Solid waste internal circulation downward deep hole mining method for steeply inclined thin vein group

Abstract

The invention discloses a solid waste internal circulation downward deep hole mining method for a steeply inclined thin vein group. The method comprises the following steps that an ore body is divided into a plurality of middle sections, and the middle sections are divided into a plurality of panels; sequentially constructing an upper rock drilling drift and a top cutting chamber at the upper part of the ore body, and sequentially tunneling a middle section transportation roadway, an ore loading drift and a lower rock drilling drift at the lower part of the ore body; a rock drilling trench is constructed in the lower rock drilling drift, then a cutting raise is tunneled upwards, then a cutting vertical groove is constructed in the top cutting chamber, the cutting vertical groove is a free face, and lateral blasting is conducted to the panel boundary; the stoped ore slides to an ore removal access road through an ore collection trench at the bottom of the panel, is shoveled and conveyed into a panel draw shaft, and is conveyed for ore removal; after stoping of the whole panel is completed, stoping is conducted on the trench structure on the lower portion, and then overall filling of the panel is conducted; according to the method, the upward fan-shaped medium-length holes are adopted to form the bottom structure and cut the raise, and the downward parallel medium-length holes are adopted to positively discharge the lateral caving process to exploit the steeply inclined thin vein group, and large mechanical equipment is matched, so that the stage height is greatly increased, and the panel production capacity is improved.

Description

Technical Field

[0001] The invention relates to the technical field of mining, and in particular to a method for downward deep hole mining with internal circulation of solid waste in a group of steeply inclined thin ore veins. Background Art

[0002] Steeply inclined thin veins usually refer to those with an inclination angle greater than 55° and an ore body thickness of 0.2~4.0 m, which are often distributed in branch composites and vein groups. Thin veins account for more than 60% of the strategic mineral resources of rare precious metals. The veins are thin and thin, the mining space is limited, the blasting clamping effect is large and the effect is poor, and it is difficult to use large-scale mechanized equipment. Based on the mining experience of steeply inclined thin veins at home and abroad, at present, the mining of steeply inclined thin ore bodies mostly adopts shallow hole ore retention method, wall cutting and filling method, and upward horizontal layered filling method. Among them: the shallow hole ore retention method can better adapt to the changing ore body shape, but it has poor adaptability to medium-stable ore and rock, and has a high safety risk; when the ore body is thinner, the wall cutting and filling method is mostly used. However, during the mining process, the shallow hole ore retention method has a poor working environment and high labor intensity; the boundary control is difficult, the loss and dilution are high; the production capacity is small and the cost is high. If the ore rock is relatively broken locally, there will be great safety hazards. Although the upward layered filling method can effectively reduce the ore depletion loss rate and improve the stability of the surrounding rock of the stope, it has the disadvantages of low production capacity, many mining and approval projects, and high mining costs. There is also the use of medium-deep hole segmented mining of steeply inclined thin ore bodies, which has improved production capacity, but the numerous mining and approval projects and the resulting high depletion problem are inevitable.

[0003] The problems of the above-mentioned vein mining method are more obvious when mining steeply inclined thin vein groups. Therefore, it is particularly important to seek a mining system that can not only greatly improve the production capacity of the mine, but also reduce the ore depletion rate, improve the working environment, and ensure the safety of personnel for the mining of steeply inclined thin vein groups. Summary of the invention

[0004] In order to significantly increase the production capacity of the mine, reduce the ore depletion rate and improve the working environment, the present application provides a downward deep hole mining method for a group of steeply inclined thin ore veins with internal circulation of solid waste.

[0005] The present application provides a method for deep-hole mining with internal circulation of solid waste in steeply inclined thin ore veins, which adopts the following technical solution: A method for downward deep hole mining with internal circulation of solid waste in steeply inclined thin ore vein groups comprises the following steps: S1, the ore body is divided into multiple middle sections along the vertical direction, and the middle section is divided into multiple panel areas along the strike direction, and no intermediate pillars are left between the panel areas; S2, construct the upper rock drilling access and cut the top chamber in the upper part of the ore body, and excavate the middle transportation tunnel, ore loading access and lower rock drilling access in the lower part of the ore body; S3: construct a rock cutting trench in the lower rock drilling access at the end of the panel area, then excavate a cutting shaft upward from the rock cutting trench. After the cutting shaft is formed, construct a cutting groove in the cutting chamber, cut the groove into a free surface, and blast laterally to the panel area boundary; S4, after the recovered ore is crushed, it slides through the ore collecting trench at the bottom of the pan area to the mine entrance, and is shoveled into the pan area chute, slides into the ore solid waste internal circulation system and is transported out of the mine; S5. After the mining of the entire panel area is completed, the lower trench structure is first mined using medium-deep hole retreat method, and then the overall filling of the panel area is carried out.

[0006] Optionally, in step S1, the ore body is divided into a middle section every 40 to 50 m in the vertical direction, and the middle section is divided into a panel every 50 to 60 m along the strike direction, and each panel is gradually mined and filled.

[0007] Optionally, in step S2, in order to prevent the exposed area of ​​the connected chambers from being too large, pillars are retained between the cut-top chambers to support the roof.

[0008] Optionally, in step S2, the loading route should meet the turning radius requirements of the mining equipment, the angle between the loading route and the drilling route should be no less than 45°, and the spacing should be 8~10m to ensure that the bottom ore can be completely shoveled.

[0009] Optionally, in step S3, upward fan-shaped medium-deep holes are constructed and blasted to form rock cutting trenches, with a drilling diameter of 60-75 mm and a hole depth of 10-15 m; a blast hole row spacing of 1.2-1.5 m, a hole bottom distance of 1.6-2.0 m, and the blast holes parallel to the long axis direction of the cutting groove.

[0010] Optionally, in step S3, vertical parallel blast holes are drilled and blasted downward in the top cutting and rock drilling chamber to form cutting grooves.

[0011] Optionally, in step S3, during lateral blasting, the upward fan-shaped medium-deep holes should be blasted ahead of the corresponding downward parallel deep holes in the upper part. A single chamber is blasted for the first time, and two chambers are blasted each time thereafter. The charging structure of each hole in the lateral blasting is the same, and an interval uncoupled charging structure is adopted. The drilling diameter of the lateral blasting is φ165mm, and the hole depth is about 30~35m; the blasthole row spacing is 2.8~4.0m, the hole spacing is 3.0~4.0m, and the blasthole row surface is arranged parallel to the long axis direction of the cutting groove.

[0012] Optionally, in step S5, the ore in the chute is first coarsely crushed by a jaw crusher in the solid waste internal circulation system, and then vibrated and screened to screen out the ore smaller than 50 mm, and the ore larger than 50 mm is cone crushed. After screening, it enters the XRT intelligent ore dressing machine for intelligent photoelectric sorting. The sorted ore enters the powder ore bin and is lifted to the surface by a skip or transported to the surface by a belt conveyor. The sorted waste rock enters the waste rock bin and is used for underground waste rock filling and as aggregate for concrete.

[0013] In summary, this application includes the following beneficial technical effects: The present application uses upward fan-shaped medium-deep holes to form the bottom structure and cut the skylight, and downward parallel medium-deep holes to form a positive row of lateral caving technology to mine steeply inclined thin veins. In combination with large-scale mechanized equipment, the stage height is greatly increased, the production capacity of the panel area is improved, and the problem of poor blasting and clamping effect of thin veins is solved. Personnel drill rocks in the top cutting chamber and mine in the bottom structure, which effectively improves the on-site working environment, reduces the construction intensity of workers, avoids the safety risks of direct exposure to operations in the mining area, simplifies the mining system engineering in the middle section, and makes it easier to realize intelligent mining.

[0014] At the same time, by setting up an underground ore pre-selection and waste disposal system, the co-mining of waste rocks from thin vein groups is realized, and the effects of direct sorting of underground powder ore and internal recycling of solid waste are achieved. This effectively solves the problems of large depletion caused by deep hole blasting of thin vein groups and high economic cost of directly transporting the mined waste rocks out of the mine. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is an elevation view of a downward deep hole mining system with internal circulation of solid waste in a group of steeply inclined thin ore veins; Figure 2 It is a AA profile of a downward deep hole mining system with internal circulation of solid waste in a group of steeply inclined thin ore veins; Figure 3 It is a BB plan view of a downward deep hole mining system with internal circulation of solid waste in a group of steeply inclined thin ore veins; Figure 4 It is a CC plan view of a downward deep hole mining system with internal circulation of solid waste in a group of steeply inclined thin ore veins; Figure 5 It is the overall flow chart of the internal circulation system of ore solid waste.

[0016] Description of reference numerals: 1. Ore body; 2. Surrounding rock; 3. Downward parallel deep holes; 4. Upward fan-shaped medium and deep holes; 5. Loading access; 6. Off-vein transport tunnel; 7. Upper rock drilling access; 8. Cut-top chamber; 9. Lower rock drilling access; 10. Pan area chute; 11. Cutting shaft; 12. Backfill; 13. Ore blasted down; 14. Retained ore pillars; 15. Rock cutting trench. DETAILED DESCRIPTION

[0017] The following is combined with Figure 1-5 This application is described in further detail.

[0018] The present application embodiment discloses a method for deep-hole mining with internal circulation of solid waste in steeply inclined thin ore veins, the method comprising the following steps: S1. Divide the ore body into middle sections of 40~50m in the vertical direction, and divide the middle section into panels of 50~60m along the strike. No pillars are left between the panels, and each panel is mined and filled gradually.

[0019] S2. The upper rock drilling access 7 and the top-cutting chamber 8 are constructed in sequence on the upper part of the ore body. The dimensions of the access and the chamber should meet the requirements of the working space of the mining equipment and the down-the-hole drill rig respectively. In order to prevent the exposed area of ​​the chambers from being too large, a ore pillar 14 is retained between the top-cutting chambers to support the roof. The width of the ore pillar 14 should be no less than 3m. At the same time, the off-vein transport tunnel 6, the ore loading access 5 and the lower rock drilling access 7 are excavated in sequence in the lower part of the ore body. The ore loading access 5 should meet the requirements of the turning radius of the mining equipment, and the angle with the rock drilling access 7 should be no less than 45°. The distance between the accesses is generally 8~10m to ensure that the bottom ore can be completely shoveled.

[0020] S3. In the rock drilling access 7 at the end of the panel area, a rock drilling trolley is used to construct an upward fan-shaped medium-deep hole 4 to form a rock drilling trench 15, with a borehole diameter of 60-75 mm and a hole depth of 10-15 m; the blasthole row spacing is 1.2-1.5 m, the hole bottom distance is 1.6-2.0 m, and the blastholes are arranged parallel to the long axis direction of the cutting groove for blasting; then a cutting shaft 11 is excavated upward from the rock drilling trench 15, and the cross-section is generally 2×2 m. After the cutting shaft 11 is formed, a down-the-hole drill rig is used to drill downward vertical parallel blastholes 3 in the top cutting rock drilling chamber 8 to blast to form a cutting vertical groove, and this is used as a free surface for lateral blasting to the panel area boundary. The fan-shaped medium-deep hole 4 of the lower "V"-shaped trench should be blasted ahead of the corresponding downward parallel deep hole 3 in the upper part. During lateral blasting, a single chamber (2 rows of holes) is blasted for the first time, and then 2 chambers (4 rows of holes) are blasted each time. The charging structure of each hole in the lateral blasting is roughly the same, and an interval (axial) uncoupled charging structure is adopted to reduce the high powder ore rate, uneven block size, and high large block rate. The borehole diameter is φ165mm, and the hole depth is about 30~35m; the blasthole row spacing is 2.8~4.0m, the hole spacing is 3.0~4.0m, and the blasthole row surface is arranged parallel to the long axis direction of the cutting groove. The deep hole rock drilling adopts a stabilizer to prevent deviation, ensuring that the deep hole deviation rate should be less than 1% to obtain a better blasting effect, avoid the increase of secondary blasting costs, and greatly affect the mining efficiency of the mining field.

[0021] S4, the recovered ore 13 flows through the ore collecting trench at the bottom of the pan area to the ore loading access 5, and after the large pieces are processed by the mining hydraulic breaker, the ore is shoveled into the pan area chute 10 by the scraper, and the chute is covered with a 0.6×0.6m grid screen and flows into the ore solid waste internal circulation system; In the internal circulation system of ore solid waste, the ore of the chute is first crushed by a jaw crusher, and the material size is within 300mm. Then it is vibrated and screened to screen out ores less than 50mm. Ores larger than 50mm are crushed by hydraulic cone crushers, and the material size is generally 5~51mm. The above process is repeated until all ore fines are below 50mm. After screening, it enters the XRT intelligent concentrator for intelligent photoelectric sorting: it is fed to the belt through the feeding bin, and after reaching the X-ray sensing area, the ores of different densities are identified through X-ray transmission and sensor recognition imaging. The sensor sends instructions to the spray valve to spray the corresponding ore into the ore bin, and the waste rock directly enters the waste rock bin, so as to achieve the separation of useful minerals and waste rock. The ore in the powder ore bin is lifted by a bucket or transported to the surface by a belt; the waste rock in the waste rock bin is directly used for underground waste rock filling and as aggregate for concrete.

[0022] S5. After the entire panel area is mined, the lower rock cutting structure 15 adopts medium-deep hole retreat mining, and then the overall filling of the panel area is carried out.

[0023] Implementation case: The main veins of a lead-zinc mine are thin veins, with a thickness of about 2~4m, a spacing of 1~3m, and an average inclination of 70°. They are typical steeply inclined thin vein groups. The traditional shallow hole ore retention method is used for mining. The amount of waste rock recovered between the veins is large, causing great dilution. If single-vein mining is carried out, the stability of the upper plate roof is poor, which will pose a great threat to safe production. Therefore, the mine adopts a steeply inclined thin vein group solid waste internal circulation downward deep hole mining system. The system first forms a rock cutting trench by blasting upward fan-shaped holes in the lower part of the middle section, excavates a roof cutting chamber in the upper part, constructs downward parallel deep hole blasting, and mines in the rock cutting trench. Finally, it enters the solid waste internal circulation system to separate the ore waste, bring the powder ore to the surface, and recycle the waste rock underground. The system has been applied well in the mine, simplifying the middle mining system engineering, ensuring the safe mining of ore, greatly increasing the production capacity of the mine, and effectively solving the problems of large dilution of thin ore veins in deep hole blasting and high economic cost of directly transporting the mined waste rock out of the well. The main economic and technical indicators are: mine production capacity: 300~400t / d; ore recovery rate: 90~92%; ore dilution rate: 5%~8%; direct mining production cost: 80~110 yuan / t.

[0024] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A method for deep-hole mining with internal circulation of solid waste in steeply inclined thin ore veins, characterized in that The steps include: S1, the ore body is divided into multiple middle sections along the vertical direction, and the middle section is divided into multiple panel areas along the strike direction, and no intermediate pillars are left between the panel areas; S2, construct the upper rock drilling access and cut the top chamber in the upper part of the ore body, and excavate the middle transportation tunnel, ore loading access and lower rock drilling access in the lower part of the ore body; S3: construct a rock cutting trench in the lower rock drilling access at the end of the panel area, then excavate a cutting shaft upward from the rock cutting trench. After the cutting shaft is formed, construct a cutting groove in the cutting chamber, cut the groove into a free surface, and blast laterally to the panel area boundary; S4, after the recovered ore is crushed, it slides through the ore collecting trench at the bottom of the pan area to the mine entrance, and is shoveled into the pan area chute, slides into the ore solid waste internal circulation system and is transported out of the mine; S5. After the mining of the entire panel area is completed, the lower trench structure is first mined using medium-deep hole retreat method, and then the overall filling of the panel area is carried out.

2. The method for downward deep hole mining of a group of steeply inclined thin ore veins with solid waste internal circulation according to claim 1 is characterized by: In step S1, the ore body is divided into a middle section every 40 to 50 m in the vertical direction, and the middle section is divided into a panel every 50 to 60 m along the strike direction, and each panel is gradually mined and filled.

3. The method for downward deep hole mining of a steeply inclined thin ore vein group with internal circulation of solid waste according to claim 1, characterized in that: In step S2, in order to prevent the exposed area of ​​the connected chambers from being too large, pillars are left between the cut-top chambers to support the roof.

4. The method for downward deep hole mining of a group of steeply inclined thin ore veins with internal circulation of solid waste according to claim 3 is characterized by: In step S2, the loading route should meet the turning radius requirements of the mining equipment. The angle between the loading route and the rock drilling route should be no less than 45°, and the spacing should be 8-10m to ensure that the bottom ore can be completely shoveled.

5. The method for downward deep hole mining of a group of steeply inclined thin ore veins with internal circulation of solid waste according to claim 1, characterized in that: In step S3, upward fan-shaped medium-deep holes are constructed and blasted to form rock cutting trenches. The diameter of the drill hole is 60-75 mm, and the hole depth is 10-15 m. The blast hole row spacing is 1.2-1.5 m, the hole bottom distance is 1.6-2.0 m, and the blast holes are parallel to the long axis direction of the cutting groove.

6. The method for downward deep hole mining of a group of steeply inclined thin ore veins with solid waste internal circulation according to claim 5 is characterized by: In step S3, vertical parallel blast holes are drilled and blasted downward in the top cutting and rock drilling chamber to form cutting grooves.

7. The method for downward deep hole mining with internal circulation of solid waste in steeply inclined thin ore veins according to claim 6 is characterized by: In step S3, during lateral blasting, the upward fan-shaped medium-deep hole should be blasted ahead of the corresponding downward parallel deep hole at the top. A single chamber is blasted for the first time, and two chambers are blasted each time thereafter. The charging structure of each hole in the lateral blasting is the same, and an interval uncoupled charging structure is adopted. The diameter of the drill hole for lateral blasting is φ165mm, and the hole depth is about 30~35m. The blasthole row spacing is 2.8~4.0m, the hole spacing is 3.0~4.0m, and the blasthole row surface is arranged parallel to the long axis direction of the cutting groove.

8. The method for downward deep hole mining with internal circulation of solid waste in steeply inclined thin ore veins according to claim 1 is characterized by: In step S5, the ore in the chute is firstly coarsely crushed by a jaw crusher in the solid waste internal circulation system, and then vibrated and screened to screen out the ore smaller than 50 mm, and the ore larger than 50 mm is cone crushed. After screening, it enters the XRT intelligent ore dressing machine for intelligent photoelectric sorting. The sorted ore enters the powder ore bin and is lifted to the surface by a bucket or transported to the surface by a belt conveyor. The sorted waste rock enters the waste rock bin and is used for underground waste rock filling and as aggregate for concrete.

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