An efficient filling mining method based on gangue-cemented highly porous materials

Abstract

The present invention discloses an efficient filling mining method based on gangue-cemented highly porous materials. By using a post-supporter spraying system to spray a fast-setting material to form gangue-cemented highly porous materials together with gangue, an efficient filling mining technology for self-expanding roof contact of filling materials is realized, solving the problems of insufficient gangue materials required for large-scale filling and low filling efficiency, including an efficient filling mining process and a method for controlling the shape of the filling heap. In the efficient filling mining process, the blanking process and the spraying process are executed synchronously, and the support moving process lags behind. The method for controlling the shape of the filling heap is to control the blanking speed, spraying speed, spraying pressure, spraying angle, and spraying rotation speed according to the height of the filling heap, thereby controlling the shape of the filling heap. The present invention can control the movement of the roof rock stratum of the working face while breaking through the problems of filling mining efficiency and insufficient gangue materials. The method is simple and efficient, and the working process is safe.

Description

Technical Field

[0001] The present invention relates to the field of filling mining, and particularly to an efficient filling mining method based on gangue-cemented highly porous materials. Background Art

[0002] The filling mining technology is an important representative technology for realizing green and low-carbon mining, and has significant technical advantages in aspects such as surface subsidence control, ecological environment protection, disposal and utilization of mine solid wastes, and green and low-carbon emission reduction. The coal industry promotes "underground filling of coal gangue + surface backfilling" to reduce the amount of gangue, and establishes a "cascaded recovery + ecological restoration + sealed protection" system to promote the construction of green mines. However, efficiency problems such as the impact of filling operations on coal mining speed, coal output, coal production benefits, and insufficient raw material volume of large-scale filling gangue restrict the further popularization and application of the filling mining technology. It is urgent to solve the efficiency problem of filling mining. Summary of the Invention

[0003] Aiming at the above-mentioned existing technical deficiencies, the purpose of the present invention is to provide an efficient filling mining method based on gangue-cemented highly porous materials, which is simple, safe in the working process, efficient, and has high economic benefits.

[0004] To solve the above technical problems, the present invention adopts the following technical solutions:

[0005] The present invention provides an efficient filling mining method based on gangue-cemented highly porous materials, including:

[0006] An efficient filling mining process; the highly porous materials are dropped into the goaf through a multi-hole bottom-discharge scraper conveyor arranged on the hydraulic support. During the dropping process of the highly porous materials, a preset injection system sprays a fast-setting slurry to cement the highly porous material heap into shape;

[0007] A method for controlling the shape of the filling heap; the dropping speed, spraying speed, spraying pressure, spraying angle, and spraying rotation speed are controlled according to the height of the filling heap, so as to control the shape of the filling heap;

[0008] The efficient filling mining process and the method for controlling the shape of the filling heap cooperate to achieve the purpose of self-expanding and roof-connecting high-efficiency filling mining of the filling materials.

[0009] Preferably, the efficient filling mining process specifically includes;

[0010] A dropping process; the highly porous materials fall into the goaf behind the support in the filling working face through the multi-hole bottom-discharge scraper conveyor, and the dropping speed is controlled by controlling the size of the discharge opening of the multi-hole bottom-discharge scraper conveyor;

[0011] Shotcreting process: The fast-setting slurry is injected through the post-mounted injection system while the material is being dropped. The fast-setting slurry rapidly expands between the naturally piled high-porosity materials and generates a setting effect, forming a filling body with a certain strength, namely gangue-cemented high-porosity materials.

[0012] Supporter moving process: When the filling material of the filling body self-expands and touches the roof, and the filling heap touches the roof, the material dropping stops. When the size of the filling body in the working face advancing direction reaches the pushing step distance, the hydraulic support starts to move the supporter.

[0013] The material dropping process and the shotcreting process are carried out synchronously, and the supporter moving process lags behind the material dropping process and the shotcreting process.

[0014] Preferably, the method for controlling the shape of the filling heap specifically includes:

[0015] S31. When the height of the filling heap is less than or equal to 0.5 times the mining height, the material dropping speed, the shotcreting volume, the shotcreting pressure, and the shotcreting rotation speed are the rated amounts. The rated amounts are the standard amounts, which are specifically determined jointly according to the filling space, the gangue treatment requirements, etc. The maximum shotcreting angle increases in real time following the dropping height. During the material dropping process, shotcreting continues and cycles from the minimum shotcreting angle to the maximum shotcreting angle.

[0016] S32. When the height of the filling heap is greater than 0.5 times the mining height and less than 0.75 times the mining height, the material dropping speed drops to 0.75 times the rated amount, the shotcreting volume, the shotcreting pressure, and the shotcreting rotation speed are the rated amounts. The maximum shotcreting angle increases in real time following the dropping height. During the material dropping process, shotcreting continues and cycles from the minimum shotcreting angle to the maximum shotcreting angle.

[0017] S33. When the height of the filling heap is greater than 0.75 times the mining height, the material dropping speed drops to 0.5 times the rated amount, the shotcreting volume, the shotcreting pressure, and the shotcreting rotation speed increase to 1.25 - 1.5 times the rated amount. The maximum shotcreting angle increases in real time following the dropping height. During the material dropping process, shotcreting continues and cycles from the minimum shotcreting angle to the maximum shotcreting angle. When the filling heap touches the roof, the material dropping stops, and the shotcreting process lags behind the material dropping process by 3 - 5 minutes and then stops.

[0018] Preferably, the high-porosity material is selected as the bulk coal gangue material, and its porosity reaches more than 50%.

[0019] Preferably, the fast-setting slurry is selected from existing high-water rapid-setting materials, which are new cementitious materials of non-hydrophobic silicate type.

[0020] The beneficial effects of the present invention are as follows: This method is mainly applied to coal seam filling mining. While controlling the movement of the roof rock strata in the working face, it solves the problem of insufficient gangue filling materials in a large range through gangue-cemented high-porosity materials. The filling process is optimized, the filling mining efficiency is improved, the method is simple and efficient, the working process is safe, which is conducive to promoting the large-scale application of filling mining methods and has great popularization and application prospects, and its scientific and engineering significance is huge. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0022] Figure 1 It is a schematic diagram of non-compacted filling and stacking roof connection provided by an embodiment of the present invention;

[0023] Figure 2 It is a schematic diagram of the method for controlling the shape of the filling stack body when the height of the filling stack body is less than or equal to 0.5 times the mining height provided by an embodiment of the present invention;

[0024] Figure 3 It is a schematic diagram of the method for controlling the shape of the filling stack body when the height of the filling stack body is greater than or equal to 0.5 times the mining height provided by an embodiment of the present invention.

[0025] In the figure:

[0026] 1 - floor, 2 - gangue-cemented high-porosity material, 3 - roof, 4 - high-porosity material, 5 - multi-hole bottom-discharge scraper conveyor, 6 - fast-setting slurry, 7 - injection system, 8 - hydraulic support, 9 - shearer; DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0028] An embodiment of the present invention provides an efficient filling mining method based on gangue-cemented high-porosity materials, including:

[0029] High-efficiency filling mining technology; through the porous bottom-unloading scraper conveyor 5 on the hydraulic support 8 on the floor 1, the high-porosity material 4 is dropped into the goaf. The high-porosity material is selected as bulk coal gangue material, and its porosity reaches more than 50%. During the dropping process of the high-porosity material 4, the preset injection system 7 sprays the fast-setting slurry 6 to cement the high-porosity material 4 into a heap; the fast-setting slurry 6 used in this embodiment is selected from the existing high-water quick-setting materials, which are new cementitious materials of non-hydrophobic silicate type.

[0030] Filling heap form control method; control the dropping speed, spraying speed, spraying pressure, spraying angle and spraying rotation speed according to the height of the filling heap, so as to control the form of the filling heap;

[0031] The high-efficiency filling mining technology and the filling heap form control method cooperate to achieve the purpose of high-efficiency filling mining with self-expanding roof contact of the filling material.

[0032] The specific steps of the high-efficiency filling mining technology include:

[0033] Dropping process; the shearer 9 mines coal. During this period, the high-porosity material 4 falls into the goaf behind the support in the filling working face through the porous bottom-unloading scraper conveyor 5, and the dropping speed is controlled by adjusting the size of the discharge opening of the porous bottom-unloading scraper conveyor 5;

[0034] Spraying process; the fast-setting slurry 6 is sprayed through the post-support injection system 7 while dropping. The fast-setting slurry 6 expands rapidly and generates a coagulation effect among the naturally piled high-porosity materials 4 to form a filling body with a certain strength; the injection system 7 is selected from existing devices, such as the spraying device disclosed in the patent application "A Long-distance Continuous Spraying Device and Spraying Control Method for Underground Coal Mines" with the publication number CN113605936A, which can achieve controllable-angle spraying in the vertical direction;

[0035] Support moving process; after the filling body self-expands and contacts the roof, when the size of the filling body in the working face advancing direction reaches the pushing step distance, the hydraulic support 8 starts to move; See Figure 1 ;

[0036] The dropping process and the spraying process are carried out synchronously, and the support moving process lags behind the dropping process and the spraying process.

[0037] The specific steps of the filling heap form control method include:

[0038] S31. When the height of the filling heap is less than or equal to 0.5 times the mining height, the dropping speed, spraying volume, spraying pressure, and spraying rotation speed are rated values, the maximum spraying angle increases in real time following the dropping height, spraying is continuously carried out during the dropping process, and spraying is cycled from the minimum spraying angle to the maximum spraying angle; See Figure 2 ;

[0039] S32. When the filling heap height is greater than 0.5 times the mining height and less than 0.75 times the mining height, the blanking speed drops to 0.75 times the rated amount, the shotcrete volume, shotcrete pressure, and shotcrete rotation speed are the rated amounts, the maximum shotcrete angle increases in real time following the blanking height, shotcrete is continuously carried out during the blanking process and shotcrete is cycled from the minimum shotcrete angle to the maximum shotcrete angle;

[0040] S33. When the filling heap height is greater than 0.75 times the mining height, the blanking speed drops to 0.5 times the rated amount, the shotcrete volume, shotcrete pressure, and shotcrete rotation speed increase to 1.25 - 1.5 times the rated amount, the maximum shotcrete angle increases in real time following the blanking height, shotcrete is continuously carried out during the blanking process and shotcrete is cycled from the minimum shotcrete angle to the maximum shotcrete angle until the filling heap height is equal to the mining height, that is, when the filling heap contacts the roof 3, the blanking process is stopped, and the shotcrete process stops 3 - 5 minutes after the blanking process. See Figure 3 。

[0041] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these changes and modifications.

Claims

1. An efficient filling mining method based on gangue-cemented high-porosity materials, characterized in that, Including: High-efficiency filling mining technology; the high-porosity material (4) is dropped into the goaf through the porous bottom-unloading scraper conveyor (5) arranged on the hydraulic support (8). During the dropping process of the high-porosity material (4), the preset injection system (7) sprays out the quick-setting slurry (6) to cement the high-porosity material (4) to form the gangue-cemented high-porosity material (2); the quick-setting slurry (6) is selected from existing high-water quick-setting materials and is a new type of cementitious material that is non-hydrophobic silicate-based; The specific steps of the high-efficiency filling mining technology include: Dropping process; the high-porosity material (4) falls into the goaf behind the support in the filling working face through the porous bottom-unloading scraper conveyor (5), and the dropping speed is controlled by controlling the size of the discharge opening of the porous bottom-unloading scraper conveyor (5); Spraying process; the quick-setting slurry (6) is sprayed through the post-support injection system (7) while dropping. The quick-setting slurry (6) rapidly expands and produces a coagulation effect among the naturally accumulated high-porosity materials (4) to form a filling body with a certain strength; Support moving process; when the filling material of the filling body expands and touches the roof by itself and the filling heap touches the roof, the dropping stops; when the size of the filling body in the working face advancing direction reaches the pushing step distance, the hydraulic support (8) starts to move the support; The dropping process and the spraying process are carried out synchronously, and the support moving process lags behind the dropping process and the spraying process; Method for controlling the shape of the filling heap; according to the height of the filling heap, control the dropping speed, spraying speed, spraying pressure, spraying angle, and spraying rotation speed, so as to control the shape of the filling heap; The high-efficiency filling mining technology and the method for controlling the shape of the filling heap cooperate to achieve the purpose of high-efficiency filling mining with self-expanding roof contact of the filling material; The specific steps of the method for controlling the shape of the filling heap include: S31. When the height of the filling heap is less than or equal to 0.5 times the mining height, the dropping speed, spraying volume, spraying pressure, and spraying rotation speed are the rated values, the maximum spraying angle increases in real time following the dropping height, spraying continues during the dropping process and sprays cyclically from the minimum spraying angle to the maximum spraying angle; S32. When the height of the filling heap is greater than 0.5 times the mining height and less than 0.75 times the mining height, the dropping speed is reduced to 0.75 times the rated value, the spraying volume, spraying pressure, and spraying rotation speed are the rated values, the maximum spraying angle increases in real time following the dropping height, spraying continues during the dropping process and sprays cyclically from the minimum spraying angle to the maximum spraying angle; S33. When the height of the filling heap is greater than 0.75 times the mining height, the dropping speed is reduced to 0.5 times the rated value, the spraying volume, spraying pressure, and spraying rotation speed increase to 1.25 - 1.5 times the rated value, the maximum spraying angle increases in real time following the dropping height, spraying continues during the dropping process and sprays cyclically from the minimum spraying angle to the maximum spraying angle until the height of the filling heap is equal to the mining height, that is, when the filling heap touches the roof, the dropping process stops, and the spraying process stops 3 - 5 minutes after the dropping process; 2. The efficient filling mining method based on gangue-cemented highly porous materials as claimed in claim 1, wherein The high-porosity material is selected from bulk coal gangue materials, and its porosity reaches more than 50%.

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