A filling mining method for high steep slope bottom large angle thick coal seam

Abstract

The present invention discloses a method for filling and mining thick coal seams at a large dip angle at the bottom of a high and steep slope. A continuous coal mining machine is arranged at the bottom of a pit at the foot of a high and steep slope of an open-pit mine. The continuous coal mining machine includes a main system, a cutting part, a propulsion arm system and a coal transporting part. The main system controls the cutting part to recover coal seam resources at a maximum mining angle of 12° (coal seam dip angle α>12°). The coal is transported to the coal transporting part by the propulsion arm system and then transported to a storage bin. The main system performs a bottom plate lowering arrangement process of the underlying rock strata of different degrees in the bottom plate area at the bottom of the pit, and then mines coal in different horizontal strips of the coal seam. A filling station is arranged on a flat plate at the top of the slope, and its filling materials are transported to the mining place through a filling pipeline to form a filling strip. The present invention can realize the large-angle filling and mining of thick coal seams by the continuous coal mining machine through the rock and soil in the bottom plate area, ensure the stability of the high and steep slope, and improve the mining and recovery efficiency of the thick coal seam, which has important practical significance.

Description

Technical Field

[0001] The invention belongs to the technical field of open-pit coal mining, and in particular relates to a filling mining method for a thick coal seam with a large dip angle at the bottom of a high and steep slope. Background Art

[0002] The sidewall mining technology and the effective slope theory have been widely used in open-pit coal mines, but the sidewalls of open-pit mines still occupy a large amount of coal resources. These coal resources have been stored under the slopes for a long time. If mining is abandoned, a large amount of coal resources will be wasted, which is not conducive to the sustainable development of mines and will cause the country to suffer significant resource losses. At present, the commonly used methods for recovering coal resources from the sidewalls of open-pit coal mines are steep sidewall mining, effective slope, sidewall tunnel filling mining, and continuous coal mining. Steep sidewall mining technology and effective slope theory further improve the slope mining angle and complete the coal mining at the extreme mining angle of the sidewall slope within a certain period of time, but it cannot solve the situation of coal mining under the sidewall. The sidewall tunnel filling mining technology overcomes the limitations of steep sidewall mining technology, but according to relevant national laws and regulations and mining costs, the sidewall tunnel filling mining technology is restricted. At present, continuous coal mining technology is used at the sidewalls at home and abroad. Due to the limitations of continuous coal mining machines, only medium and thick coal seams with an inclination of +5° to -12° can be mined, and a large number of coal pillars are retained, resulting in certain coal resource losses. Therefore, it is necessary to use certain technologies and methods to solve the problem of continuous miner mining thick coal seams with large inclinations. Summary of the invention

[0003] In view of the shortcomings of the prior art, the present invention provides a filling mining method for the thick coal seam with a large inclination angle at the bottom of a steep slope, which can not only realize the recovery of the thick coal seam resources with a large inclination angle, but also reduce surface subsidence, ensuring the safety of the mining site and the stability of the slope.

[0004] The present invention is achieved through the following technical solutions:

[0005] A filling mining method for a thick coal seam with a large dip angle at the bottom of a high and steep slope comprises the following steps:

[0006] Step 1) When the inclination angle α of the coal seam is greater than 12°, a continuous coal mining machine is arranged at the bottom of the pit at the foot of the steep slope of the open-pit mine, wherein the continuous coal mining machine comprises a main system, a cutting part, a propulsion arm system and a coal transport part, wherein the main system and the coal transport part are arranged in the broken bottom plate area at the bottom of the pit; the main system controls the cutting part to open up a mining tunnel at a maximum mining angle of 12° to recover resources from the coal seam, and the coal in the mining tunnel is transported to the belt conveyor of the coal transport part through the propulsion arm system and then transported to a storage bin;

[0007] Step 2) a filling station is arranged at the top flat plate of the high and steep slope of the open-pit mine, and a filling pipeline is arranged from the filling station downward along the slope surface, the filling pipeline extends to the mining place, and the filling material of the filling station is transported to the mining place through the filling pipeline;

[0008] Step 3) The cutting part of the continuous miner mines the coal seam to form a series of mining tunnels, the size of each mining tunnel is determined according to the mechanical strength of the coal, the height of the overlying rock layer and the mining height of the cutting part of the continuous miner, and the mining tunnels are filled with filling materials to form a series of filling strips;

[0009] Step 4) the main system performs floor breaking lowering arrangement processing of different degrees of underlying rock formations in the floor breaking area at the bottom of the pit, thereby mining coal in different horizontal strips of the coal seam;

[0010] Step 5) Once the entire coal seam has been mined, a series of fill strips will form a "masonry wall" structure.

[0011] Preferably, in step 3), when the continuous coal mining machine mines the coal seam on the same horizontal strip, according to the width W of the first mining tunnel A c Open up more than one mining tunnel of the same width, and after mining the first mining tunnel A, skip the width W of the second mining tunnel B c Directly open up the third mining shaft C and continue mining. Carry out the first round of coal resource skip mining in the order of this interval mining until only one mining shaft width W is left on this horizontal strip of coal seam. c When the coal is mined, it returns to the second mining shaft B that was skipped for the first time, develops mining shaft B and carries out the second round of skip mining of coal resources in the order of interval mining. The coal seam on each horizontal strip needs to undergo two rounds of skip mining of coal resources. The filling sequence lags behind the skip mining sequence by one mining shaft, that is, when mining shaft A is mined and mining shaft C is ready to be mined, the filling work of mining shaft A is carried out.

[0012] Preferably, the filling material includes a first filling body and a second filling body, wherein the first filling body and the second filling body are spaced apart from each other for filling operations, that is, if mining shaft A and mining shaft C are filled with the first filling body, then mining shaft B is filled with the second filling body, and vice versa; when all the mining shafts on the same horizontal strip are mined, the filling strips formed by the first filling body and the second filling body spaced apart from each other constitute the filling strip of this horizontal strip, and on this basis, coal resources are mined downward in the next horizontal strip.

[0013] Preferably, in the vertical direction, when the filling strip of the previous horizontal strip is filled, when the coal resources of the next horizontal strip are mined, the mining holes at the two side edges of the next horizontal strip need to be offset from the filling strips at the two side edges of the previous horizontal strip by half the width of the mining hole 1 / 2W. cAt the same time, the width of the permanent coal pillar on the previous horizontal strip and the permanent coal pillar on the next horizontal strip also differs by half the width of the mining tunnel, 1 / 2W. c .

[0014] Preferably, in step 4), the bottom plate breaking area has a minimum bottom plate breaking area width W according to the minimum operating size of the main system. min , the depth H of the bottom plate breaking area min It needs to be determined based on the stripping volume of the broken floor area, the length of coal / rock in the mining tunnel and the filling cost.

[0015] The beneficial effects of the present invention are as follows:

[0016] Compared with the prior art, the present invention can realize the large-angle filling and mining of thick coal seams by continuous coal mining machines through the rock and soil in the bottom plate area of ​​the open-pit mine, ensure the stability of high and steep slopes, improve the mining and recovery efficiency of thick coal seams, and save a lot of stripping costs and spoil field accommodation space. The present invention is suitable for filling and mining of thick coal seams with large inclination angles at the bottom of high and steep slopes, which can improve the recovery rate of coal resources in enterprises, realize green, efficient and safe production of mines, and has important practical significance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural cross-sectional view of the high and steep slope mining technology of the present invention;

[0018] Figure 2 A three-dimensional structural schematic diagram of the high and steep slope mining technology of the present invention;

[0019] Figure 3 This is a schematic diagram of the left and right sequence of thick coal seam backfill mining;

[0020] Figure 4 for Figure 2 Schematic diagram of the upper and lower sequence of backfill mining of thick coal seams at the middle MM;

[0021] In the figure: 1. Slope; 2. Overlying rock strata; 3. Coal seam (inclination angle α); 4. Flat plate on top of slope; 5. Underlying rock strata; 6. Pit bottom; 7. Broken bottom plate area; 8. Filling strip; 9. Cutting section; 10. Propelling arm system; 11. Main system; 12. Coal transport section; 13. Storage bin; 14. Filling station; 15. Filling pipeline; 16. Filling material; 17. First filling body; 18. Second filling body; 19. Mining shafts (A, B, C, D, E, F, G, H); 20. Permanent coal pillar. DETAILED DESCRIPTION

[0022] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] Example 1

[0024] A method for backfilling and mining a thick coal seam at a high and steep slope, the specific steps are as follows:

[0025] (1) Figure 1 As shown, when the inclination angle α of the coal seam 3 is greater than 12°, a continuous coal mining machine is arranged at the bottom of the pit 6 at the foot of the steep slope 1 of the open-pit mine, and the continuous coal mining machine includes a main system 11, a cutting part 9, a thrust arm system 10 and a coal transport part 12, wherein the main system 11 and the coal transport part 12 are arranged in the broken bottom plate area 7 of the pit bottom 6; the main system 11 controls the cutting part 9 to open up a mining cave 19 at a maximum mining angle of 12° to recover resources of the coal seam 3, and the coal in the mining cave 19 is transported to the belt conveyor of the coal transport part 12 by the thrust arm system 10, and then transported to the storage bin 13.

[0026] (2) Figure 1 As shown, a filling station 14 is arranged at the flat plate 4 on the top of the steep slope 1 of the open-pit mine, and a filling pipe 15 is arranged from the filling station 14 downward along the slope surface of the slope 1. The filling pipe 15 extends to the mining shaft 19, and the filling material 16 of the filling station 14 is transported to the mining shaft 19 through the filling pipe 15.

[0027] (3) Figure 1 and Figure 2 As shown, the cutting part 9 of the continuous coal mining machine mines the coal seam 3 to form a series of mining chambers 19. The size of each mining chamber 19 is determined according to the mechanical strength of the coal, the height of the overlying rock layer 2 and the mining height of the cutting part 9. The mining chambers 19 are filled with filling materials 16 to form a series of filling strips 8.

[0028] like Figure 3 As shown, when the continuous coal mining machine mines the coal seam 3 on the same horizontal strip, according to the width W of the first mining tunnel A c Develop several mining shafts BH of the same width. After mining the first mining shaft A, skip the width W of the second mining shaft B. c Directly open up the third mining shaft C and continue mining. Carry out the first round of coal resource skipping mining (A→C→E→G) in this interval mining order until only one mining shaft H width W is left on the coal seam 3 on this horizontal strip. c , return to the second mining shaft B that was skipped for the first time, open up mining shaft B and carry out the second round of coal resource skipping mining (B→D→F→H) in the order of interval mining. The coal seam 3 on each horizontal strip needs to undergo two rounds of coal resource skipping mining; the filling sequence lags behind the skipping mining sequence by one mining shaft, that is, when mining shaft A is completed and mining shaft C is ready to be mined, the filling work of mining shaft A is carried out.

[0029] like Figure 2 and Figure 3As shown, the filling material 16 includes a first filling body 17 and a second filling body 18, wherein the first filling body 17 and the second filling body 18 are filled at intervals from each other, that is, if the first filling body 17 is used for filling in the mining shaft A and the mining shaft C, the second filling body 18 is used for filling in the mining shaft B, and vice versa. When the mining shaft G is completed and the mechanical properties of the first filling body 17 filled in the order of A→C→E→G reach a certain strength, the mining shaft B can be prepared for mining. Similarly, when all the mining shafts 19 on the same horizontal strip are mined, the filling strips formed by the second filling body 18 filled in the order of B→D→F→H and the first filling body 17 filled in the order of A→C→E→G are spaced from each other to form a filling strip 8 of this horizontal strip, and on this basis, the coal resources of the next horizontal strip are mined downward.

[0030] The filling material 16 is a mixture of stripping material and cement after mining. The first filling body 17 and the second filling body 18 are made of the same material. In this embodiment, the filling material 16 is divided into two groups of filling bodies to facilitate the distinction of the order of skip mining and filling.

[0031] like Figure 3 and Figure 4 As shown, in the vertical direction, when the filling strip 8 of the previous horizontal strip is filled, when the coal resources of the next horizontal strip are mined, the mining holes 19 (A and H) at the two side edges of the next horizontal strip need to be offset from the filling strips at the two side edges of the previous horizontal strip by half the width of the mining hole 19 1 / 2W c At the same time, the width of the permanent coal pillar 20 on the previous horizontal strip and the permanent coal pillar 20 on the next horizontal strip also differs by half the width of the mining tunnel 19, 1 / 2W. c This can prevent the filling strips on the upper horizontal strip from collapsing, thereby ensuring the stability of the entire filling strip 8.

[0032] (4) Figure 1 As shown, the main system 11 performs floor breaking and descending arrangement processing of the underlying rock layer 5 to different degrees in the floor breaking area 7 of the pit bottom 6, thereby mining coal in different horizontal strips of the coal seam 3.

[0033] like Figure 2 As shown, the bottom plate breaking area 7 at the pit bottom 6 has a minimum bottom plate breaking area width W according to the minimum operating size of the main system 11. min , the depth H of the bottom plate breaking area 7 min It needs to be determined based on reasonable economic costs such as the stripping volume of the broken floor area 7, the length of coal / rock in the mining tunnel 19 and the filling cost.

[0034] (5) Figure 2 and Figure 4As shown, after the entire coal seam 3 is mined, a series of filling strips 8 will form a "masonry wall" structure.

[0035] The above is only a preferred embodiment of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. The embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the attached claims rather than the above embodiments. Therefore, it is intended to include all changes that fall within the meaning and scope of the equivalent elements of the claims in the present invention. Any minor modifications, equivalent substitutions and improvements made to the above embodiments based on the technical essence of the present invention should be included in the protection scope of the technical solution of the present invention.

Claims

1. A method for backfilling and mining a thick coal seam at a high and steep slope, characterized in that: The following steps are involved: Step 1) When the inclination angle α of the coal seam is greater than 12°, a continuous coal miner is arranged at the bottom of the pit at the foot of the steep slope of the open-pit mine, wherein the continuous coal miner comprises a main system, a cutting part, a propulsion arm system and a coal transport part, wherein the main system and the coal transport part are arranged in the broken bottom plate area at the bottom of the pit; the main system controls the cutting part to open up a mining tunnel at a maximum mining angle of 12° to recover resources from the coal seam, and the coal in the mining tunnel is transported to the belt conveyor of the coal transport part through the propulsion arm system and then transported to the storage bin; Step 2) a filling station is arranged at the top flat plate of the high and steep slope of the open-pit mine, and a filling pipeline is arranged from the filling station downward along the slope surface, the filling pipeline extends to the mining place, and the filling material of the filling station is transported to the mining place through the filling pipeline; Step 3) The cutting part of the continuous miner mines the coal seam to form a series of mining tunnels. The size of each mining tunnel is determined according to the mechanical strength of the coal, the height of the overlying rock layer and the mining height of the cutting part of the continuous miner. The mining tunnels are filled with filling materials to form a series of filling strips. When a continuous coal mining machine mines coal seams on the same horizontal strip, according to the width W of the first mining tunnel A c Open up more than one mining tunnel of the same width, and after mining the first mining tunnel A, skip the width W of the second mining tunnel B c Directly open up the third mining shaft C and continue mining. Carry out the first round of coal resource skip mining in the order of this interval mining until only one mining shaft width W is left on this horizontal strip of coal seam. c When the coal seam on each horizontal strip undergoes two rounds of coal resource skipping, the filling sequence lags behind the skipping sequence by one mining shaft, that is, when the mining shaft A is completed and the mining shaft C is ready to be mined, the filling work of the mining shaft A is carried out; The filling material includes a first filling body and a second filling body, wherein the first filling body and the second filling body are filled at intervals from each other, that is, if the first filling body is used for filling in the mining shaft A and the mining shaft C, the second filling body is used for filling in the mining shaft B, and vice versa; when all the mining shafts on the same horizontal strip are mined, the filling strips formed by the first filling body and the second filling body at intervals from each other constitute the filling strip of this horizontal strip, and on this basis, the coal resources of the next horizontal strip are mined downward; In the vertical direction, when the filling strip of the previous horizontal strip is filled, when the coal resources of the next horizontal strip are mined, the mining holes at the two sides of the next horizontal strip need to be offset from the filling strips at the two sides of the previous horizontal strip by half the width of the mining hole 1 / 2W. c At the same time, the width of the permanent coal pillar on the previous horizontal strip and the permanent coal pillar on the next horizontal strip also differs by half the width of the mining tunnel, 1 / 2W. c ; Step 4) the main system performs floor breaking lowering arrangement processing of different degrees of underlying rock formations in the floor breaking area at the bottom of the pit, thereby mining coal in different horizontal strips of the coal seam; Step 5) Once the entire seam has been mined, a series of fill strips will form a "masonry wall" structure.

2. The method for backfilling and mining a thick coal seam at a high and steep slope according to claim 1, characterized in that: In step 4), the bottom plate breaking area has a minimum bottom plate breaking area width W according to the minimum operation size of the main system. min , the depth H of the bottom plate breaking area min It needs to be determined based on the stripping volume of the broken floor area, the length of coal / rock in the mining tunnel and the filling cost.

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