Gob disposal method and gob disposal system by grouting and filling

Abstract

This invention belongs to the field of mining technology, specifically relating to a method and system for grouting and backfilling gangue disposal. The method includes determining the stability and type of the immediate roof, calculating the immediate roof filling coefficient, determining the basic roof pressure step distance, determining a preset angle between the extension direction of the goaf face and the horizontal plane, determining the grouting hole height and the roof subsidence at the grouting hole location, determining the filling lag distance based on the immediate roof type, grouting hole height, immediate roof filling coefficient, the preset angle between the extension direction of the goaf face and the horizontal plane, and the basic roof pressure step distance, and performing grouting and backfilling based on the filling lag distance. This method can increase the amount of backfilled gangue, and improve the stability and safety of the backfilled gangue.

Description

Technical Field

[0001] This invention belongs to the field of mining technology, specifically relating to a method and system for grouting and backfilling gangue disposal. Background Technology

[0002] With the high-intensity mining of coal in my country, a large amount of coal gangue solid waste is generated during coal mine production. Due to the huge output of coal gangue, it has gradually become the largest industrial solid waste in my country. In order to adapt to the increasingly stringent national environmental protection policies, slurry backfilling, as a new type of coal gangue solid waste disposal method with high efficiency, high capacity and low interference, has been gradually promoted to a certain extent in coal production bases in western my country. Summary of the Invention

[0003] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a method for grouting and backfilling gangue disposal, which can increase the amount of backfilled gangue and improve the stability and safety of the backfilled gangue.

[0004] The method for grouting and backfilling gangue disposal is characterized by comprising:

[0005] Determine the stability of the immediate top and identify its type;

[0006] Calculate the direct top filling coefficient;

[0007] Determine the basic top pressure step distance;

[0008] The extension direction of the working face in the goaf is determined to have a preset angle with the horizontal plane;

[0009] Determine the height of the grouting hole;

[0010] The amount of top plate subsidence at the grouting hole location;

[0011] The filling lag distance is determined based on the type of direct roof, the height of the grouting hole, the filling coefficient, the angle between the extension direction of the working face of the goaf and the horizontal plane, and the basic roof pressure step distance. Grouting is then carried out according to the filling lag distance.

[0012] The grouting and backfilling gangue disposal method of the present invention can increase the backfilling amount and improve the stability and safety of the backfilled gangue.

[0013] In some embodiments, the immediate roof filling coefficient is calculated using the immediate roof thickness and the coal seam mining thickness, and the immediate roof filling coefficient satisfies: n = h i / 1.3hm, where n is the direct top filling coefficient, h i It is the direct top thickness, h m It refers to the thickness of the coal seam during mining.

[0014] In some embodiments, the immediate roof is an unstable immediate roof or a moderately stable immediate roof, and the immediate roof filling coefficient n < 1, and the delayed filling distance of the goaf satisfies:

[0015] When the immediate roof is an unstable or moderately stable immediate roof, and the immediate roof filling coefficient n≥1, the delayed filling distance L of the goaf satisfies: L=le n / 2 ,

[0016] When the direct roof is a stable direct roof, the delayed filling distance L of the goaf satisfies: L=(h-△h) / sinα, where L is the delayed filling distance of the goaf, l is the basic roof pressure step distance, α is the angle between the extension direction of the goaf working face and the horizontal plane, and △h is the amount of roof subsidence at the grouting hole location.

[0017] In some embodiments, a concrete wall is arranged on the side of the goaf along the goaf. When the length of the concrete wall reaches the delayed filling distance, a brick wall is arranged between two adjacent concrete columns. A first grouting hole is arranged at the end of the brick wall near the ground, and the grouting pipe is connected to the first grouting hole.

[0018] When the distance between the working face cut and the goaf meets the goaf lag filling distance, grout is injected into the goaf through the grouting pipe. Observation holes are arranged at the upper end of the brick wall. Grouting is stopped when the grout spreads to the end of the retaining wall support near the goaf.

[0019] In some embodiments, when the length of the goaf-retention tunnel reaches twice the delayed filling distance, a second grouting hole is provided on the brick wall, and the distance between the second grouting hole and the first grouting hole meets the delayed filling distance of the goaf.

[0020] The grouting and backfilling gangue disposal system of this invention is characterized by comprising a gangue retaining support and a grouting pipeline, wherein the gangue retaining support is provided at one end of the return air connecting roadway adjacent to the goaf.

[0021] The grouting pipe is installed in the return air tunnel, with one end of the grouting pipe extending into the goaf.

[0022] In some embodiments, the grouting and backfilling gangue disposal system further includes a transition support base and a pushing cylinder. One end of the transition support base is connected to one end of the pushing cylinder, and the other end of the pushing cylinder is connected to the gangue retaining support. The pushing cylinder extends along the goaf working face in the direction of extension of the goaf working face.

[0023] In some embodiments, the grouting and backfilling gangue disposal system further includes multiple concrete columns and brick walls. Multiple concrete columns are provided at one end of the gangue retaining support away from the goaf. The multiple concrete columns are arranged at intervals in the extension direction of the working face of the goaf. A brick wall is arranged between two connected concrete columns. A first grouting hole is arranged at one end of the brick wall near the ground. One end of the grouting pipe extends into the first grouting hole.

[0024] In some embodiments, the spacing between the multiple concrete columns is A, and 800mm≤A≤1000mm.

[0025] In some embodiments, the grouting and backfilling gangue disposal system further includes a first pump, the outlet of which is connected to the grouting pipeline. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the grouting and backfilling gangue disposal system according to an embodiment of the present invention.

[0027] Figure 2 yes Figure 1 A schematic diagram of the grouting pipeline.

[0028] Figure 3 yes Figure 1 A schematic diagram of the cutting edge of the working face in the goaf.

[0029] Figure label:

[0030] 1. Goaf area, 2. Goaf roadway, 3. Brick wall, 31. First grouting hole, 4. Grouting pipe, 5. Rock retaining support, 6. Concrete column, 7. Goaf working face cut-out. Detailed Implementation

[0031] Embodiments of the present invention are described in detail below, with examples of these embodiments illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the invention.

[0032] The grouting and backfilling method for handling gangue according to an embodiment of the present invention includes: determining the stability of the immediate roof and identifying the immediate roof type; calculating the immediate roof backfilling coefficient; determining the basic roof pressure step distance; determining that the extension direction of the working face of goaf 1 has a preset angle with the horizontal plane; determining the grouting hole height; and determining the roof subsidence at the grouting hole location.

[0033] The filling lag distance is determined based on the type of direct roof, the location of the grouting hole, the amount of roof subsidence, the height of the grouting hole, the filling coefficient, the angle between the extension direction of the working face of the goaf and the horizontal plane, and the basic roof pressure step distance. Grouting is then carried out according to the filling lag distance.

[0034] Specifically, such as Figures 1 to 3As shown, the stability of the immediate roof is first determined, and then it is classified into unstable, moderately stable, or stable immediate roofs. The height of the grouting hole is the distance between the grouting hole and the lower end face of goaf 1. The preset angle between the extension direction of the goaf working face and the horizontal plane is the angle between the working face of goaf 1 along the front-to-back direction and the ground horizontal plane. The roof subsidence at the location of the grouting hole and the basic roof pressure step distance are determined by the mine pressure monitoring system.

[0035] The filling lag distance is determined based on the type of the immediate roof, the height of the grouting hole, the filling coefficient of the immediate roof, and the pressure step distance of the basic roof. The cut-in 7 of the goaf working face moves forward as the working face advances. That is, when the distance between the cut-in 7 of the goaf working face and the rear end face of the goaf 1 meets the filling lag distance, filling is carried out to avoid grout flowing into the working face during grouting. At the same time, when the downward collapse of the goaf 1 is small, grouting is carried out on the goaf 1 to increase the grouting volume of the goaf 1, thereby increasing the consumption of gangue.

[0036] The grouting and backfilling gangue disposal method of this invention determines the backfilling lag distance based on the type of the direct roof, the location of the grouting hole, the roof subsidence, the backfilling coefficient of the direct roof, and the basic roof pressure step distance. Therefore, when the collapse of goaf 1 is small, grouting is performed on goaf 1, which can increase the backfilling amount of gangue and improve the stability and safety of the backfilled gangue.

[0037] In some embodiments, the immediate roof filling coefficient is calculated using the immediate roof thickness and the coal seam mining thickness, and the immediate roof filling coefficient satisfies: n = h i / 1.3h m Where n is the direct top filling coefficient, h i It is the direct top thickness, h m It refers to the thickness of the coal seam during mining.

[0038] Specifically, such as Figures 1 to 3 As shown, the direct top filling coefficient satisfies: n = h i / 1.3h m Where n is the direct top filling coefficient, h i hm is the thickness of the immediate roof in millimeters, and hm is the coal seam mining thickness in millimeters. By calculating the immediate roof filling coefficient, the filling lag distance can be determined by the type of immediate roof and the basic roof pressure step distance. When the collapse of goaf 1 is small, grouting can be carried out on goaf 1 to increase the filling amount of gangue and improve the stability and safety of the filling gangue.

[0039] In some embodiments, the immediate roof is an unstable immediate roof or a moderately stable immediate roof, and the immediate roof filling coefficient n < 1, and the delayed filling distance of goaf 1 satisfies:

[0040] The immediate roof is either an unstable or moderately stable immediate roof, and the immediate roof filling coefficient n≥1. The delayed filling distance L of goaf 1 satisfies: L=le n / 2 ,

[0041] The direct roof is a stable direct roof, and the delayed filling distance L of goaf 1 satisfies: L=(h-△h) / sinα, where L is the delayed filling distance of goaf 1, l is the basic roof pressure step distance, α is the angle between the extension direction of the working face of goaf 1 and the horizontal plane, and △h is the amount of roof subsidence at the grouting hole position in the goaf.

[0042] Specifically, such as Figures 1 to 3 As shown, α is the angle between the extension direction of the working face of goaf 1 and the horizontal plane. By determining the type of the immediate roof and the immediate roof filling coefficient, for example, when the immediate roof is an unstable immediate roof or a moderately stable immediate roof, the pressure step distance of the immediate roof is measured by the mine pressure monitoring system, and the lag filling distance of goaf 1 is determined in conjunction with the immediate roof filling coefficient. Then, filling is carried out when the distance between the working face cut and goaf 1 meets the lag filling distance, so as to avoid the grout flowing into the working face during grouting. At the same time, when the downward collapse of goaf 1 is small, grouting is carried out on goaf 1 to increase the grouting volume of goaf 1, thereby improving the gangue consumption capacity.

[0043] Optionally, when the direct roof is stable, a preset angle is set between the extension direction of the working face of goaf 1 and the horizontal plane, the height of the grouting hole, and the amount of subsidence of the roof of goaf 1. The delayed filling distance of goaf 1 is then determined. Filling is then carried out when the distance between the working face cut and goaf 1 meets the delayed filling distance, so as to avoid the grout flowing into the working face during grouting. At the same time, when the downward collapse of goaf 1 is small, grouting is carried out on goaf 1 to increase the grouting volume of goaf 1, thereby improving the gangue consumption capacity.

[0044] Furthermore, a concrete wall is arranged on the right side of the goaf sill 2 adjacent to the goaf 1. When the length of the concrete wall in the goaf sill 2 reaches the delayed filling distance, a brick wall 3 is arranged between two adjacent concrete columns 6. A first grouting hole 31 is arranged at one end of the brick wall 3 near the ground. The grouting pipe 4 is connected to the first grouting hole 31.

[0045] When the distance between the working face cut 7 and the goaf 1 meets the delayed filling distance of the goaf 1, grout is injected into the goaf 1 through the grouting pipe 4. An observation hole is arranged at the upper end of the brick wall 3. When the grout spreads to the end of the retaining rock support 5 near the goaf 1, the grouting is stopped, thereby improving the amount of grouting and the safety and stability of the grouting in the goaf 1.

[0046] Furthermore, when the length of the goaf 2 reaches twice the delayed filling distance of the goaf 1, a second grouting hole is set on the brick wall 3, and the distance between the second grouting hole and the first grouting hole 31 meets the delayed filling distance of the goaf 1. After the grout injected into the first grouting hole 31 solidifies, coal mining continues at the working face, and the coal mining face continues to advance. Then, when the cut-off between the goaf 1 and the working face meets the delayed filling distance of the goaf 1, grouting is performed on the goaf 1 through the second grouting hole, thereby avoiding excessive collapse of the goaf 1 from affecting the grouting volume.

[0047] Furthermore, the grouting and backfilling method for handling gangue also includes a third grouting hole. When the length of the goaf roadway 2 reaches three times the delayed backfilling distance of the goaf 1, and the distance between the third grouting hole and the second grouting hole meets the delayed backfilling distance of the goaf 1, after the grout injected into the second grouting hole solidifies, coal mining continues at the working face. The coal mining face continues to advance, and when the cut-off between the goaf 1 and the working face meets the delayed backfilling distance of the goaf 1, grouting is performed on the goaf 1 through the third grouting hole, thereby avoiding excessive collapse of the goaf 1 that affects the grouting volume.

[0048] The grouting and backfilling gangue disposal system of this invention includes a gangue retaining support 5 and a grouting pipe 4. The gangue retaining support 5 is provided at one end of the return air connecting roadway near the goaf 1.

[0049] Grouting pipe 4 is installed in the return air tunnel, with one end of grouting pipe 4 extending into the goaf 1.

[0050] Specifically, such as Figures 1 to 3 As shown, the rock-blocking support 5 is located at the right end of the goaf 1 to prevent slurry from entering the goaf-side roadway 2. The rock-blocking support 5 can also increase the slurry carrying capacity of the goaf 1, increase the slurry level injected into the goaf 1, and thus increase the slurry volume of the goaf 1.

[0051] The grouting and backfilling gangue disposal system of this invention improves the stability and safety of grouting by setting up a gangue retaining support 5 and a grouting pipe 4, with the grouting pipe 4 connected to the ground grouting station. By setting the gangue retaining support 5 at the right end of the goaf 1 to prevent grout from entering the goaf roadway 2, the gangue retaining support 5 can also increase the grout carrying capacity of the goaf 1, increase the grout level injected into the goaf 1, and thus increase the grout volume of the goaf 1.

[0052] Furthermore, the grouting and backfilling gangue disposal system also includes a transition support base and a pushing cylinder. One end of the transition support base is connected to one end of the pushing cylinder, and the other end of the pushing cylinder is connected to the gangue retaining support 5. The pushing cylinder extends along the goaf face cutting 7 towards the goaf face. The pushing cylinder moves forward during grouting, thereby driving the transition support base forward, preventing grout from entering the goaf retainer 2 during grouting, and improving the stability and safety of grouting.

[0053] In some embodiments, the grouting and filling gangue disposal system further includes multiple concrete columns 6 and brick walls 3. Multiple concrete columns 6 are provided at one end of the gangue retaining support 5 away from the goaf 1. The multiple concrete columns 6 are arranged at intervals in the extension direction of the working face of the goaf 1. A brick wall 3 is arranged between two connected concrete columns 6. A first grouting hole 31 is arranged at one end of the brick wall 3 near the ground. One end of the grouting pipe 4 extends into the first grouting hole 31.

[0054] Specifically, such as Figures 1 to 3 As shown, multiple concrete columns 6 are arranged on the right side of the goaf chute 2, and the multiple concrete columns 6 are arranged at intervals in the front-to-back direction. A brick wall 3 is arranged between two connected concrete columns 6 to prevent grout from flowing into the goaf chute 2 during grouting. The end of the brick wall 3 near the ground is provided with a first grouting hole 31, that is, the upper end of the brick wall 3 is provided with a first grouting hole 31. The outlet of the grouting pipe 4 is connected to the first grouting hole 31. When the grouting pipe 4 is not grouting, the outlet of the grouting pipe 4 is sealed, for example, by sealing cloth and high-toughness spray material to seal the outlet of the grouting pipe 4 to prevent air leakage in the goaf 1 and improve the stability and safety of the grouting and backfilling gangue disposal system.

[0055] Furthermore, the spacing between the multiple concrete columns 6 is A, and 800mm≤A≤1000mm. For example, the size of A can be 800mm, 900mm, 950mm, or 1000mm, which can be adjusted according to the actual situation on site to improve the stability and safety of the grouting and filling gangue disposal system.

[0056] Optionally, the grouting and backfilling gangue disposal system also includes a first pump, the outlet of which is connected to the grouting pipe 4. By setting up the first pump, the pressure during grouting can be increased, preventing the grout from clogging the outlet of the grouting pipe 4 and improving the stability and safety of grouting.

[0057] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0058] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0059] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0060] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0061] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0062] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for grouting and backfilling gangue disposal, characterized in that, include: Determine the stability of the immediate top and identify its type; The immediate roof filling coefficient is calculated using the immediate roof thickness and the coal seam mining thickness, and the immediate roof filling coefficient satisfies: n=h i / 1.3h m Where n is the direct top filling coefficient, h i It is the direct top thickness, h m It refers to the thickness of the coal seam during mining; Determine the basic top pressure step distance; The extension direction of the working face in the goaf is determined to have a preset angle with the horizontal plane; Determine the height of the grouting hole; The amount of top plate subsidence at the grouting hole location; The filling lag distance is determined by the direct roof type, grouting hole height, filling coefficient, and the pre-set angle and basic roof pressure step distance between the extension direction of the goaf working face and the horizontal plane. Grouting and filling are carried out according to the filling lag distance. When the immediate roof is an unstable or moderately stable immediate roof, and the immediate roof filling coefficient n < 1, the delayed filling distance of the goaf satisfies the following: , When the immediate roof is an unstable or moderately stable immediate roof, and the immediate roof filling coefficient n≥1, the delayed filling distance L of the goaf satisfies: , The direct roof is a stable direct roof, and the delayed filling distance L of the goaf satisfies: L=(h-△h) / sinα, where L is the delayed filling distance of the goaf, l is the basic roof pressure step distance, α is the angle between the extension direction of the goaf working face and the horizontal plane, h is the height of the grouting hole, and △h is the amount of roof subsidence at the grouting hole location.

2. The method for grouting and backfilling gangue disposal according to claim 1, characterized in that, A concrete wall is installed on the side of the goaf adjacent to the goaf in the goaf-keeping roadway. When the length of the concrete wall reaches the delayed filling distance, a brick wall is installed between two adjacent concrete columns. The first grouting hole is installed at the end of the brick wall near the ground, and the grouting pipe is connected to the first grouting hole. When the distance between the working face cut and the goaf meets the goaf lag filling distance, grout is injected into the goaf through the grouting pipe. Observation holes are arranged at the upper end of the brick wall. Grouting is stopped when the grout spreads to the end of the retaining wall support near the goaf.

3. The method for grouting and backfilling gangue disposal according to claim 1, characterized in that, When the length of the goaf-side roadway reaches twice the delayed filling distance of the goaf, a second grouting hole is set on the brick wall, and the distance between the second grouting hole and the first grouting hole meets the delayed filling distance of the goaf.

4. A grouting and backfilling system for handling gangue, characterized in that, The system includes a rock-blocking support and grouting pipes. The rock-blocking support is installed at one end of the return air connecting roadway near the goaf. The grouting pipe is installed in the return air tunnel, with one end of the grouting pipe extending into the goaf.

5. The grouting and backfilling gangue disposal system according to claim 4, characterized in that, It also includes a transition support base and a pushing cylinder. One end of the transition support base is connected to one end of the pushing cylinder, and the other end of the pushing cylinder is connected to the rock-blocking support. The pushing cylinder extends along the direction of the goaf working face extension.

6. The grouting and backfilling gangue disposal system according to claim 5, characterized in that, It also includes multiple concrete columns and brick walls. Multiple concrete columns are provided at one end of the retaining wall away from the goaf. The multiple concrete columns are arranged at intervals in the extension direction of the working face of the goaf. A brick wall is arranged between two connected concrete columns. A first grouting hole is arranged at one end of the brick wall near the ground. One end of the grouting pipe extends into the first grouting hole.

7. The grouting and backfilling gangue disposal system according to claim 6, characterized in that, The spacing between multiple concrete columns is A, and 800mm≤A≤1000mm.

8. The grouting and backfilling gangue disposal system according to claim 7, characterized in that, It also includes a first pump, the outlet of which is connected to the grouting pipe.

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