A step-by-step semi-continuous mining method for thick coal seam open-pit mines

Abstract

The present invention provides a step-by-step semi-continuous mining method for open-pit mines in extremely thick coal seams. This method fully utilizes the characteristics of strong production capacity of semi-fixed crushers and low transportation cost of belt conveyors, and utilizes two semi-fixed crushers and two belt conveyors to form two sets of semi-continuous process systems. Through the step-by-step relocation method, the open-pit raw coal mining is completed. Since the working face distance of extremely thick coal seams is long and the advancement is small, time preparation can be provided for the implementation of the scheme of the present invention; the present invention combines the dual advantages of the intermittent process of the working face and the continuous transportation process of the end ribs, and has the characteristics of flexible production layout, low transportation cost, and stable production; the two crushers are arranged in a step-by-step manner, and the two do not affect each other, ensuring that the mine does not stop production; the semi-fixed crusher has a large production capacity and a relatively simple relocation process, which can ensure that the other one is relocated before the service period of one expires; the present invention does not affect the transportation system of the original mine, ensures the stability of mine production, and is convenient for existing staff to implement.

Description

Technical Field

[0001] The present invention relates to an open-pit mining method, in particular to a step-by-step semi-continuous mining method for an open-pit mine with extremely thick coal seams. Background Art

[0002] In Xinjiang, Inner Mongolia, and other areas of my country, there are a large number of open-pit coal mines with thick coal seams (generally greater than 30m) and simple cover conditions. These mines have high production capacity, long working faces, and short annual advances. During the mining process, due to the long working face arrangement, the use of truck transportation requires long vehicle transportation distances and high costs. In addition, due to the large transportation volume, the road traffic density on the working face is high, posing a safety hazard. Although the use of a self-propelled crusher with a low transportation cost combined with a belt conveyor can avoid the above problems, the self-propelled crusher has a small production capacity, low production stability, and long maintenance time, which seriously affects the production capacity of the open-pit mine. Therefore, it is urgent to propose a mining method that can reduce transportation costs, reduce interference with the normal production of the open-pit mine, improve production stability, and ensure the production capacity of the mine. Summary of the Invention

[0003] In response to the problems existing in the above-mentioned prior art, the present invention provides a step-by-step semi-continuous mining method for thick coal seam open-pit mines, which reduces transportation costs, reduces interference with normal production in open-pit mines, improves production stability, and ensures mine production capacity.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a step-by-step semi-continuous mining method for an open-pit mine of extremely thick coal seams, wherein a segmentation boundary is drawn to divide the open-pit mine working face into a mining section and a preparation section; an end-wall crusher is arranged on the side of the mining section close to the end wall, and the crusher unloading point is one coal mining step higher than the end-wall crusher; an end-wall conveyor is arranged on the coal mining step where the end-wall crusher is located, and the end-wall conveyor connects the end-wall crusher with the surface coal storage bin; the pressure coal under the end-wall crusher is reserved according to the maximum stable wall slope angle and is not mined temporarily; the coal in the mining section is mined in a stepped manner, first mining the coal seam close to the segmentation boundary side, and gradually extending mining to the end-wall side, and stopping mining when the working face advances to the annual designed advancement distance of the open-pit mine, and setting a segmentation crusher close to the segmentation boundary position on the coal mining step where the end-wall crusher is located, and at the same time setting a working face conveyor on the coal mining step where it is located, and following the working face until it extends to the end-wall position; After all the coal seams in the mining section are mined, the end wall crusher is removed and the crusher pressure coal underneath it is mined, and the end wall conveyor is extended until it is connected to the working face conveyor; the segmented crusher is started, and the mining section and the preparation section are interchanged, the mining section becomes the new preparation section, and the preparation section becomes the new mining section; when the coal in the new mining section is mined, the pressure coal under the segmented crusher is reserved according to the maximum stable wall slope angle and is not mined temporarily; during the mining process of the new mining section, a preparation groove is pre-excavated near the end wall in the new preparation section, and the end wall crusher is installed in it after the preparation groove is excavated and formed; when the working face of the new mining section advances to the annual designed advancement distance of the open-pit mine, mining is stopped, the segmented crusher is shut down and dismantled, the other end wall crusher that has been set up is started, the working face conveyor is removed, the new mining section and the new preparation section are interchanged again, and mining of the coal in the new mining section begins again; and so on, alternating steps are taken to complete the semi-continuous mining of the extremely thick coal seam.

[0005] Furthermore, when there are two coal mining steps, the end crusher is set on the coal seam bottom plate, and the crusher unloading point is located on the first coal mining step platform above the coal seam bottom plate.

[0006] Furthermore, when there are three to four coal mining steps, the end crusher is set on the first coal mining step platform, and the crusher unloading point is set on the second coal mining step platform.

[0007] Furthermore, when the coal mining steps are greater than four, the end wall crusher is set on the second coal mining step platform, and the highest shall not exceed the third coal mining step platform. The crusher unloading point is set on a step platform above the end wall crusher.

[0008] Furthermore, when the number of coal mining steps is not less than four, the crusher unloading point is set to two levels, the lower unloading point is one coal mining step higher than the end wall crusher, and the upper unloading point is two coal mining steps higher than the end wall crusher.

[0009] Compared with the existing technology, the present invention has the following advantages: since the working face distance of the extremely thick coal seam is long and the advancement is small, time preparation can be provided for the implementation of the scheme of the present invention; the present invention combines the dual advantages of the intermittent process of the working face and the continuous transportation process of the end wall, and has the characteristics of flexible production layout, low transportation cost and stable production; the two crushers are arranged in a step-by-step manner, and the two do not affect each other, ensuring that the mine does not stop production; the semi-fixed crusher has a large production capacity and a relatively simple relocation process, which can ensure that the other one is relocated in place before the service period of one expires; the present invention does not affect the original mine's transportation system, and can be switched at any time according to actual conditions, ensuring the stability of mine production and facilitating implementation by existing staff. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the working surface of the present invention in sections;

[0011] Figure 2 Prepare schematic diagram for the present invention;

[0012] Figure 3 This is a schematic diagram of the present invention's step mining and new step preparation;

[0013] Figure 4 This is a schematic diagram of the new step mining of the present invention;

[0014] Figure 5 This is a schematic diagram of the arrangement of the end crusher and the crusher unloading point when the coal mining step is not less than four in the present invention;

[0015] In the figure: 1. Working face, 2. Segment boundary, 3. Mining section, 3-1. New mining section, 4. Preparation section, 4-1. New preparation section, 5. End wall, 6. End wall crusher, 6-1. Lower unloading point, 6-2. Upper unloading point, 7. Crusher unloading point, 7-1. Coal seam floor, 7-2. First coal mining step, 7-3. Second coal mining step, 8. Coal mining step, 9. End wall conveyor, 10. Coal pressing, 11. Gentle slope coal chute, 12. Segment crusher, 13. Working face conveyor, 14. Preparation chute. DETAILED DESCRIPTION

[0016] The present invention will be further described below with reference to the accompanying drawings.

[0017] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0018] like Figures 1 to 5As shown, the present invention provides a technical solution: fully utilizing the characteristics of strong production capacity of semi-stationary crushers and low transportation cost of belt conveyors, two sets of semi-continuous process systems are composed of two semi-stationary crushers and two belt conveyors, and open-pit raw coal mining is completed through step-by-step transfer.

[0019] Working face segmentation: Figure 1 and Figure 2 As shown, the open-pit mine working face 1 is divided into two sections by demarcating a segmentation boundary 2 according to the principle of similar coal coverage and reserves. The section close to the surface industrial square of the open-pit mine is the mining section 3, and the other section is the preparation section 4.

[0020] Installation of semi-stationary crusher: Install end wall crusher 6 on the side of mining section 3 close to end wall 5. The installation height of end wall crusher 6 is determined according to the principle of lowest cost of transporting coal from mining section 3 to crusher unloading point 7, where crusher unloading point 7 is one coal mining step 8 higher than end wall crusher 6; Figure 5 As shown, when there are two coal mining steps 8, the end wall crusher 6 is set on the coal seam bottom plate 7-1, and the crusher unloading point 7 is located on the first coal mining step 7-2 platform above the coal seam bottom plate 7-1; when there are three to four coal mining steps 8, in order to reduce the up- or down-transportation distance of coal on the working face 1, the end wall crusher 6 is set on the first coal mining step 7-2 platform, and the crusher unloading point 7 is set on the second coal mining step 7-3 platform; when there are more than four coal mining steps 8, in order to ensure the stability of the base of the semi-fixed end wall crusher 6 and reduce the pressure of the end wall crusher 6 on the coal, the end wall crusher 6 is set on the second coal mining step 7-3 platform, and the highest shall not exceed the third coal mining step platform, and the crusher unloading point 7 is set on a step platform above the end wall crusher 6.

[0021] Arrange conveyor: arrange end wall conveyor 9 on the coal mining step 8 where end wall crusher 6 is located, one end of end wall conveyor 9 is connected to end wall crusher 6, and the other end extends to the surface coal storage bin through the end wall of the open-pit mine; the excavated coal is transported to the crusher unloading point 7 by truck for unloading and crushing, and the pressure coal 10 under the end wall crusher 6 is reserved according to the maximum stable wall slope angle and is not mined temporarily; when the coal mining steps 8 are not less than four, the crusher unloading point 7 is set as two layers, the lower unloading point 6-1 is one coal mining step 8 higher than the end wall crusher 6, and the upper unloading point 6-2 is two coal mining steps 8 higher than the end wall crusher 6. The coal unloaded from the lower unloading point 6-1 directly enters the crushing port of the end wall crusher 6 for crushing, and the coal unloaded from the upper unloading point 6-2 slides through the gentle slope coal chute 11 to the lower unloading point 6-1 and flows into the crushing port.

[0022] Preparation for the first step: The coal in mining section 3 adopts a step mining method, that is, the coal seam close to the segment boundary 2 is mined first, and then the mining is gradually extended to the end wall 5 side. Mining is stopped when the working face 1 advances to the annual design advancement distance of the open-pit mine. On the coal mining step 8 where the end wall crusher 6 is located, a segment crusher 12 is set near the segment boundary 2, and at the same time, a working face conveyor 13 is set on the coal mining step 8, and follows the working face until it extends to the end wall 5 position.

[0023] Step by step: After the mining section 3 coal seam is fully mined, the end wall crusher 6 is removed and the crusher pressure coal 10 below it is mined. Figure 3 and Figure 4 As shown, the end conveyor 9 is extended until it is connected to the working face conveyor 13; the segmented crusher 12 is started, and the mining section 3 and the preparation section 4 are interchanged, the mining section 3 becomes the new preparation section 4-1, and the preparation section 4 becomes the new mining section 3-1.

[0024] Step by step mining: mine the coal in the new mining section 3-1, and the mined coal will be transported to the crusher unloading point 7 by truck for unloading and crushing. The compressed coal 10 under the segmented crusher 12 will be reserved according to the maximum stable slope angle and will not be mined for the time being.

[0025] Preparation for a new step: During the mining process of the new mining section 3-1, a preparation groove 14 is pre-excavated in the new preparation section 4-1 near the end wall 5. The coal excavated from the preparation groove 14 is transported to the crusher by truck. After the preparation groove 14 is excavated and formed, an end wall crusher 6 is set in it.

[0026] New step in mining: When the working face 1 of the new mining section 3-1 advances to the annual designed advancement distance of the open-pit mine, mining is stopped, the segmented crusher 12 is shut down and dismantled, the other end crusher 6 that has been set up is started, the working face conveyor 13 is dismantled, the new mining section 3-1 and the new preparation section 4-1 are interchanged again, and mining of the coal in the new mining section begins again.

[0027] By analogy, alternating steps are used to complete the semi-continuous mining of extremely thick coal seams; when the semi-continuous process is shut down due to the implementation of the step plan or maintenance of the semi-continuous process, and the coal from the working face cannot be transported, intermittent transportation can be achieved through the end-wall transportation roads and the working face transportation roads to avoid mine shutdown.

[0028] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0029] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any minor modifications, equivalent replacements, and improvements made to the above embodiments based on the technical essence of the present invention shall be included in the scope of protection of the technical solution of the present invention.

Claims

1. A step-by-step semi-continuous mining method for thick coal seam open-pit mines, characterized by: Delineating a segmentation boundary (2) to divide the open pit working face (1) into a mining segment (3) and a preparation segment (4); An end wall crusher (6) is provided on one side of the mining section (3) close to the end wall (5), and a crusher unloading point (7) is higher than the end wall crusher (6) by one coal mining step (8); An end-wall conveyor (9) is arranged on the coal mining step (8) where the end-wall crusher (6) is located. The end-wall conveyor (9) connects the end-wall crusher (6) with the surface coal storage bin; the pressure coal (10) under the end-wall crusher (6) is reserved according to the maximum stable slope angle and is not mined temporarily; The coal in the mining section (3) is mined in a step-by-step manner, first mining the coal seam near the segment boundary (2) side, and gradually extending the mining to the side of the end wall (5). When the working face (1) advances to the position of the open-pit mine's annual designed advancement distance, the mining is stopped. On the mining step (8) where the end wall crusher (6) is located, a segment crusher (12) is set near the segment boundary (2), and at the same time, a working face conveyor (13) is set on the mining step (8) where it is located, and follows the working face until it extends to the end wall (5); After the mining section (3) coal seam is completely mined, the end wall crusher (6) is removed and the crusher press coal (10) below it is mined, and the end wall conveyor (9) is extended until it is connected to the working face conveyor (13); the segmented crusher (12) is started, and the mining section (3) and the preparation section (4) are interchanged, and the mining section (3) becomes the new preparation section (4-1), and the preparation section (4) becomes the new mining section (3-1); When mining the coal in the new mining section (3-1), the compressed coal (10) under the segmented crusher (12) is reserved according to the maximum stable slope angle and is not mined temporarily; During the mining process of the new mining section (3-1), a preparation groove (14) is pre-excavated near the end wall (5) in the new preparation section (4-1), and an end wall crusher (6) is set in the preparation groove (14) after the preparation groove (14) is excavated and formed; When the working face (1) of the new mining section (3-1) advances to the position of the annual designed advancement distance of the open pit mine, mining is stopped, the segmented crusher (12) is shut down and removed, the other end crusher (6) that has been set up is started, the working face conveyor (13) is removed, the new mining section (3-1) and the new preparation section (4-1) are exchanged again, and mining of the coal in the new mining section begins again; And so on, alternating steps are taken to complete the semi-continuous mining of extremely thick coal seams.

2. The step-by-step semi-continuous mining method for thick coal seam open-pit mines according to claim 1, characterized in that: When there are two coal mining steps (8), the end crusher (6) is arranged on the coal seam floor (7-1), and the crusher unloading point (7) is located on the platform of the first coal mining step (7-2) above the coal seam floor (7-1).

3. The step-by-step semi-continuous mining method for thick coal seam open-pit mines according to claim 1, characterized in that: When there are three to four coal mining steps (8), the end crusher (6) is arranged on the platform of the first coal mining step (7-2), and the crusher unloading point (7) is arranged on the platform of the second coal mining step (7-3).

4. The step-by-step semi-continuous mining method for thick coal seam open-pit mines according to claim 1, characterized in that: When the number of the coal mining steps (8) is greater than four, the end wall crusher (6) is set on the second coal mining step (7-3) platform, and the highest point shall not exceed the third coal mining step platform. The crusher unloading point (7) is set on a step platform above the end wall crusher (6).

5. The step-by-step semi-continuous mining method for thick coal seam open-pit mines according to claim 1, characterized in that: When the number of the coal mining steps (8) is not less than four, the crusher unloading point (7) is set to be upper and lower layers, the lower unloading point (6-1) is one coal mining step (8) higher than the end wall crusher (6), and the upper unloading point (6-2) is two coal mining steps (8) higher than the end wall crusher (6).

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