A stope layout method for parallel mining of steeply inclined ore bodies

Abstract

This invention discloses a stope structure layout for the parallel mining of steeply inclined ore bodies. The bottom stope (12) and the upper stope (15) are combined into a middle section with a height of 80-100m in the vertical direction of the ore body. An upward fan-shaped hole (10) is arranged in the bottom drilling roadway (9) below the bottom stope (12). After the upward fan-shaped hole (10) is blasted, a bottom ore collection trench (7) is formed. The vertical downward large hole (11) of the bottom stope is arranged in the upper middle section drilling chamber (13). The vertical downward large hole (14) of the upper stope is arranged in the top drilling chamber (16) located at the top of the upper stope (15). The retaining wall pillars (21) are left on both sides of the stope in the blasting area. This invention can merge multiple intermediate sections within a mining area, significantly reducing mine preparation work, increasing the production capacity of a single mining site, improving the ore recovery rate, reducing ore resource losses, extending the service life of the mine, lowering the cost per ton of ore, and increasing enterprise profits.

Description

Technical Field

[0001] This invention belongs to the field of underground mining technology, specifically relating to a stope structure layout for mining steeply inclined ore bodies. It can be widely applied in the mining of steeply inclined ore bodies in underground metal and non-metal underground mines, including those for metallurgy and non-ferrous metals. Background Technology

[0002] Steeply dipping, thick ore bodies represent a relatively complex orebody morphology, posing significant mining challenges. Currently, numerous mining methods exist both domestically and internationally for steeply dipping, thick ore bodies, primarily including layered backfilling, sublevel open-pit mining, and storage-based mining methods. These methods each possess certain advantages and disadvantages in terms of mining efficiency, safety, and economic costs.

[0003] The challenges of mining steeply dipping, thick ore bodies mainly include safety and efficiency issues. Safety issues manifest primarily in the irregular ore body shape and poor stope stability, which can easily lead to stope collapses and personnel casualties. Efficiency issues mainly stem from the inappropriate selection of mining methods, which can easily result in low mining efficiency and increased mining costs. However, solely emphasizing mining safety can also lead to a decline in resource recovery rates. Therefore, how to improve mining efficiency, reduce mining costs, and increase resource recovery rates while ensuring mining safety is a significant technical challenge.

[0004] With the rapid development of mining technology and mechanized mining equipment, mines originally designed with open-cut backfilling and intermediate level heights of 40-50m no longer meet the requirements of modern intelligent and efficient mining in terms of stope size, mining-cutting ratio, ore dilution, losses, and mining costs. Multi-intermediate coordinated and parallel mining is the inevitable development direction for existing large mines to achieve low-cost and efficient ore recovery.

[0005] When mining a ore body using the stope-filling method, the original stope height is limited by drilling, ore extraction equipment, and existing development works. Ore extraction structures, including receiving roadways and ore extraction access routes, need to be installed at the bottom of each intermediate section, and 5-10m high roof pillars need to be left at the top. This leads to increased drilling, transportation, and preparation work for the mining company, as well as losses of ore in the roof and bottom pillars. This is especially true for steeply dipping, thick ore bodies where high production capacity is required and multiple intermediate sections and multiple stopes are being mined simultaneously.

[0006] The article "Selection of Mining Methods for Steeply Dipping Ore Bodies," published in the February 2005 issue of *China Manganese Industry*, compared different methods and found that staged stope mining involves less engineering work, lower labor intensity for workers, easier ore transportation in the stope, higher ore recovery rates, better mining safety, higher labor productivity, lower costs, and better economic benefits. However, this mining method suffers from a high ore loss rate of 21%–30%, and is not suitable for large-scale, mechanized mining, resulting in relatively low production efficiency and a low degree of mechanization. Summary of the Invention

[0007] The purpose of this invention is to address the technical challenges of existing technologies, such as large preparatory work volume, low recovery rate, failure to meet the requirements of modern intelligent and efficient mining, and surface subsidence. It provides a mining layout method for parallel mining of steeply inclined ore bodies with less preparatory work volume and fewer mining faces, higher resource recovery rate, and higher safety, thus providing operational conditions for mechanized and intelligent operations in underground mines.

[0008] To achieve the above-mentioned objectives of the present invention, the following technical solution is adopted for the layout of a stope structure for parallel mining of steeply inclined ore bodies:

[0009] This invention discloses a stope structure layout for parallel mining of steeply inclined ore bodies. An upper mid-section drilling chamber is located between the bottom stope and the upper stope. A haulage roadway along the vein in the lower footwall of the upper mid-section connects to the right end of the upper mid-section drilling chamber, and a haulage roadway along the vein in the upper hanging wall of the upper mid-section connects to the left end of the upper mid-section drilling chamber. The bottom drilling roadway is located below the bottom stope, and a haulage roadway along the vein in the lower footwall of the lower mid-section connects to the right end of the bottom drilling roadway. The lower mid-section hanging wall... The haulage roadway along the vein is connected to the left end of the bottom drilling roadway; the ore outlet roadway is set at intervals and is connected to the bottom drilling roadway; the bottom drilling roadway and the upper middle section drilling chamber all pass through the boundary line of the ore body; a roof support pillar is provided on the top of the upper stope, and the top drilling chamber is located between the roof support pillar and the upper stope. The haulage roadway along the vein in the footwall of the drilling chamber is connected to the right end of the top drilling chamber, and the haulage roadway along the vein in the footwall of the drilling chamber is connected to the left end of the top drilling chamber. To effectively reduce the amount of preparatory work and the number of longwall faces, and to create conditions for improving the level of mechanization and intelligent operation in underground mines, this invention calculates and analyzes the stability of the goaf after segment merging based on the strength of the surrounding rock and the existing intermediate sections, ensuring the stability of the goaf; based on the calculation and analysis results, intermediate sections are merged, combining the bottom and upper stopes of two intermediate sections in the same area into one intermediate section in the vertical direction of the ore body, with the height of the stope after merging being 80-100m; below the bottom stope... Upward fan-shaped holes are arranged in the bottom drilling roadway of the stope. After blasting, the upward fan-shaped holes form the bottom ore collection trench. Vertical downward large holes are arranged in the upper middle section drilling chamber above the bottom stope as the main blasting holes of the bottom stope. Vertical downward large holes are arranged in the top drilling chamber located at the top of the upper stope as the main blasting holes of the upper stope. In order to ensure the stability of the stope and avoid the production blasting from affecting the safety of adjacent stops, retaining pillars are left on both sides of the stope in the blasting area.

[0010] Furthermore, it is preferable that the upper middle section drilling chambers are arranged in parallel. To ensure the stability of the drilling chambers, a spacer is left between adjacent upper middle section drilling chambers, with the thickness of the spacer preferably ranging from 2.2 to 4.5 m; similarly, it is preferable that the top drilling chambers are also arranged in parallel, with a spacer left between adjacent top drilling chambers, with the thickness of the spacer preferably ranging from 2.2 to 4.5 m.

[0011] Furthermore, the depth of the upward fan-shaped hole is generally in the range of 15 to 20 m, the depth of the vertical downward large hole of the bottom stope is generally 30 to 40 m, and the depth of the vertical downward large hole of the upper stope is generally 30 to 48 m.

[0012] Furthermore, the thickness of the retaining pillar is generally 1.6 to 3.5 m, mostly 1.8 to 2.5 m.

[0013] For steeply dipping, thick ore bodies, the typical stope structure parameters for parallel mining are: pillar thickness of 2.5–3.0 m, depth of upward fan-shaped boreholes of 16–18 m, depth of vertical downward large boreholes in the bottom stope of 32–38 m, depth of vertical downward large boreholes in the upper stope of 38–45 m, and wall pillar thickness of 1.8–2.5 m.

[0014] In this invention, during ore mining, the bottom stope is blasted first, with only 10% to 20% of its volume extracted to leave room for compensation in the top stope. After the bottom stope is completely blasted, the ore in the upper stope is then blasted. During the blasting of the upper stope, the ore volume extracted each time is 10% to 20% of the blasted area. This provides compensation space for subsequent vertical downward large-hole blasting of the upper stope and also allows the loose ore to support the surrounding rock, thereby reducing... The exposed area of ​​the stope during the mining process was measured; after all the ore collapsed, the bottom ore collection trench and the ore extraction roadway of the bottom stope were used to concentrate and strengthen the ore extraction in the two stops after the section was merged using trackless equipment in the ore extraction roadway; the remaining ore body in the bottom ore collection trench was extracted using a remote-controlled loader. All the ore was extracted within 1 to 2 months. After the ore was extracted, the stope was immediately closed and the closed stope was filled to form a backfill body, so as to achieve strong mining and filling in the stopes after the section was merged and reduce the exposure time of the goaf.

[0015] The stope structure layout method for parallel mining of steeply dipping ore bodies, as described in this invention, achieves efficient multi-section parallel mining of thick, steeply dipping ore bodies with significant economic benefits. Specifically, it exhibits the following positive effects:

[0016] (1) The present invention can merge multiple intermediate sections in the mining area, which can significantly reduce the mining preparation work, increase the production capacity of a single mining site, increase the recovery rate of ore, reduce the loss of ore resources, extend the service life of the mine, reduce the cost per ton of ore, and increase the benefits of the enterprise.

[0017] (2) After the method of the present invention is used for segmented mining, the number of pillars for the roof support of the bottom stope in the lower middle section and the pillars for the ore collection trench in the upper stope is reduced, and the resources of the pillars for the roof support of the bottom stope in the lower middle section and the pillars for the ore collection trench in the upper stope are recovered, which greatly improves the resource recovery rate.

[0018] (3) After the method of the present invention is used for segmented mining, the mining preparation works such as bottom ore-exit roadway and ore-gathering trench in the upper and middle sections of the upper ore chamber are reduced, the ore recovery efficiency is improved, and the production cost of the mine is greatly reduced.

[0019] (4) In addition, the method of the present invention can effectively reduce the number of mining areas, reduce dangerous working faces, and improve the inherent safety of mines.

[0020] (5) Experimental research statistics show that after the method of the present invention is used for segmented mining, it can reduce the preparation work by 35% to 40%, increase the resource recovery rate by 12% to 15%, reduce the number of mining sites by about one-third, and extend the service life of the mine by 1 to 2 years. Attached Figure Description

[0021] Figure 1 This invention provides a diagram of the preparatory work and blast hole layout for a mining operation in a sectioned mining of a steeply inclined ore body, which is perpendicular to the strike of the ore body within the mining area.

[0022] Figure 2 This invention provides a layout diagram of the mining preparation engineering at the bottom of the ore body perpendicular to the strike of the ore body in a mining area for a stope structure arrangement method of parallel mining of steeply inclined ore bodies.

[0023] Figure 3 This invention provides a plan view of the layout of drilling chambers vertical to the ore body in a mining area for a method of mining a steeply inclined ore body in parallel sections.

[0024] The attached diagram is labeled as follows: 1-Lower middle section footwall haulage roadway; 2-Lower middle section hanging wall haulage roadway; 3-Upper middle section footwall haulage roadway; 4-Upper middle section hanging wall haulage roadway; 5-Drilling chamber footwall haulage roadway; 6-Drilling chamber hanging wall haulage roadway; 7-Bottom-collecting ore trench; 8-Exit haulage roadway; 9-Bottom drilling roadway; 10-Upward fan-shaped hole; 11-Bottom stope vertical downward large hole; 12-Bottom stope; 13-Upper middle section drilling chamber; 14-Upper stope vertical downward large hole; 15-Upper stope; 16-Top drilling chamber; 17-Roof pillar; 18-Ore body boundary line; 19-Infill body; 20-Interstitial pillar; 21-Wall pillar. Detailed Implementation

[0025] To better describe the present invention, the following description, in conjunction with the accompanying drawings and embodiments, provides a more detailed description of a stope structure layout for parallel mining of steeply inclined ore bodies.

[0026] Depend on Figure 1 The diagram shown illustrates the layout of a stope structure for parallel mining of a steeply inclined ore body according to the present invention, including the layout of the bottom preparatory engineering structure perpendicular to the strike of the ore body within the mining area. Figure 2 , Figure 3 As can be seen, in an embodiment of efficient inter-section mining of an iron ore mine, an upper middle section drilling chamber 13 is provided between the bottom stope 12 and the upper stope 15. The upper middle section drilling chambers 13 are arranged in parallel, and a spacer 20 with a thickness of 2.8m is left between adjacent upper middle section drilling chambers 13. The upper middle section footwall haulage roadway 3 is connected to the right end of the upper middle section drilling chamber 13, and the upper middle section footwall haulage roadway 4 is connected to the left end of the upper middle section drilling chamber 13. The bottom drilling roadway 9 is located below the bottom stope 12, and the lower middle section footwall haulage roadway 1 is connected to the right end of the bottom drilling roadway 9. The upper hanging wall haulage roadway 2 is connected to the left end of the bottom drilling roadway 9; the ore extraction connecting roadway 8 is spaced out and connected to the bottom drilling roadway 9; a roof support pillar 17 is provided on the top of the upper stope 15, and parallel top drilling chambers 16 are located between the roof support pillar 17 and the upper stope 15, with a spacer 20 between adjacent top drilling chambers 16, the spacer 20 being 2.8m thick; the lower hanging wall haulage roadway 5 is connected to the right end of the top drilling chamber 16, and the upper hanging wall haulage roadway 6 is connected to the left end of the top drilling chamber 16; the bottom drilling roadway 9 and the upper middle section drilling chamber 13 both pass through the ore body boundary line 18. The following steps are adopted for implementation:

[0027] 1) Based on the strength of the surrounding rock and the formed intermediate section, the stability of the goaf after the section is merged is calculated and analyzed to ensure the stability of the goaf. According to the calculation and analysis results, the bottom stope 12 and the upper stope 15 of the two intermediate sections in the same area in the vertical direction of the ore body are merged into sections. The height of the stope after merging is 92m.

[0028] 2) An upward fan-shaped hole 10 is arranged in the bottom drilling tunnel 9 at the bottom of the bottom stope 12. The depth of the upward fan-shaped hole 10 is 17m. After the upward fan-shaped hole 10 is blasted, a bottom ore collection trench 7 is formed. In the upper part of the bottom stope 12, the upper middle section drilling chamber 13 is used to arrange the bottom stope vertical downward large hole 11. The depth of the bottom stope vertical downward large hole 11 is 35m. The bottom stope vertical downward large hole 11 serves as the main blasting hole of the bottom stope 12.

[0029] 3) A large vertical hole 14 is installed in the top drilling chamber 16 located at the top of the upper stope 15 as the main blasting hole of the upper stope 15; the depth of the large vertical hole 14 is 42m.

[0030] 4) Protective pillars 21 are left on both sides of the blasting area, with a thickness of 2.1m. During ore mining, the bottom stope 12 is blasted first, and only 12% to 18% of the volume of ore in the bottom stope 12 is extracted to leave compensation space for the top stope 15. After the bottom stope 12 is completely blasted, the ore in the upper stope 15 is blasted. During the blasting of the ore in the upper stope 15, the amount of ore extracted each time is 12% to 18% of the volume of the blasting area.

[0031] 5) After all the ore has collapsed, the bottom ore collection trench 7 and the ore extraction connecting roadway 8 of the bottom stope 12 are used to concentrate and strengthen the ore extraction in the two stops after the section is merged using trackless equipment in the ore extraction connecting roadway 8; the remaining ore body in the bottom ore collection trench 7 is extracted using a remote-controlled loader. All the ore is extracted within 2 months. After the ore is extracted, the stope is immediately closed and the closed stope is filled to form the filling body 19, so as to achieve strong mining and filling of the stopes after the section is merged and reduce the exposure time of the goaf.

[0032] This invention can merge multiple intermediate sections within a mining area, significantly reducing mine preparation work, increasing the productivity of a single stope, improving ore recovery rate, reducing ore resource loss, extending the service life of the mine, reducing the cost per ton of ore, and increasing enterprise profits. In addition, this invention can effectively reduce the number of stops in a mine, reduce dangerous working faces, and improve the inherent safety of the mine.

[0033] This invention, a stope layout method for parallel mining of steeply inclined ore bodies, has been successfully applied to the efficient parallel mining of an iron ore mine. Statistics show that using this invention reduces preparatory work by 38%, increases resource recovery rate by 13%, reduces the number of mine stops by 32%, generates economic benefits of over 50 million yuan per year, extends the mine's service life by 1-2 years, achieves efficient mining after parallel mining of multiple ore bodies, and significantly reduces mine production costs.

[0034] It should be noted that the terms "upper", "lower", "left", "right", "inner", "outer", "front", "rear", "top / bottom", etc., used in this invention to indicate the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention and simplifying the description, and therefore should not be construed as limiting this invention.

[0035] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A stope layout for parallel mining of a steeply inclined ore body, wherein an upper middle section drilling chamber (13) is provided between the bottom stope (12) and the upper stope (15), the upper middle section footwall haulage roadway (3) is connected to the right end of the upper middle section drilling chamber (13), and the upper middle section footwall haulage roadway (4) is connected to the left end of the upper middle section drilling chamber (13); the bottom drilling roadway (9) is located below the bottom stope (12), the lower middle section footwall haulage roadway (1) is connected to the right end of the bottom drilling roadway (9), and the lower middle section footwall haulage roadway (2) is connected to the bottom drilling roadway (9). The left end of the tunnel (9) is connected; the ore-exit connecting tunnel (8) is set at intervals and is connected to the bottom drilling tunnel (9); the bottom drilling tunnel (9) and the upper middle section drilling chamber (13) both pass through the ore body boundary line (18); a roof support pillar (17) is provided on the top of the upper stope (15), the top drilling chamber (16) is located between the roof support pillar (17) and the upper stope (15), the lower footwall of the drilling chamber along the vein transport tunnel (5) is connected to the right end of the top drilling chamber (16), and the upper footwall along the vein transport tunnel (6) is connected to the left end of the top drilling chamber (16); the characteristic is that: In the vertical direction of the ore body, the bottom stope (12) and the upper stope (15) of the two middle sections in the same area are merged into one middle section, and the height of the stope after merging is 80-100m; an upward fan-shaped hole (10) is arranged in the bottom drilling roadway (9) under the bottom stope (12), and the upward fan-shaped hole (10) forms a bottom ore collection trench (7) after blasting. The bottom stope (12) is arranged with the upper middle section drilling chamber (13) in the upper part of the bottom stope (12) as the main blasting hole of the bottom stope (12); the upper stope (14) is arranged with the upper stope (15) as the main blasting hole of the upper stope (15) in the top drilling chamber (16) located at the top of the upper stope (15); the wall pillars (21) are left on both sides of the stope in the blasting area.

2. The stope structure layout method for parallel mining of steeply inclined ore bodies as described in claim 1, characterized in that: The height of the mining area after the section is 86-94m.

3. The stope structure layout for parallel mining of steeply inclined ore bodies as described in claim 1, characterized in that: The upper middle section rock drilling chambers (13) are arranged in parallel, and a column (20) is left between adjacent upper middle section rock drilling chambers (13). The thickness of the column (20) is 2.2 to 4.5 m. The top rock drilling chambers (16) are arranged in parallel, and a column (20) is left between adjacent top rock drilling chambers (16). The thickness of the column (20) is 2.2 to 4.5 m.

4. The stope structure layout for parallel mining of steeply inclined ore bodies as described in claim 1, characterized in that: The depth of the upward fan-shaped hole (10) is in the range of 15 to 20 m, and the depth of the bottom stope vertical downward large hole (11) is 30 to 40 m.

5. A stope layout for parallel mining of steeply inclined ore bodies as described in claim 1, 2, 3, or 3, characterized in that: The depth of the vertical downward large hole (14) in the upper stope is 30-48m.

6. The stope structure layout for parallel mining of steeply inclined ore bodies as described in claim 5, characterized in that: The thickness of the wall support pillar (21) is 1.6 to 3.5 m.

7. The stope structure layout for parallel mining of steeply inclined ore bodies as described in claim 6, characterized in that: The thickness of the retaining pillar (21) is 1.8 to 2.5 m.

8. The stope structure layout for parallel mining of steeply inclined ore bodies as described in claim 3, characterized in that: The thickness of the interstitial pillar (20) is 2.2 to 4.5 m; the depth of the upward fan-shaped hole (10) is in the range of 16 to 20 m; the depth of the bottom stope vertical downward large hole (11) is 32 to 39 m; the depth of the upper stope vertical downward large hole (14) is 32 to 45 m; the thickness of the retaining pillar (21) is 1.8 to 3.0 m; the thickness of the retaining pillar (21) is 1.8 to 2.5 m.

9. The stope structure layout for parallel mining of steeply inclined ore bodies as described in claim 8, characterized in that: The thickness of the interstitial pillar (20) is 2.5 to 3.0 m, the depth of the upward fan-shaped hole (10) is in the range of 16 to 18 m, the depth of the bottom stope vertical downward large hole (11) is 32 to 38 m, the depth of the upper stope vertical downward large hole (14) is 38 to 45 m; the thickness of the retaining pillar (21) is 1.8 to 2.5 m.

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