Open pit end slope coal pressure combined mining method

Abstract

The application provides an open-pit end-slope coal pressure mining method, which comprises the following steps: arranging an access roadway at the bottom of an open-pit mine; normally arranging a soil discharge area above the access roadway; prolonging the length of the access roadway along with the advance of the soil discharge area of the open-pit mine; arranging a through roadway in the end-slope of the open-pit mine; connecting the through roadway with the access roadway; making the through roadway pass through the end-slope; arranging a boundary main roadway along the outer edge of the open-pit mine; connecting the boundary main roadway with the through roadway; mining the end-slope coal in the boundary main roadway; and transporting the mined end-slope coal out of the boundary main roadway through the through roadway and the access roadway in sequence. With the normal advance of the open-pit mine, the soil discharge area covers the access roadway, and only the entrance and exit of the access roadway are exposed at the bottom of the open-pit mine. The through roadway connects the access roadway with the boundary main roadway, and the boundary main roadway is arranged at the outer edge of the open-pit mine, so that the end-slope is not disturbed, the strength of the end-slope is not affected, and the influence of mining the end-slope on the normal mining of the open-pit mine is avoided.

Description

Technical Field

[0001] This invention relates to the field of coal mining technology, and more specifically, to a method for combined mining of coal with end-face pressure in open-pit mines. Background Technology

[0002] Currently, open-pit coal mining mainly employs an inverted trapezoidal layered stripping method, resulting in significant coal pressure on the end faces and impacting mine recovery rates. Existing technologies utilize a combined open-pit and shaft mining approach to recover end-face coal, involving the deployment of underground mining systems within the open-pit end faces. However, deploying underground mining systems on the end faces disturbs them, potentially rendering the originally designed stable slope angle unsafe and requiring reduction, leading to substantial coal pressure on the end faces. Furthermore, the underground roadways within the end faces affect their load-bearing capacity, adversely impacting the existing open-pit mine transportation system. Therefore, a combined open-pit and shaft mining approach is needed to address end-face coal pressure, leveraging the advantages of combined open-pit and shaft mining while avoiding interference with the existing open-pit mine production system. Summary of the Invention

[0003] This invention provides a method for joint mining of coal under end-side pressure in open-pit mines, in order to solve the problem of disturbance caused by end-side mining to open-pit mining in the prior art.

[0004] To address the aforementioned problems, this invention provides a method for combined mining of end-side coal in open-pit mines, comprising: arranging an access roadway at the bottom of the open-pit mine, with normal soil dumping above the access roadway, the length of the access roadway extending as the spoil heap of the open-pit mine advances; arranging a through roadway within the end-side of the open-pit mine, the through roadway connecting to the access roadway and passing through the end-side; arranging a boundary roadway along the outer edge of the open-pit mine, connecting the boundary roadway to the through roadway; mining end-side coal in the boundary roadway, the mined end-side coal being transported out from the boundary roadway sequentially through the through roadway and the access roadway.

[0005] Furthermore, an access tunnel is provided at the junction of the end wall and the bottom of the pit, and a connecting opening is provided on the side of the access tunnel near the spoil heap, which is connected to the through tunnel.

[0006] Furthermore, there are multiple connecting tunnels, which are distributed side by side between the boundary main tunnel and the entrance / exit tunnel. When the entrance / exit tunnel and the boundary main tunnel extend the annual advance length of the open-pit mine by 1 / 4 to 1 / 3, a new connecting tunnel is set up.

[0007] Furthermore, when the amount of end coal mined is less than the preset value, a narrow-body car is used to enter the boundary main roadway and transport the mined end coal out; when the amount of end coal mined is greater than or equal to the preset value, a conveyor belt is set up in the boundary main roadway to transport the end coal.

[0008] Furthermore, mining proceeds from the boundary main roadway towards the end wall, with coal pillars reserved during the mining process in the mining area. After the mining area is mined, the coal pillars support the end wall.

[0009] Furthermore, the stripping material generated from coal mining in the next mining area is transported to the previous mining area for backfilling, so as to support the end walls through the stripping material.

[0010] Furthermore, the ratio of the width of the mining area to the width of the coal pillar is 5:1 to 3:1.

[0011] Furthermore, the open-pit mine end-side coal mining method also includes: when the excavation length of the boundary main roadway reaches the advancement length of 1 to 1.5 years, a stage shaft is set up, and the stage shaft is connected to the boundary main roadway.

[0012] Furthermore, the stage shaft is equipped with a hoisting device, from which the end coal mined in the boundary main roadway is transported out; the stage shaft is also used for ventilation, water supply and power supply for the access roadway, boundary main roadway and connecting roadway.

[0013] Furthermore, the positions of the entrance / exit lane, the boundary lane, and the connecting lane are all lower than the bottom of the stage shaft. The end of the entrance / exit lane closest to the spoil heap, the boundary lane, and the connecting lane are all higher than the end of the entrance / exit lane furthest from the spoil heap. Water in the entrance / exit lane, the boundary lane, the connecting lane, and the stage shaft is discharged from the end of the entrance / exit lane furthest from the spoil heap.

[0014] This invention provides a method for combined mining of end-side coal in open-pit mines, comprising: arranging access roadways at the bottom of the open-pit mine, with normal soil dumping above the access roadways, the length of which extends as the spoil heap of the open-pit mine advances; arranging a through roadway within the end-side of the open-pit mine, connecting the through roadway and the access roadway, and passing through the end-side; arranging a boundary roadway along the outer edge of the open-pit mine, connecting the boundary roadway and the through roadway; mining end-side coal in the boundary roadway, with the mined end-side coal being transported out from the boundary roadway sequentially through the through roadway and the access roadway. In this method, access roadways are arranged at the bottom of the open-pit mine. As the open-pit mine advances normally, the spoil heap covers the access roadways, leaving only the entrances and exits exposed at the bottom. The through roadway connects the access roadway and the boundary roadway, allowing personnel to enter the boundary roadway from the access roadway via the through roadway for mining operations. Coal mined in the boundary roadway can be transported out through the through roadway into the access roadway. Setting the boundary main roadway at the outer edge of the open-pit mine will not disturb the end face or affect its strength, thus avoiding the impact of mining the end face on the normal operation of the open-pit mine. Attached Figure Description

[0015] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0016] Figure 1 A flowchart of the open-pit mine end-side coal mining method provided by an embodiment of the present invention is shown;

[0017] Figure 2 It shows Figure 1 A schematic diagram of the structure of an open-pit mine;

[0018] Figure 3 It shows Figure 1 A schematic diagram of the structure of an open-pit mine after a period of mining;

[0019] Figure 4 It shows Figure 1 A schematic diagram of the backfill structure for the stripped material from an open-pit mine.

[0020] The above figures include the following reference numerals:

[0021] 1. Pit bottom; 2. Waste dump; 3. End side; 4. Entrance / exit roadway; 5. Through roadway; 6. Boundary main roadway; 7. Stage shaft; 8. Mining area; 9. Coal pillar. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0023] like Figures 1 to 4 As shown, an embodiment of the present invention provides a method for joint mining of end-side coal in an open-pit mine, comprising: arranging an access roadway 4 at the bottom 1 of the open-pit mine, with normal soil dumping above the access roadway 4, the length of the access roadway 4 extending as the spoil heap 2 of the open-pit mine advances; arranging a through roadway 5 within the end-side 3 of the open-pit mine, the through roadway 5 connecting to the access roadway 4, the through roadway 5 passing through the end-side 3; arranging a boundary roadway 6 along the outer edge of the open-pit mine, connecting the boundary roadway 6 to the through roadway 5; mining end-side coal in the boundary roadway 6, the mined end-side coal being transported out from the boundary roadway 6 sequentially through the through roadway 5 and the access roadway 4.

[0024] In this scheme, an access roadway 4 is arranged at the bottom 1 of the open-pit mine. As the open-pit mine advances normally, the spoil heap 2 covers the access roadway 4, leaving only the entrance and exit of the access roadway 4 exposed at the bottom 1. A connecting roadway 5 connects the access roadway and the boundary main roadway 6, allowing personnel to enter the boundary main roadway 6 from the access roadway 4 via the connecting roadway 5 for mining operations. Coal mined in the boundary main roadway 6 can be transported out through the connecting roadway 5 into the access roadway 4. Positioning the boundary main roadway 6 at the outer edge of the open-pit mine avoids disturbance to the end walls 3, does not affect the strength of the end walls 3, and prevents the mining of the end walls 3 from impacting the normal operation of the open-pit mine.

[0025] like Figure 2 As shown, the entrance / exit lane 4 is set at the junction of the end wall 3 and the bottom of the pit 1. The side of the entrance / exit lane 4 near the spoil heap 2 has a connecting opening, which is connected to the through lane 5.

[0026] With this configuration, the access road 4 is located at the junction of the end wall 3 and the pit bottom 1, and is covered by the spoil heap 2 as it advances. The configuration of the access road 4 will not disturb the end wall 3. The access road 4 is connected to the through road 5, which connects the access road 4 to the boundary main road 6. The through road 5 crosses the end wall 3, so its impact on the end wall 3 is minimal.

[0027] like Figure 3 As shown, there are multiple connecting tunnels 5, which are distributed side by side between the boundary main tunnel 6 and the access tunnel 4. When the access tunnel 4 and the boundary main tunnel 6 extend the annual advance length of the open-pit mine by 1 / 4 to 1 / 3, a new connecting tunnel 5 is set up.

[0028] With this setup, multiple through-runways 5 are arranged side by side between the boundary main runway 6 and the entrance / exit runway 4. When the advance length of the open-pit mine reaches 1 / 4 to 1 / 3 of the annual advance length, a new through-runway 5 is set up, so that the new through-runway 5 is closer to the exit of the entrance / exit runway 4, saving time in transporting the mined coal.

[0029] Furthermore, when the amount of end coal mined is less than the preset value, a narrow-body car is used to enter the boundary main roadway 6 and transport the mined end coal out; when the amount of end coal mined is greater than or equal to the preset value, a conveyor belt is set up in the boundary main roadway 6 to transport the end coal.

[0030] With this setup, when the amount of coal mined from the end face is less than a preset value, a narrow-body vehicle is used to enter the boundary main roadway 6 and transport the mined end face coal out, which is relatively quick and saves resources. When the amount of coal mined from the end face is greater than or equal to the preset value, a conveyor belt is installed in the boundary main roadway 6 to transport the coal, which is more convenient and saves manpower. In a specific embodiment of the present invention, the access roadway 4, the connecting roadway 5, and the boundary main roadway 6 are constructed using precast pipes with a diameter of about 5 meters or by pouring concrete.

[0031] like Figure 4As shown, mining proceeds from the boundary main roadway 6 towards the end wall 3. During the mining process of mining area 8, a coal pillar 9 is reserved. After mining area 8 is mined, the coal pillar 9 supports the end wall 3.

[0032] With this configuration, the side of the boundary main roadway 6 facing the open-pit mine can accommodate personnel and machinery for mining the end wall 3. A coal pillar 9 is reserved between the two mining areas 8 to support the end wall 3 and prevent it from collapsing.

[0033] like Figure 4 As shown, the stripping material generated from coal mining in the next mining area 8 is transported to the previous mining area 8 for backfilling, so as to support the end wall 3 through the stripping material.

[0034] This setup allows the stripping material generated from coal mining in the next mining area 8 to be transported to the previous mining area 8 for backfilling, which can reduce the possibility of end wall 3 collapse. The stripping material is used to support end wall 3, making use of waste and saving resources.

[0035] Furthermore, the ratio of the width of the mining area 8 to the width of the coal pillar 9 is 5:1 to 3:1.

[0036] With this setup, the ratio of the width of the mining area 8 to the width of the coal pillar 9 is 5:1 to 3:1. Within this ratio range, the degree of coal mining can be greater, and the safety of the end wall 3 can be guaranteed to a greater extent, reducing the possibility of collapse.

[0037] like Figure 3 As shown, the open-pit mine end-side pressing coal mining method also includes: when the excavation length of the boundary main roadway 6 reaches the advancement length of 1 to 1.5 years, a stage shaft 7 is set up, and the stage shaft 7 is connected to the boundary main roadway 6.

[0038] With this setup, when the excavation length of the boundary main roadway 6 reaches the advancement length of 1 to 1.5 years, a stage shaft 7 is set up. The stage shaft 7 can serve the boundary main roadway 6, the connecting roadway 5, and the access roadway 4 within the mining area.

[0039] Furthermore, a hoisting device is installed in the stage shaft 7, and the end coal mined in the boundary main roadway 6 is transported out from the stage shaft 7; the stage shaft 7 is also used for ventilation, water supply and power supply for the access roadway 4, the boundary main roadway 6 and the connecting roadway 5.

[0040] This configuration allows mined coal to be transported out from either the access roadway 4 or the stage shaft 7, improving coal transportation efficiency. Furthermore, the stage shaft 7 is also used for ventilation, water supply, and power supply to the access roadway 4, the boundary main roadway 6, and the connecting roadway 5, ensuring the safety of underground personnel and improving work efficiency.

[0041] In a specific embodiment of the present invention, the positions of the entrance / exit lane 4, the boundary lane 6, and the connecting lane 5 are all lower than the bottom of the stage shaft 7. The end of the entrance / exit lane 4 that is closer to the spoil heap 2, the boundary lane 6, and the connecting lane 5 are all higher than the end of the entrance / exit lane 4 that is farther away from the spoil heap 2. The water in the entrance / exit lane 4, the boundary lane 6, the connecting lane 5, and the stage shaft 7 is discharged from the end of the entrance / exit lane 4 that is farther away from the spoil heap 2.

[0042] This arrangement facilitates drainage. Water from the entrance / exit lane 4, boundary lane 6, connecting lane 5, and stage shaft 7 is discharged from the end of the entrance / exit lane 4 away from the spoil heap 2, avoiding water accumulation that could threaten personnel and maintaining environmental hygiene and safety in the entrance / exit lane 4, boundary lane 6, connecting lane 5, and stage shaft 7.

[0043] In one specific embodiment of the present invention, the angle between the line connecting the bottom wall of the stage shaft 7 and the end of the access roadway 4 away from the spoil heap 2 and the horizontal plane is 2° to 5°, preferably 3°, which is more conducive to drainage.

[0044] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0045] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0046] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0047] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0048] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0049] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

Claims

1. A method for combined mining of coal with end-face support in open-pit mines, characterized in that, include: An access road (4) is arranged at the bottom (1) of the open-pit mine. The soil is normally discharged above the access road (4). The length of the access road (4) is extended as the spoil heap (2) of the open-pit mine is advanced. A through roadway (5) is arranged in the end wall (3) of the open-pit mine. The through roadway (5) is connected to the entrance roadway (4). The through roadway (5) passes through the end wall (3). A boundary roadway (6) is arranged along the outer edge of the open-pit mine, connecting the boundary roadway (6) with the through roadway (5); The end-side coal is mined in the boundary main roadway (6), and the mined end-side coal is transported out from the boundary main roadway (6) through the through roadway (5) and the inlet / outlet roadway (4) in sequence; The access lane (4) is set at the junction of the end wall (3) and the bottom of the pit (1). The side of the access lane (4) near the spoil heap (2) has a connecting opening, which is connected to the through lane (5).

2. The open-pit mine end-face coal mining method according to claim 1, characterized in that, There are multiple through-tunnels (5), and multiple through-tunnels (5) are distributed side by side between the boundary main tunnel (6) and the entrance / exit tunnel (4). When the entrance / exit tunnel (4) and the boundary main tunnel (6) extend the annual advance length of the open-pit mine by 1 / 4 to 1 / 3, a new through-tunnel (5) is set up.

3. The open-pit mine end-face coal mining method according to claim 1, characterized in that, When the amount of end coal mined is less than the preset value, a narrow-body car is used to enter the boundary roadway (6) and transport the mined end coal out; when the amount of end coal mined is greater than or equal to the preset value, a conveyor belt is set up in the boundary roadway (6) to transport the end coal.

4. The open-pit mine end-face coal mining method according to claim 1, characterized in that, Mining proceeds from the boundary roadway (6) toward the end wall (3). During the mining process in the mining area (8), a coal pillar (9) is reserved. After the mining area (8) is mined, the coal pillar (9) supports the end wall (3).

5. The open-pit mine end-face coal mining method according to claim 4, characterized in that, The stripping material generated from coal mining in the next mining area (8) is transported to the previous mining area (8) for backfilling to support the end wall (3) with the stripping material.

6. The open-pit mine end-face coal mining method according to claim 4, characterized in that, The ratio of the width of the mining area (8) to the width of the coal pillar (9) is 5:1 to 3:

1.

7. The open-pit mine end-face coal mining method according to claim 1, characterized in that, The open-pit coal mining method with end-face compression also includes: When the excavation length of the boundary main roadway (6) reaches the advancement length of 1 to 1.5 years, a stage shaft (7) is set up, which is connected to the boundary main roadway (6).

8. The open-pit mine end-face coal mining method according to claim 7, characterized in that, The stage shaft (7) is equipped with a hoisting device, and the end coal mined in the boundary main roadway (6) is transported out from the stage shaft (7); the stage shaft (7) is also used for ventilation, water supply and power supply for the entrance roadway (4), the boundary main roadway (6) and the through roadway (5).

9. The open-pit mine end-side coal mining method according to claim 7, characterized in that, The positions of the entrance / exit lane (4), the boundary lane (6), and the through lane (5) are all lower than the bottom of the stage shaft (7). The end of the entrance / exit lane (4) near the spoil heap (2), the boundary lane (6), and the through lane (5) are all higher than the end of the entrance / exit lane (4) away from the spoil heap (2). The water in the entrance / exit lane (4), the boundary lane (6), the through lane (5), and the stage shaft (7) is discharged from the end of the entrance / exit lane (4) away from the spoil heap (2).

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