Sublevel open stope and fill mining method

Abstract

The segmented open-cut mining method involves first dividing the ore body next to the collapsed waste rock into a single stope. Then, the stope is further divided into sections based on height. Within each section, drilling tunnels are constructed along the strike. On the side of the stope closest to the waste rock, a 6-8 meter wide ore body is left as a temporary waste rock isolation pillar. The ore body is then blasted back into the stope using the segmented open-cut method. A remotely controlled loader enters the goaf and removes the clean ore. By adjusting the orifice parameters and increasing the explosive charge, the temporary waste rock isolation pillar is blasted and thrown to the other side of the goaf. A 45° waste rock slope is formed. Finally, a remote-controlled loader is used to enter the goaf through the access road to complete the ore extraction and then perform low-intensity backfilling on the goaf. After the entire segment is mined, the process turns to the next segment until the ore body is mined out. The bottom passage of the goaf is closed, and the goaf is filled with low-intensity backfilling and high-intensity rubber surface to ensure the roof is sealed. This provides a safe and reliable working platform for the next segment of mining. It has the advantages of solving the safety problem of adjacent mining areas under the adverse effects of goaf collapse and waste rock, and reducing lean loss and mining costs.

Description

Technical Field

[0001] This invention relates to the field of metal mining technology, and in particular to a segmented open-field throwing followed by backfilling mining method, which is suitable for safe, low-loss, and low-cost mining of ore bodies next to waste rock. Background Technology

[0002] When unstable ore bodies are mined using the open-cut or subsequent backfilling method, the roof and hanging wall of the goaf are prone to collapse, resulting in waste rock filling the goaf. High-strength tailings are typically used to cement the collapsed waste rock in the goaf before mining adjacent stops. However, even with high-strength tailings, it is difficult to effectively cement the loose waste rock, especially when the collapsed loose rock in the goaf is a fractured zone. Due to its small particle size or clay-like texture, tailings backfilling is difficult to cement, and waste rock is easily mixed in during the mining of adjacent stops, causing significant dilution, losses, and safety hazards. In this case, pillars need to be left in adjacent stops to ensure the safety of mining adjacent ore bodies and prevent the mixing (dilution) of collapsed waste rock from the goaf. The loss of these pillars is generally 20-30%, which represents a huge waste of resources and economic loss for mining high-value ore sections.

[0003] To address the aforementioned issues, Chinese patent CN 107165635 U discloses "A Sloping Throwing Blasting Mining Method for Gently Dipping Thin Ore Bodies," which aims to solve the problem of high dilution rates during the mining of gently dipping thin ore bodies. However, it is prone to roof collapse due to blasting, leading to significant ore dilution. It does not address the problem of poor safety conditions and high dilution losses in adjacent stopes under the adverse hazards of landslides and waste rock. Chinese patent CN 109812268 B discloses "Mechanized Upward Horizontal Layered Filling Roof Pillar Directional Throwing Blasting Mining Method for Panels," which aims to solve the significant safety hazards associated with personnel and loader entry into the stope during roof pillar recovery. However, it does not address the problem of poor safety conditions and high dilution losses in adjacent stopes under the adverse hazards of landslides and waste rock. Chinese patent CN 108825239... B disclosed "a mining method to reduce the waste rock mixing rate", aiming to solve the problem of high and difficult-to-control waste rock mixing rate when mining under waste rock overburden strata. However, it did not describe the mining problem of poor safety conditions and large dilution losses in adjacent mining areas under the adverse hazards of landslide waste rock.

[0004] Therefore, it is of great significance to develop a segmented open-hole dumping and subsequent backfilling mining method that can solve the adverse effects of goaf collapse and waste rock on the safe, low-loss, and low-cost mining of adjacent ore bodies. Summary of the Invention

[0005] The objective of this invention is to overcome the shortcomings of existing technologies and provide a segmented open-hole dumping followed by backfilling mining method. This method can solve the safety problem of adjacent ore bodies under the adverse effects of goaf collapse and waste rock, and also reduce mineral loss and mining costs.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] The segmented open-cut mining method, followed by backfilling, involves first dividing the ore body next to the collapsed waste rock into 46-56m long sections, then further dividing each section into 12.5-15m high segments. Within each segment, drilling tunnels are constructed along the strike. A 6-8m wide section of ore body is left on the side of the stope closest to the waste rock as a temporary waste rock isolation pillar. Under the protection of this pillar, a 40-50m long section of ore body is blasted back using the segmented open-cut method. A remotely controlled loader enters the goaf to remove clean ore. The explosive charge is then increased using small-aperture parameters, and the temporary waste rock isolation pillar is blasted and thrown using a throwing blasting method. Approximately 12 meters away from the waste rock, on the other side of the goaf, a 45° waste rock slope is formed. This minimizes the amount of waste rock mixed into the goaf after the temporary waste rock isolation pillar is mined. Finally, a remote-controlled loader is used to enter the goaf through the access road to complete ore extraction and then perform low-intensity backfilling. After the entire segment is mined, the process moves to the next segment until the ore body is completely mined. After the mining is completed, the bottom passage of the goaf is sealed, and the goaf is filled with low-intensity backfilling and high-intensity rubber lining is used to ensure a stable roof, providing a safe and reliable working platform for the next segment. The specific steps and conditions for the next segment's mining are as follows:

[0008] A. Divide the ore body next to the collapsed waste rock into 46-56m sections, each section being further divided into segments of 12.5-15m height. Within each segment, construct drilling tunnels along the strike. Initially, leave a 6-8m wide section of ore body near the waste rock as a temporary waste rock isolation pillar. Under the protection of this pillar, use the sublevel open-cut method to blast back 40-50m of ore body from the stope. Remotely controlled loaders enter the goaf to remove clean ore, and then... By increasing the amount of explosives with small-aperture mesh parameters, the temporary waste rock isolation pillar is blasted and thrown to the other side of the goaf about 12m away from the waste rock, forming a 45° waste rock slope. This can minimize the amount of collapsed waste rock mixed in after the temporary waste rock isolation pillar is mined out. Finally, a remote-controlled loader is used to enter the goaf through the access road to complete the ore extraction. The goaf is then filled with low-intensity filling. After the entire section is mined out, the process turns to mining the next section until the ore body is mined out.

[0009] B. A ore body approximately 6-8 meters wide is temporarily left on the side near the collapsed waste rock as a temporary waste rock isolation pillar;

[0010] C. Construct rock drilling tunnels along the strike within the segment, and construct ore extraction access roads in the footing;

[0011] D. Construct a cutting cross passage at the end of the mining area, and construct a cutting riser at one end of the cutting cross passage;

[0012] E. For ore bodies 40-50m long in the stope, drill fan-shaped medium-deep holes, using the cutting riser as a free face and compensation space to form a cutting groove at the end of the stope. Then, use the cutting groove as a free face and supplementary space for forward mining. Each caving step is 5-6 rows, and retreat mining is carried out to the temporary waste rock isolation pillar in the stope.

[0013] F. During stope ventilation, fresh air enters the stope from the section roadway, ore exit roadway, or drilling roadway. Waste air from cleaning the working face is discharged from the other end of the stope or the upper section connecting roadway to the return airway, and then discharged to the surface via the ventilation shaft and return airway. A 1m... 3 The remote-controlled loader enters the goaf area or exits the mine through the ore exit route, loads the ore and dumps it into the nearest pass to enter the transportation section and transport it to the surface;

[0014] G. After the mining area is mined out, a goaf is formed. For temporary waste rock isolation pillars, small hole mesh parameters are used to increase the amount of explosives and throw the temporary waste rock isolation pillars into the goaf about 12m away from the waste rock in one blast, forming a 45° waste rock slope. When the height of the 12m segment is 12m, its length is about 12m, which can minimize the mixing of waste rock during the mining process of temporary waste rock isolation pillars.

[0015] H. After ventilation, a remote-controlled shovel is used to enter the goaf through the ore exit roadway to ore out of the goaf. The ore is shoveled and dumped into a nearby ore pass, and then transported to the surface via the intermediate transport section.

[0016] Compared with the prior art, the present invention has the following advantages or effects:

[0017] (1) Because by leaving small-sized temporary waste rock isolation pillars at the ore body and waste rock, the losses and dilution caused by waste rock mixing into the mining area during the mining process of most of the ore body can be reduced, so the mining recovery rate of the mining area excluding the temporary waste rock isolation pillars can be increased to more than 96%.

[0018] (2) At the same time, by using small hole mesh parameters to increase the amount of explosives and throwing blasting method to blast the temporary waste rock isolation pillar to the other side of the goaf far away from the waste rock, the waste rock mixed into the ore after the temporary waste rock isolation pillar is mined out is reduced, and the ore is mined out by remote-controlled shovel and loader. The recovery rate of the temporary waste rock isolation pillar can reach more than 90%.

[0019] (3) In addition, by dividing the ore body into multiple segments and then filling the open space in the segments, the mining method can improve the stability of the mining area on the one hand, and the segmented mining can effectively control the distance of waste rock sliding into the mining area on the other hand, so it can control the loss and dilution of the mining area and improve the economic benefits of mining, especially for the mining of rare and precious high-value ore bodies.

[0020] In summary, this method enables safe, reliable, low-loss, and low-cost mining of adjacent stops under the influence of sidewall collapse and waste rock. The goaf, filled with loose material due to roof or hanging wall collapse, presents significant technical challenges for adjacent stopes. Specifically, it addresses the poor cementing effect of high-strength tailings cemented backfilling of loose material in the goaf (especially when it consists of fine clay particles). It also addresses the necessity of maintaining a certain thickness of safety pillars (with pillar losses typically between 20% and 30%) to prevent loose material from the collapse waste rock from mixing into adjacent stops, thereby improving the recovery rate and economic benefits of adjacent stops. Furthermore, the method utilizes a remote-controlled loader to enter the goaf via an access road to extract ore and subsequently perform low-strength backfilling. After the entire sub-section is mined, the process shifts to the next sub-section until the ore body is completely mined. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a segmented open-field throwing followed by backfilling mining method proposed in this invention.

[0022] Figure 2 yes Figure 1 The method shown is illustrated in a side view.

[0023] Figure 3 yes Figure 1 The method shown is illustrated from above.

[0024] The symbols in the attached diagram represent:

[0025] 1. Transport roadway 2. Through-vein 3. Sectional roadway 4. Ore exit roadway 5. Rock drilling roadway 6. Throwing blast hole 7. Goaf 8. 45° waste rock slope 9. Waste rock 10. Tailings backfill 11. Temporary waste rock isolation pillar

[0026] The present invention will now be described in further detail with reference to the accompanying drawings. Detailed Implementation

[0027] like Figure 1-3As shown, the segmented open-pit dumping and subsequent backfilling mining method first divides the ore body next to the collapsed waste rock into a stope with a length of 46-56m. Then, the stope is divided into sections with a height of 12.5-15m. Within each section, a drilling tunnel (5) is constructed along the strike. On the side of the stope near the waste rock, an ore body of about 6-8m width is left as a temporary waste rock isolation pillar (11). Under the protection of the temporary waste rock isolation pillar (11), the ore body of 40-50m length in the stope is blasted back using the segmented open-pit method. A remote-controlled loader enters the goaf to shovel out clean ore. The amount of explosive is increased by adjusting the small hole mesh parameters, and the temporary waste rock isolation pillar is blasted and thrown into the goaf using the dumping blasting method. On the other side of the goaf about 12m away from the waste rock, a 45° waste rock slope (8) is formed, which can minimize the amount of collapsed waste rock (9) mixed in after the temporary waste rock isolation pillar (11) is mined. Finally, a remote-controlled loader is used to enter the goaf (7) through the access road to complete the ore extraction and then carry out low-intensity backfilling of the goaf (7). After the entire segment mining is completed, the mining will turn to the previous segment until the ore body is mined. After the mining is completed, the bottom passage of the goaf is closed, the goaf is filled with low-intensity backfilling, and high-intensity rubber surface is used to ensure the roof is sealed, providing a safe and reliable working platform for the mining of the previous segment. At this point, the mining of the previous segment will begin. The specific steps and conditions are as follows:

[0028] A. Divide the ore body next to the collapsed waste rock into a stope of 46-56m. Divide the stope into sections of 12.5-15m in height. Drilling tunnels (5) are constructed along the strike within each section. First, leave an ore body of about 6-8m width on the side of the stope near the waste rock as a temporary waste rock isolation pillar (11). Under the protection of the temporary waste rock isolation pillar (11), the ore body of 40-50m length in the stope is blasted back using the segmented open field method. The remote-controlled loader enters the goaf area (7) to scoop out the clean ore. Then, through a small The parameters of the hole mesh are increased to increase the amount of explosives. The temporary waste rock isolation pillar is blasted and thrown to the other side of the goaf (7) about 12m away from the waste rock to form a 45° waste rock slope (8). This can minimize the amount of collapsed waste rock (9) mixed in after the temporary waste rock isolation pillar (11) is mined. Finally, a remote-controlled loader is used to enter the goaf (7) through the access road to complete the ore extraction. The goaf is then filled with low-intensity filling. After the entire section is mined, the mining is turned to the next section until the ore body is mined.

[0029] B. A ore body approximately 6-8m wide is temporarily left on the side near the collapsed waste rock (9) as a temporary waste rock isolation pillar (11);

[0030] C. Construct a rock drilling tunnel (5) along the strike within the segment, and construct the ore extraction access road (4) in the footing;

[0031] D. Construct a cutting cross passage at the end of the mining area, and construct a cutting riser at one end of the cutting cross passage;

[0032] E. For ore bodies 40-50m long in the mining area, drill fan-shaped medium-deep holes, use the cutting riser as the free surface and compensation space, form a cutting groove at the end of the mining area, and then use the cutting groove as the free surface and supplementary space for forward mining. Each caving step distance is 5-6 rows, and retreat mining is carried out to the temporary waste rock isolation pillar in the mining area (11).

[0033] F. During mine ventilation, fresh air enters the mine through the section roadway (3), the ore exit roadway (4), or the drilling roadway (5). Waste air from cleaning the working face is discharged from the other end of the mine or the upper section connecting roadway to the return airway, and then discharged to the surface through the ventilation shaft and return airway. A 1m... 3 The remote-controlled shovel enters the goaf area or exits the mine through the ore exit (4), loads the ore and dumps it into the nearest chute to enter the transportation section and transport it out to the surface;

[0034] G. After the mining area is mined, a goaf is formed. For the temporary waste rock isolation pillar (11), the explosive amount is increased by using small hole mesh parameters and throwing blasting method to blast the temporary waste rock isolation pillar (11) in one go to the other side of the goaf about 12m away from the waste rock to form a 45° waste rock slope (8). When the 12m segment height is 12m, its length is about 12m, which can minimize the mixing of waste rock (9) during the mining process of the temporary waste rock isolation pillar (11).

[0035] H. After ventilation, a remote-controlled shovel is used to enter the goaf area (7) through the ore exit road to ore out, load the ore into the nearby chute, and transport it out to the surface through the transportation section.

[0036] The process of the present invention can be further described as follows:

[0037] The length of the 45° waste rock slope (8) formed in step A is within 10m.

[0038] The rock drilling tunnel (5) and the ore extraction roadway (4) in step C adopt a flat-bottom structure, which facilitates the remote control of the shovel and loader to enter the mining area for ore extraction.

[0039] Step E involves drilling using a YGZ-90 drilling rig or a Simba 1354 drilling rig.

[0040] As described above, the present invention can be well implemented. The above embodiments are only the best implementations of the present invention, but the implementation of the present invention is not limited to the above embodiments. Other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention should be considered equivalent substitutions and are all included within the protection scope of the present invention.

Claims

1. A segmented open-field throwing followed by backfilling mining method, characterized in that... First, the ore body next to the collapsed waste rock is divided into a stope with a length of 46-56m. Then, the stope is divided into a segment with a height of 12.5-15m. Within the segment, a drilling tunnel (5) is constructed along the strike. A 6-8m wide ore body is left on the side of the stope near the waste rock as a temporary waste rock isolation pillar (11). Under the protection of the temporary waste rock isolation pillar (11), the ore body with a length of 40-50m in the stope is blasted back using the segmented open field method. A remote-controlled loader enters the goaf to shovel out clean ore. The amount of explosive is increased by adjusting the small hole mesh parameters. The temporary waste rock isolation pillar is blasted and thrown to a stope 12m away from the waste rock. On the other side of the goaf, a 45° waste rock slope (8) is formed, which can minimize the amount of collapsed waste rock (9) mixed in after the temporary waste rock isolation pillar (11) is mined. Finally, a remote-controlled loader is used to enter the goaf (7) through the access road to complete the ore extraction and then carry out low-intensity backfilling of the goaf (7). After the entire segment mining is completed, the mining will turn to the previous segment until the ore body is mined. After the mining is completed, the bottom passage of the goaf is closed, the goaf is filled with low-intensity backfilling, and high-intensity rubber surface is used to ensure the roof is sealed, providing a safe and reliable working platform for the mining of the previous segment. At this point, the mining of the previous segment will begin. The specific steps and conditions are as follows: A. Divide the ore body next to the collapsed waste rock into a stope of 46-56m. Divide the stope into sections of 12.5-15m in height. Drilling tunnels (5) are constructed along the strike within each section. First, leave a 6-8m wide ore body on the side of the stope near the waste rock as a temporary waste rock isolation pillar (11). Under the protection of the temporary waste rock isolation pillar (11), the ore body of 40-50m in length of the stope is blasted back using the segmented open field method. The remote-controlled loader enters the goaf (7) to scoop out the clean ore. Then, through a small The parameters of the hole mesh are increased to increase the amount of explosives. The temporary waste rock isolation pillar is blasted and thrown to the other side of the goaf (7) 12m away from the waste rock to form a 45° waste rock slope (8). This can minimize the amount of collapsed waste rock (9) mixed in after the temporary waste rock isolation pillar (11) is mined. Finally, the remote-controlled loader is used to enter the goaf (7) through the access road to complete the ore extraction. The goaf is then filled with low-intensity filling. After the entire section is mined, the mining is turned to the next section until the ore body is mined. B. A 6-8m wide ore body is temporarily left on the side near the collapsed waste rock (9) as a temporary waste rock isolation pillar (11). C. Construct a rock drilling tunnel (5) along the strike within the segment, and construct an ore extraction access road (4) in the footing. D. Construct a cutting cross passage at the end of the mining area, and construct a cutting riser at one end of the cutting cross passage; E. For ore bodies 40-50m long in the stope, drill fan-shaped medium-deep holes, using the cutting riser as the free face and compensation space, and form a cutting groove at the end of the stope. Then, use the cutting groove as the free face and supplementary space for forward mining. Each caving step is 5-6 rows, and retreat mining is carried out to the temporary waste rock isolation pillar in the stope (11). F. When the mining area is ventilated, fresh air enters the mining area through the section roadway (3), the ore exit roadway (4) or the rock drilling roadway (5). The dirty air used to clean the working face is discharged to the return air roadway from the other end of the mining area or the upper section connecting roadway, and then discharged to the surface through the ventilation shaft and the return air roadway. A 1m³ remote-controlled shovel is used to enter the goaf area or to ore exit through the ore exit roadway (4). The ore is shoveled and poured into the nearest chute to enter the transportation section and is transported to the surface. G. After the mining area is mined, a goaf is formed. For the temporary waste rock isolation pillar (11), the explosive amount is increased by using small hole mesh parameters and throwing blasting method to blast the temporary waste rock isolation pillar (11) to the other side of the goaf 12m away from the waste rock to form a 45° waste rock slope (8). When the 12m segment height is 12m, its length is 12m, which can minimize the mixing of waste rock (9) during the mining process of the temporary waste rock isolation pillar (11). H. After ventilation, a remote-controlled shovel is used to enter the goaf area (7) through the ore exit road to ore out, load the ore into the nearby chute, and transport it out to the surface through the transportation section.

2. The method according to claim 1, characterized in that: The length of the 45° waste rock slope (8) formed in step A is within 10m.

3. The method according to claim 1, characterized in that... Step C, the rock drilling tunnel (5) and the ore extraction access road (4) adopt a flat bottom structure, which facilitates the remote control of the shovel loader to enter the mining area for ore extraction.

4. The method according to claim 1, characterized in that: Step E involves drilling using a YGZ-90 drilling rig or a Simba 1354 drilling rig.

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