: The number of the sprayers (11) is set to be multiple, and the multiple sprayers (11) are distributed in a linear array along the direction of the adhesive pipeline (6), and the interval length between two adjacent sprayers (11) is D, which is calculated as follows: D=2(1+δ)R In the formula, δ is the surplus coefficient, which is determined by experience; R is the spray radius of the sprayer (11) with respect to the belt conveyor (4).

8. A method for controlling the formation of a filling pile in a gangue goaf area, using the gangue goaf area filling pile formation control system as claimed in any one of claims 1 to 7 for operation, characterized in that: The following steps are involved: S1. Determine the required compressive strength of the filling body of the goaf, and select the optimal ratio of the coal gangue mixture (13) according to the required compressive strength. The process is as follows: S1.

1. Determine the required compressive strength of the filling body in the goaf by combining field measurement with numerical simulation; S1.

2. According to laboratory tests, the dosage of modified coal gangue, ordinary gangue and fly ash was studied, and the strength of the filling material under different modified coal gangue ratio conditions was measured; S1.

3. In the results of S1.2, the optimal mix ratio is selected as the one that meets the compressive strength requirements and has the lowest modified gangue content; S2. Design underground preparation components according to the underground mine layout. The process is as follows: S2.

1. Constructing a sorting chamber (9) and a preparation chamber (16) in the tunnel between the roof rock layer (1) and the floor rock layer (2), and constructing a gangue storage bin near the sorting chamber (9); S2.2, installing a screening table in the sorting chamber (9), installing a fly ash bin (5), a drum crusher (15), a material distribution table and a roller sand making machine (7) in the preparation chamber (16), and connecting the screening table, the fly ash bin (5), the drum crusher (15), the material distribution table and the roller sand making machine (7) to each other through a filling material conveying component, so as to form a filling pile forming system integrating processing and conveying; S2.3, arranging an adhesive pipeline (6) with a sprayer (11) along the direction of the belt conveyor (4); S3, screening and transporting the gangue underground, using a drum crusher (15) and a roller sand making machine (7) to preliminarily crush the gangue, and transporting a portion of the gangue directly to the belt conveyor (4) according to the proportion as ordinary gangue; the other portion is transported to the roller sand making machine (7) for further crushing, and the gangue is modified by high-energy mechanical force, and the gangue passing through the roller sand making machine (7) is processed into modified gangue; S4, mixing the modified coal gangue, ordinary gangue and fly ash according to the proportion obtained in S1 to form a coal gangue mixture (13); S5. The binder (12) is transported through the binder pipeline (6) and sprayed evenly onto the coal gangue mixture (13) from the sprayer (11) to form a covering layer of 3-5 mm on its surface. After mixing, a coal gangue-based functional filling material (14) is formed and sent to the working surface of the filling area through the transfer conveyor (3) for filling.

9. A method for controlling the formation of a filling pile in a gangue goaf area according to claim 8, characterized in that: In S1, the total amount of fly ash and gangue is set to be: Gangue accounts for 75-85%; Fly ash accounts for 15-25%; The mass ratio of the modified coal gangue to the ordinary gangue in the total amount of gangue is set to 1:

1.

10. A method for controlling the formation of a filling pile in a gangue goaf area according to claim 8, characterized in that: The binder (12) comprises, by weight, 20 parts of cement, 2 parts of cement early strength activator, 3 parts of accelerating agent and 75 parts of water.

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