Coal gangue goaf filling heap body forming control system and method

Abstract

The present application relates to a kind of coal gangue goaf filling heap body forming control system and method, system includes fly ash bin, underground preparation component, filling material conveying component and binder spraying mechanism.Underground preparation component includes screening table and multistage crushing mechanism.The present application is crushed to coal gangue twice, so that the particle size distribution of solid filling material is smaller, it is not easy to chain card in the scraper conveyor at working face, it is convenient to transport, improves the stability of transportation.By the method of spraying binder on solid filling material, improve the consolidation between solid material, realize the preparation of coal gangue base self-stable type function filling material, it can reduce or avoid material back sliding in the process of filling ramming, thereby reducing ramming frequency, improve filling efficiency.Coal gangue goaf filling heap body forming control method is safe and reliable, easy to use, strong applicability, not only can efficiently handle solid waste gangue, but also can fill part of goaf, relieve working face mine pressure appearance phenomenon.

Description

Technical Field

[0001] This invention relates to the field of gangue backfilling materials technology, specifically a control system and method for forming a coal gangue goaf backfill stockpile. Background Technology

[0002] Solid backfilling mining technology involves using backfilling materials such as gangue to backfill mined-out areas. This not only helps to obtain coal resources, but also effectively prevents the collapse of the mined-out area and actively protects the ecological environment.

[0003] In existing solid backfill mining technology, after solid materials are transported to the goaf, they need to be compacted by a hydraulic support to shape the loose solid backfill material. However, ordinary solid materials will slip back after compaction, so multiple compactions are required to achieve the ideal filling rate, which restricts the improvement of solid backfill mining efficiency.

[0004] To address the aforementioned technical issues, it is essential to develop a control system and method for the formation of coal gangue goaf filling stockpiles. Summary of the Invention

[0005] The purpose of this invention is to address the problems existing in the prior art by providing a simple, safe, and efficient control system and method for forming coal gangue goaf backfill stockpile. By secondary crushing of the coal gangue, the particle size distribution of the solid backfill material is made smaller, making it less prone to chain jamming at the scraper conveyor at the working face and facilitating transportation. Furthermore, the design uses a binder sprayed on the solid backfill material to improve the bonding performance between the backfill materials, enhance the self-stability of the backfill stockpile, form a coal gangue-based self-stabilizing functional backfill material, and reduce the number of compaction cycles.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A coal gangue goaf backfill stockpile forming control system, comprising:

[0008] Fly ash silos are used to store fly ash.

[0009] An underground preparation assembly for processing coal gangue mixtures includes a screening table and a multi-stage crushing mechanism. The screening table and the multi-stage crushing mechanism respectively screen and crush the raw materials for backfilling into the target particle size. The multi-stage crushing mechanism includes a drum crusher and a double-roll sand making machine.

[0010] A filling material conveying assembly for conveying materials includes 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 silo, the double roller sand making machine, and the drum crusher via 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] A binder spraying mechanism for modifying coal gangue mixtures includes a binder pipeline with a sprayer at the bottom of the binder pipeline. The binder is transported inside the pipeline and sprayed onto the coal gangue mixture through the sprayer to generate coal gangue-based functional filling material.

[0012] Preferably, the coal gangue goaf filling stockpile is located in the roadway between the roof strata and the floor strata, and the roadway is reserved with sorting chambers and preparation chambers;

[0013] A passage runs through the sorting chamber and the preparation chamber, and the gangue conveyor belt is laid along the passage.

[0014] Preferably, the screening table is arranged in the sorting chamber, while the fly ash silo, drum crusher, and double-roll sand making machine are all arranged in the preparation chamber.

[0015] Preferably, the output end of the drum crusher is provided with a distribution platform, and the output end of the distribution platform is connected to a belt conveyor and a double-roll sand making machine respectively through two conveyor belts; the drum crusher and the double-roll sand making machine respectively perform primary crushing and secondary crushing of the conveyed gangue.

[0016] Preferably, the adhesive pipeline extends from the wellhead into 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 includes a spray pipe and a nozzle, with the top and bottom ends of the spray pipe connected to an adhesive pipeline and the nozzle, respectively.

[0018] Preferably, the number of sprayers is set to 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 by the following formula:

[0019] D=2(1+δ)R

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

[0021] R is the spray radius of the sprayer on the belt conveyor.

[0022] A method for controlling the formation of coal gangue goaf backfill stockpile, employing the aforementioned coal gangue goaf backfill stockpile formation control system, includes the following steps:

[0023] S1. Determine the required compressive strength of the goaf filling material, and select the optimal mix ratio of coal and gangue mixture based on the required compressive strength. The process is as follows:

[0024] S1.1 Determine the required compressive strength of the goaf filling body by combining on-site measurement and numerical simulation;

[0025] S1.2. Based on laboratory tests, the content of modified coal gangue, ordinary gangue and fly ash was studied, and the strength of the backfill material under different modified coal gangue ratios was measured.

[0026] S1.3. From the results of S1.2, select the ratio that meets the compressive strength requirements and has the lowest modified coal gangue content as the optimal ratio;

[0027] S2. Based on the underground layout of the mine, design the underground fabrication components. The process is as follows:

[0028] S2.1 Construct a sorting chamber and a preparation chamber in the roadway between the roof strata and the floor strata, and construct a gangue storage silo near the sorting chamber;

[0029] S2.2 Install a screening platform in the sorting chamber, and install a fly ash silo, a drum crusher, a distribution platform and a double roller sand making machine in the preparation chamber. Connect the screening platform, fly ash silo, drum crusher, distribution platform and double roller sand making machine to each other through the filling material conveying assembly to form a filling and conveying integrated filling and stacking forming system.

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

[0031] S3. Screening and underground conveying of gangue. The gangue is initially crushed using a drum crusher and a roller sand making machine. A portion is directly transported to a belt conveyor as ordinary gangue according to the proportion; the other portion is transported to a roller sand making machine for further crushing. The gangue is modified by high-energy mechanical force, and the gangue passing through the roller sand making machine is processed into modified coal gangue.

[0032] S4. Mix the modified coal gangue, ordinary gangue and fly ash according to the proportions 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 sprayer to form a 3-5mm covering layer on its surface. After mixing, it forms a coal gangue-based functional backfill material, which is then transported to the working face of the area to be filled by a transfer conveyor.

[0034] Preferably, in S1, the total amount of fly ash and gangue is set according to the following mass ratio:

[0035] Gangue accounts for 75-85%;

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

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

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

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

[0040] 1. By spraying a binder onto the solid backfill material, the cohesion between solid materials is improved, enabling the preparation of a self-stabilizing functional backfill material based on coal gangue. This method reduces or prevents material slippage during the backfilling and compaction process, thereby reducing the number of compaction cycles and improving backfilling efficiency. This method is safe, reliable, easy to use, and highly applicable. It can not only efficiently process solid waste gangue but also fill part of the goaf, alleviating the mining pressure manifestation phenomenon at the working face.

[0041] 2. The particle size distribution of solid materials has a significant impact on transportation efficiency. This invention, through secondary crushing of coal gangue, results in a smaller particle size distribution of the solid backfill material, reducing the likelihood of chain jamming at the scraper conveyor at the working face and facilitating transportation. This improves transportation stability, reduces downtime caused by chain jamming, and enhances overall operational efficiency. This invention is of great significance for large-scale gangue processing and improving solid backfill efficiency.

[0042] 3. Underground treatment of gangue is a crucial step in improving resource utilization and reducing environmental impact. The application of this invention facilitates the systematic treatment of gangue without bringing it to the surface. This method effectively reduces transportation costs and minimizes the impact on the surface environment. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0044] Figure 1 A schematic diagram of the three-dimensional structure of the control system for forming the filling stockpile in the goaf of coal gangue.

[0045] Figure 2 This is a schematic diagram of the adhesive piping.

[0046] in:

[0047] 1. Roof strata; 2. Floor strata; 3. Transfer conveyor; 4. Belt conveyor; 5. Fly ash silo; 6. Binder pipeline; 7. Roller crusher; 8. Multi-stage crushing mechanism; 9. Sorting chamber; 10. Gangue belt conveyor; 11. Spraying mechanism; 12. Binder; 13. Coal and gangue mixture; 14. Coal gangue-based self-stabilizing functional filling material; 15. Drum crusher; 16. Preparation chamber. Detailed Implementation

[0048] 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] This invention provides, for example Figure 1-2 The control system for forming a coal gangue goaf backfill stockpile, as shown, includes:

[0050] 5. Fly ash silo for storing fly ash;

[0051] The underground preparation assembly for processing coal gangue mixture 13 includes a screening table and a multi-stage crushing mechanism 8. The screening table and the multi-stage crushing mechanism 8 respectively screen and crush the raw materials for backfilling into the target particle size. The multi-stage crushing mechanism 8 includes a drum crusher 15 and a double-roll sand making machine 7.

[0052] The filling material conveying assembly for conveying materials includes 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 silo 5, the double roller sand making machine 7, and the drum crusher 15 via 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] A binder spraying mechanism for modifying coal gangue mixture 13 includes a binder pipeline 6, with a sprayer 11 at the bottom of the binder pipeline 6. The binder 12 is transported inside the pipeline and sprayed onto the coal gangue mixture 13 through the sprayer 11 to generate coal gangue-based functional filling material 14.

[0054] Preferably, the coal gangue goaf filling stockpile is located in the roadway 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 roadway;

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

[0056] Specifically, in the above technical solution, the screening table is arranged in the sorting chamber 9, and the fly ash silo 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, the output end of the drum crusher 15 is equipped with a distribution platform, and the output end of the distribution platform is connected to the belt conveyor 4 and the roller sand making machine 7 respectively through two conveyor belts; the drum crusher 15 and the roller sand making machine 7 respectively perform primary crushing and secondary crushing of the conveyed gangue.

[0058] Specifically, in the above technical solution, the binder pipeline 6 extends from the surface to the interior of the preparation chamber 16, and the binder 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 binder 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 nozzle, with the top and bottom ends of the spray pipe connected to the adhesive pipeline 6 and the nozzle, respectively.

[0060] Specifically, in the above technical solution, the number of sprayers 11 is set to 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, with the unit being meters, and its calculation formula is as follows:

[0061] D=2(1+δ)R

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

[0063] R is the spray radius of sprayer 11 for belt conveyor 4, in meters.

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

[0065] A method for controlling the formation of coal gangue goaf backfill stockpile, employing the coal gangue goaf backfill stockpile formation control system as described above, includes the following steps:

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

[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 gangue is set to 1:1.

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

[0072] S1.1 Determine the required compressive strength of the goaf filling body by combining on-site measurement and numerical simulation;

[0073] S1.2. Based on laboratory tests, the content of modified coal gangue, ordinary gangue and fly ash was studied, and the strength of the backfill material under different modified coal gangue ratios was measured.

[0074] S1.3. From the results of S1.2, select the ratio that meets the compressive strength requirements and has the lowest modified coal gangue content as the optimal ratio;

[0075] S2. Based on the underground layout of the mine, design the underground fabrication components. The process is as follows:

[0076] S2.1 Considering the system connection and layout, a sorting chamber 9 and a preparation chamber 16 are constructed in the roadway between the top rock layer 1 and the bottom rock layer 2, and a gangue storage silo is built near the sorting chamber 9.

[0077] S2.2 Install a screening platform in the sorting chamber 9, and install a fly ash silo 5, a drum crusher 15, a distribution platform and a double roller sand making machine 7 in the preparation chamber 16. Connect the screening platform, fly ash silo 5, drum crusher 15, distribution platform and double roller sand making machine 7 to each other through the filling material conveying assembly to form a filling and stacking body forming system that integrates processing and conveying.

[0078] S2.3. An adhesive pipeline 6 with a sprayer 11 is arranged along the direction of the belt conveyor 4.

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

[0080] S4. Mix the modified coal gangue, ordinary gangue and fly ash according to the proportions obtained in S1 to form a coal gangue mixture 13.

[0081] S5. The binder 12 is delivered through the binder pipeline 6 and sprayed evenly from the sprayer 11 onto the coal gangue mixture 13 to form a 3-5mm covering layer on its surface. After mixing, the coal gangue-based functional filling material 14 is formed. This material has a self-stabilizing mechanism and is sent to the working face of the area to be filled by the transfer conveyor 3.

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

[0083] In practical applications, based on the actual conditions of a certain mine, the required compressive strength of the goaf filling body was determined to be 10 MPa. Based on laboratory tests, the admixture of modified coal gangue, ordinary gangue and fly ash was studied, and the strength of the filling material under different modified coal gangue ratios was measured. The optimal ratio of modified coal gangue, ordinary gangue and fly ash was found to be 80% gangue and 20% fly ash.

[0084] Coal gangue-based self-stabilizing functional filling materials with different proportions of modified coal gangue 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 coal gangue-based self-stabilizing functional backfill materials prepared with different modified coal gangue proportions.

[0086]

[0087]

[0088] To reduce the time and cost of modification, the optimal ratio is selected as the ratio that meets the compressive strength requirements and has the lowest modified coal gangue content. That is, the mass ratio of modified coal gangue, ordinary gangue and fly ash is 35%, 35% and 20% respectively, meaning that 50% of the coal gangue needs mechanical modification treatment.

[0089] After underground coal gangue is sorted and crushed, 50% is directly transported to belt conveyor 4 and 50% is transported to roller crusher 7 for further crushing to below 2mm. The coal gangue is modified by high-energy mechanical force.

[0090] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, 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 foregoing 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 the forming of coal gangue goaf backfill stockpile, characterized in that, include: Fly ash silos used for storing fly ash (5); The underground preparation assembly for processing coal gangue mixture (13) includes a screening table and a multi-stage crushing mechanism (8), which respectively screen and crush the raw materials for filling into the target particle size. The multi-stage crushing mechanism (8) includes a drum crusher (15) and a double-roll sand making machine (7). The filling material conveying assembly for conveying materials includes 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 silo (5), the double roller sand making machine (7), and the drum crusher (15) via 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 filling area; A binder spraying mechanism for modifying coal gangue mixture (13) includes a binder pipeline (6), with a sprayer (11) at the bottom of the binder pipeline (6), which transports binder (12) and sprays it onto the coal gangue mixture (13) through the sprayer (11) to generate coal gangue-based functional filling material (14). The gangue is screened and transported underground. The gangue is initially crushed using a roller crusher (15) and a double-roller sand making machine (7). A portion is directly transported to a belt conveyor (4) as ordinary gangue, while the other portion is transported to the double-roller sand making machine (7) for further crushing. The gangue is modified by high-energy mechanical force, and the gangue passed through the double-roller sand making machine (7) is processed into modified coal gangue. The modified coal gangue, ordinary gangue and fly ash are mixed according to the proportion to form a coal gangue mixture (13).

2. The coal gangue goaf filling stock formation control system according to claim 1, characterized in that, The coal gangue goaf filling stockpile is located in the roadway 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 roadway. A channel runs through the sorting chamber (9) and the preparation chamber (16), and the gangue belt (10) is laid along the channel.

3. The coal gangue goaf filling stock formation control system according to claim 2, characterized in that, The screening platform is arranged in the sorting chamber (9), and the fly ash silo (5), the drum crusher (15) and the double roller sand making machine (7) are all arranged in the preparation chamber (16).

4. The coal gangue goaf filling stock formation control system according to claim 3, characterized in that, The output end of the drum crusher (15) is equipped with a material distribution platform, and the output end of the material distribution platform is connected to the belt conveyor (4) and the double roller sand making machine (7) respectively through two conveyor belts; the drum crusher (15) and the double roller sand making machine (7) respectively perform preliminary crushing and secondary crushing of the conveyed gangue.

5. A coal gangue goaf filling stock formation control system according to claim 2, characterized in that, The adhesive pipeline (6) extends from the wellhead to the interior 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 coal gangue goaf filling stock formation control system according to claim 2, characterized in that, The sprayer (11) includes a spray pipe and a nozzle, with the top and bottom ends of the spray pipe connected to the adhesive pipeline (6) and the nozzle, respectively.

7. A coal gangue goaf filling and stockpile forming control system according to claim 1, characterized in that, The number of sprayers (11) is set to 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 by the following formula: ， In the formula, δ is the surplus coefficient, which is determined empirically; R is the spray radius of the sprayer (11) for the belt conveyor (4).

8. A method for controlling the formation of a coal gangue goaf backfill stockpile, comprising using the coal gangue goaf backfill stockpile formation control system as described in any one of claims 1-7, characterized in that, Includes the following steps: S1. Determine the required compressive strength of the goaf filling body, and select the optimal proportion of coal gangue mixture (13) according to the required compressive strength. The process is as follows: S1.1 Determine the required compressive strength of the goaf filling body by combining on-site measurements and numerical simulation; S1.

2. Based on laboratory tests, the content of modified coal gangue, ordinary gangue and fly ash was studied, and the strength of the backfill material under different modified coal gangue ratios was measured. S1.

3. From the results of S1.2, select the ratio that meets the compressive strength requirements and has the lowest modified coal gangue content as the optimal ratio; S2. Based on the underground layout of the mine, design the underground fabrication components. The process is as follows: S2.1 Construct a sorting chamber (9) and a preparation chamber (16) in the tunnel between the top stratum (1) and the bottom stratum (2), and construct a gangue storage silo near the sorting chamber (9); S2.2 Install a screening platform in the sorting chamber (9), and install a fly ash silo (5), a drum crusher (15), a distribution platform and a double roller sand making machine (7) in the preparation chamber (16). Connect the screening platform, fly ash silo (5), drum crusher (15), distribution platform and double roller sand making machine (7) to each other through the filling material conveying assembly to form a filling and conveying integrated filling and stacking body forming system. S2.

3. Arrange adhesive pipelines (6) with sprayers (11) along the direction of the belt conveyor (4). S3. Screen and transport gangue underground. Use a drum crusher (15) and a double-roll sand making machine (7) to initially crush the gangue. According to the proportion, a portion is directly transported to the belt conveyor (4) as ordinary gangue; the other portion is transported to the double-roll sand making machine (7) for further crushing. The gangue is modified by high-energy mechanical force, and the gangue passed through the double-roll sand making machine (7) is processed into modified coal gangue. S4. Mix the modified coal gangue, ordinary gangue and fly ash according to the proportions obtained in S1 to form a coal gangue mixture (13). S5. The binder (12) is transported through the binder pipeline (6) and sprayed evenly from the sprayer (11) onto the coal gangue mixture (13) to form a 3-5 mm covering layer on its surface. After mixing, the coal gangue-based functional filling material (14) is formed and sent to the working face of the area to be filled by the transfer conveyor (3).

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

1.

10. A method for controlling the formation of a coal gangue goaf backfill body 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 quick-setting agent and 75 parts of water.

Images