A mining method for gently inclined thick ore bodies taking into account the recovery of ore pillars in the panel area

Abstract

The present invention discloses a method for mining a gently inclined thick ore body that takes into account the recovery of panel pillars, and belongs to the field of mining technology. A method for mining a gently inclined thick ore body that takes into account the recovery of panel pillars comprises the following steps: S1, arranging two cutting lanes, one in the south and one in the north, on both sides of the mining area pillars, one of which is used as a cutting groove and the other as a mining tunnel; S2, adjusting the mining horizontal panel tunnel arranged in the center of the mining area pillars to the other side of the mining tunnel; S3, driving a connecting road to connect the mining horizontal panel tunnel with the mining tunnel and the panel chute respectively; S4, leaving a triangular ore pillar of a certain height above the mining tunnel to ensure the stability of mining; S5, when the pillars are recovered, constructing a mining access road between the mining horizontal panel tunnel and the mining tunnel, using the mining horizontal panel tunnel as a trench tunnel and the mining tunnel as a mining tunnel; the present invention solves the problem that the bottom structure of the panel pillars is difficult to arrange due to space limitations during the recovery process.

Description

Technical Field

[0001] The present invention relates to the field of mining technology, in particular to a mining method for a gently inclined thick ore body taking into account the recovery of ore pillars in a panel area. Background Art

[0002] Currently, in underground metal and non-metal mines, the primary method for recovering gently inclined, thick ore bodies is to use a one- or two-step process with staged stoping followed by backfill. This requires the installation of numerous pillars in the early stages of mining to ensure mining stability. During the recovery process, the narrow width of these pillars limits the layout of exit tunnels and access roads, making it difficult to establish a complete bottom ore-exit structure. This directly impacts the safety and resource recovery rate of pillar recovery.

[0003] For the mining of pan-area pillars, a flat-bottomed bottom structure is generally adopted at the mining level. In order to ensure the safety of mining operations, the flat-bottomed structure needs to use a remote-controlled scraper to mine. However, due to the large height of the mining area and the susceptibility of the pan-area pillars to excavation and blasting disturbances on both sides of the mining area, the stability of the ore rock is weakened, and there is a risk of roof collapse and ore pile collapse that buries equipment, and large blocks are difficult to handle.

[0004] The paper "Application and Practice of Safe and Efficient Recovery Technology for Residual Ore and Bottom Pillars at the Bottom of a Polymetallic Mine Goaf" proposes a technical solution in which trenches are further arranged within the horizontal pillars at the bottom of the trench to form a bottom structure of upper and lower trenches. However, this requires the reconstruction of connecting tunnels, which results in large excavation workload and investment, and will affect the stability of the horizontal pillars and their subsequent recovery.

[0005] The paper "Research on Optimization of the Bottom Structure of a Two-Step Stope in a Gently Inclined Thick Orebody Pan" proposes a bottom structure scheme for tunneling trenches within the backfill. This scheme can fully utilize the existing project and has a relatively low engineering workload. However, it requires tunneling within the backfill, which makes construction difficult, the backfill strength does not meet the requirements, and the support cost is high.

[0006] In response to the above problems, there is an urgent need to develop a mining method suitable for gently inclined thick ore bodies that can take into account the recovery of ore pillars in the panel area and facilitate the arrangement of the "V"-shaped trench bottom structure. Summary of the Invention

[0007] The purpose of the present invention is to solve the problems existing in the prior art and to propose a mining method for a gently inclined thick ore body taking into account the recovery of ore pillars in the panel area.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] A method for mining a gently inclined thick ore body while taking into account the recovery of ore pillars in the panel area, comprising the following steps:

[0010] S1. Two cutting lanes are arranged on both sides of the mining pillar in the mining area, which are at the same level and parallel to the horizontal panel area connecting lanes of the mining area. One of them is used as a cutting groove and the other is used as a mining connecting lane.

[0011] S2. Adjust the mining horizontal panel tunnel arranged in the center of the mining pillar to the other side of the mining tunnel;

[0012] S3, excavate the connecting road to connect the horizontal panel area tunnel with the mine roadway and the panel area chute;

[0013] S4. A triangular pillar is set above the mining tunnel at a certain height to ensure the stability of the mining;

[0014] S5. When recovering the ore pillars, according to relevant parameters, a mine access road is constructed between the mine level panel area connecting tunnel and the mine connection tunnel, with the mine level panel area connecting tunnel as the trench tunnel and the mine connection tunnel as the mine tunnel.

[0015] Preferably, the mining connecting tunnel in step S1 connects the mining tunnel and the stope trench tunnel, serves as a rock drilling and blasting operation channel and mining access road during mining, and serves as a mining tunnel when the mining area pillars are recovered in the later stage.

[0016] Preferably, the position of the mining horizontal panel connecting tunnel in step S2 should be adjusted so that the distance between it and the mining connecting tunnel meets the minimum requirement for the layout of the mining access route.

[0017] Preferably, the horizontal panel tunnel in step S3 serves as a transportation tunnel for rock drilling and ore discharge during mining, and serves as a trench tunnel during the recovery of panel pillars in the later stage.

[0018] Preferably, the triangular pillars set in step S4 should be modeled by computer software based on the actual conditions of the mine to simulate the ore-falling conditions to obtain the thickness of the triangular pillars required to maintain the stability of the mining tunnel. Then, based on the slope angle of the triangular pillars and the specification parameters of the mining tunnel, the height of the triangular pillars required to maintain the stability of the mining tunnel is calculated through geometric relationships.

[0019] Preferably, the relevant parameters mentioned in step S5 include: the distance between the mining access roads, the intersection angle between the mining access roads and the mining connecting tunnels, the length of the mining access roads, the cross-sectional specifications of the mining access roads and the slope angle of the V-shaped trench.

[0020] Preferably, the length of the mine access road is determined by the basic requirements for normal operation of the scraper and construction of the filling retaining wall.

[0021] Preferably, the length L of the mine access road that meets the requirements of the shovel loader is determined by the ore inflow length L1 in the mine access road and the distance L2 of the straight section of the access road, L=L1+L2; the length L of the mine access road that meets the requirements of building a filling retaining wall is determined by the mine eyebrow line protection length L3, the curve length L4 from the mine connecting tunnel to the mine access road and the filling retaining wall construction length L5, L=L3+L4+L5, and the larger value of the two is taken as the length of the mine access road.

[0022] Preferably, the cross-sectional specifications of the trench tunnel, mine access road and mine connecting tunnel in the parameters of step S5 are all 4.8m×3.8m, the distance between the mine access roads is 12m~15m, the intersection angle between the mine access road and the mine connecting tunnel is 40°~50°, and the V-shaped trench slope angle is 50°.

[0023] Preferably, the distance between the mining horizontal panel tunnel and the mining tunnel is obtained through geometric relationship according to the length L of the mining access road and the intersection angle between the mining access road and the mining tunnel.

[0024] Compared with the existing technology, the present invention provides a method for mining gently inclined thick ore bodies while taking into account the recovery of ore pillars in the panel area, which has the following beneficial effects:

[0025] 1. This method for mining gently inclined thick ore bodies that takes into account the recovery of panel pillars is to arrange two cutting tunnels, one in the south and one in the north, on both sides of the mining area pillars. One of them is used to construct the cutting groove, and the other is retained as the mining tunnel for future mining area pillar recovery. The mining horizontal panel connecting tunnel arranged in the center of the mining area pillar is adjusted to the other side of the mining tunnel. The distance between the panel connecting tunnel and the mining tunnel meets the requirements of the mining access road, which solves the problem that the mining tunnel and the mining access road cannot be constructed simultaneously due to space limitations when recovering the mining area pillars, and it is not convenient to use a "V"-shaped trench bottom structure.

[0026] 2. This mining method for gently inclined thick ore bodies that takes into account the recovery of ore pillars in the pan area ensures the stability of ore production by leaving triangular ore pillars of a certain height on the upper part of the ore-exit tunnel.

[0027] 3. This method of mining gently inclined thick ore bodies that takes into account the recovery of ore pillars in the panel area reduces the amount of work during the mining of ore pillars in the panel area, saves mining costs, and improves mining efficiency by making full use of the mining project arranged in the first step of the mining site. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A front view of a mining plan for a stope recovery step provided by the present invention;

[0029] Figure 2 for Figure 1 Schematic diagram of the cross section along the II-II direction;

[0030] Figure 3A front view of the mining plan for recovering ore pillars provided by the present invention;

[0031] Figure 4 for Figure 3 Schematic diagram of the cross section along the middle IV-IV direction;

[0032] Figure 5 A schematic diagram of the height calculation for the triangular pillar is provided;

[0033] Figure 6 for Figure 5 Schematic diagram of the cross section in the VI-VI direction.

[0034] In the figure: 1. Horizontal drilling area connecting tunnel; 2. Horizontal mining area connecting tunnel; 3. Area chute; 4. Drilling tunnel; 5. Mining tunnel; 6. Cutting tunnel; 7. Mining tunnel; 8. Mining access road; 9. Mining trench tunnel; 10. Mining area pillar; 11. Triangular pillar; 12. Horizontal intermediate pillar. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0036] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0037] Example: See Figure 1-5 The present embodiment provides a method for mining a gently inclined, thick, and large ore body while taking into account the recovery of ore pillars in the panel area, specifically comprising the following steps:

[0038] (1) In this embodiment, the mining area pillar 10 is set with a width of 18m. Two cutting tunnels 6 are arranged on both sides of the mining area pillar 10, which are located at the same level as the mining horizontal panel area connecting tunnel 2 and are parallel to the mining horizontal panel area connecting tunnel 2. One is used as a cutting groove and the other is used as a mining connecting tunnel 5. The cross-sectional specifications of both are 4.8m×3.8m. Figure 1-2 shown.

[0039] (2) The horizontal plate area connecting tunnel 2 arranged in the center of the mining area pillar 10 is adjusted to the other side of the mining connecting tunnel 5 so that the distance between it and the mining connecting tunnel 5 meets the requirements for the layout of the mining access road 8. The length of the mining access road 8 is determined by the normal operation of the scraper and the basic requirements for the construction of the filling retaining wall.

[0040] Depend on Figure 6 As shown in a, the length L of the ore outlet route 8 that meets the requirements of the scraper is determined by the ore inflow length L1 in the ore outlet route 8 and the straight section distance L2 of the route, L=L1+L2; Figure 6 As shown in FIG. 2 , the length L of the mining access road 8 that meets the requirements for the construction of the filling retaining wall is determined by the protection length L3 of the mining eyebrow line, the length L4 of the curve from the mining connecting tunnel 5 to the mining access road 8, and the construction length L5 of the filling retaining wall. L=L3+L4+L5. The larger value of the two is taken as the length of the mining access road 8. In this embodiment, the length of the mining access road 8 is 11.1m.

[0041] Then, based on the fact that the length of the mining access road 8 is 11.1m and the intersection angle between the mining access road 8 and the mining connecting tunnel 5 is 40°~50°, the distance between the mining horizontal panel connecting tunnel 2 and the mining connecting tunnel 5 is 8m through geometric relationships.

[0042] (3) If Figure 2 、 Figure 4 As shown, the connecting road is excavated to connect the horizontal panel area connecting tunnel 2 with the mining tunnel 7 and the panel area chute 3 respectively. The horizontal panel area connecting tunnel 2 of the mining is used as a transportation tunnel for rock drilling and ore discharge during the first step of mining, and as a trench tunnel when the mining area pillars 10 are recovered in the later stage. The cross-sectional specifications are 4.8m×3.8m.

[0043] (4) If Figure 2 、 Figure 4 As shown, the mining connecting tunnel 5 connects the mining tunnel 7 and the mining trench tunnel 9, serving as the rock drilling and blasting operation channel and the mining access road 8 during the first step of mining, and serving as the mining tunnel 7 when the mining pillars 10 are recovered in the later stage.

[0044] (5) A triangular pillar 11 of a certain height is set above the mining tunnel 5. According to the actual situation of the mine, a model is constructed using software such as FLAC3D to simulate the ore falling conditions. The thickness d of the pillar required for the mining tunnel 5 to maintain stability is obtained. Then, based on the slope angle of the triangular pillar 11, the specifications of the mining tunnel 5 and other parameters, the required height h of the triangular pillar 11 can be calculated to be 8~10m through geometric relationships. For details, see Figure 5 .

[0045] (6) If Figure 3 、 Figure 4 As shown, when the ore pillars are recovered, a mine access road 8 is constructed between the mine horizontal panel area connecting tunnel 2 and the mine access road 5, with the mine horizontal panel area connecting tunnel 2 as the trench tunnel, and the mine access road 5 as the mine access road 7. The cross-sectional specifications of the trench tunnel, the mine access road 8 and the mine access road 7 are all 4.8m×3.8m, the spacing between the mine access roads 8 is 12m~15m, the intersection angle between the mine access road 8 and the mine access road 7 is 40°~50°, and the V-shaped trench slope angle is 50°.

[0046] The present application arranges two cutting tunnels 6, one in the south and the other in the north, on both sides of the mining pillar 10 in the mining area, one of which is used for constructing the cutting groove, and the other is retained as the mining tunnel 7 for recovering the mining pillar 10 in the future, and adjusts the mining horizontal disk area connecting tunnel 2 arranged in the center of the mining pillar 10 to the other side of the mining tunnel 5. The distance between the mining horizontal disk area connecting tunnel 2 and the mining tunnel 5 meets the requirements of the mining access road 8, which solves the problem that the mining tunnel 7 and the mining access road 8 cannot be constructed at the same time due to space limitations when recovering the mining pillar 10 in the mining area, and it is not convenient to adopt a "V"-shaped trench bottom structure. By leaving a triangular mining pillar 11 of a certain height on the upper part of the mining tunnel 5, the mining stability is guaranteed, the mining preparation project arranged in the mining site is fully utilized, the engineering workload during the mining of the mining pillar 10 in the mining area is reduced, the mining cost is saved, and the mining efficiency is improved.

[0047] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A method for mining a gently inclined, thick, and large ore body while taking into account the recovery of ore pillars in the panel area, characterized in that: The following steps are involved: S1. Two cutting lanes (6) are arranged on both sides of the mining area pillar (10), which are located at the same level as the mining horizontal panel area connecting lane (2) and are parallel to the mining horizontal panel area connecting lane (2), one of which is used as a cutting groove and the other is used as a mining connecting lane (5); S2, adjusting the mining horizontal panel area joint tunnel (2) arranged in the center of the mining area pillar (10) to the other side of the mining joint tunnel (5); S3, excavating a connecting road to connect the mine-exit horizontal panel area connecting roadway (2) with the mine-exit roadway (7) and the panel area chute (3); S4. A triangular pillar (11) is set above the mining tunnel (5) at a certain height to ensure the stability of the mining; S5. When the ore pillars are recovered, according to relevant parameters, a mine access road (8) is constructed between the mine level panel area joint tunnel (2) and the mine level panel area joint tunnel (5), with the mine level panel area joint tunnel (2) serving as the trench tunnel and the mine level panel area joint tunnel (5) serving as the mine tunnel (7); The relevant parameters mentioned in step S5 include: the spacing of the mining access road (8), the intersection angle between the mining access road (8) and the mining connecting tunnel (5), the length of the mining access road (8), the cross-sectional specifications of the mining access road (8) and the V-shaped trench slope angle; The length of the mine access road (8) is determined by the basic requirements of the normal operation of the scraper and the construction of the filling retaining wall; The length L of the mining access road (8) that meets the requirements of the scraper is determined by the ore inflow length L1 in the mining access road (8) and the distance L2 of the straight section of the access road, L=L1+L2; the length L of the mining access road (8) that meets the requirements of the construction of the filling retaining wall is determined by the mining eyebrow line protection length L3, the curve length L4 from the mining connecting tunnel (5) to the mining access road (8) and the filling retaining wall construction length L5, L=L3+L4+L5, and the larger value of the two is taken as the length of the mining access road (8); The parameters in step S5 are that the cross-sectional specifications of the trench tunnel, the mining access road (8) and the mining joint tunnel (5) are all 4.8m×3.8m, the spacing of the mining access road (8) is 12m~15m, the intersection angle between the mining access road (8) and the mining joint tunnel (5) is 40°~50°, and the V-shaped trench slope angle is 50°.

2. A method for mining a gently inclined, thick, and large ore body while taking into account the recovery of ore pillars in the panel area according to claim 1, characterized in that: The mining tunnel (5) in step S1 connects the mining tunnel (7) and the mining trench tunnel (9), and serves as a rock drilling and blasting operation channel and a mining access road (8) during mining, and serves as a mining tunnel (7) when the mining area pillars (10) are recovered in the later stage.

3. The method for mining a gently inclined, thick, and large ore body while taking into account the recovery of ore pillars in the panel area according to claim 1, characterized in that: The position of the mining horizontal panel area connecting tunnel (2) in step S2 should be adjusted so that its distance from the mining connecting tunnel (5) meets the minimum requirement for the layout of the mining access road (8).

4. The method for mining a gently inclined, thick, and large ore body while taking into account the recovery of ore pillars in the panel area according to claim 1, characterized in that: The horizontal panel-area connecting tunnel (2) in step S3 serves as a transportation tunnel for rock drilling and ore removal during mining, and serves as a trench tunnel during the recovery of panel-area ore pillars in the later stage.

5. The method for mining a gently inclined, thick, and large ore body while taking into account the recovery of ore pillars in the panel area according to claim 1, characterized in that: The triangular pillar (11) set in step S4 should be constructed based on the actual situation of the mine through computer software to simulate the ore-falling conditions to obtain the thickness of the triangular pillar (11) required for the ore-exit tunnel (5) to maintain stability. Then, based on the slope angle of the triangular pillar (11) and the specification parameters of the ore-exit tunnel (5), the height of the triangular pillar (11) required to maintain the stability of the ore-exit tunnel (5) is calculated through geometric relationships.

6. The method for mining a gently inclined, thick, and large ore body while taking into account the recovery of ore pillars in the panel area according to claim 1, characterized in that: According to the length L of the mining access road (8) and the intersection angle between the mining access road (8) and the mining joint tunnel (5), the distance between the mining horizontal panel joint tunnel (2) and the mining joint tunnel (5) is obtained through geometric relationship.

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