Medium-length hole backfilling recovery process between benches in gently inclined medium-thick ore body

Abstract

This application discloses a deep-hole backfilling and recovery process for inter-pillars in gently dipping, medium-thick ore bodies, belonging to the field of mining engineering technology. The process includes: S2, scraping the sides of the original stope ventilation and pedestrian shaft to convert it into a drilling tunnel. The ventilation and pedestrian shaft is set parallel to the ore body dip and located directly below the inter-pillar; S3, constructing an electric scraper track in the lower part of the drilling tunnel within the inter-pillar, from the horizontal plane of this section to the horizontal plane of the next section. The electric scraper track is parallel to and runs in the same direction as the drilling tunnel; S4, constructing a bucket tunnel laterally from the electric scraper track, and constructing a bucket neck upwards from the bucket tunnel to connect with the drilling tunnel. The construction progress of the bucket tunnel and the bucket neck is consistent with that of the electric scraper track. Through the spatial coordination of S2 (converting the drilling tunnel), S3 (constructing the electric scraper track), and S4 (constructing the bucket tunnel and bucket neck), the pain points of gently dipping ore bodies being unable to self-flow and unable to be equipped with trackless equipment are solved.

Description

Technical Field

[0001] This invention belongs to the field of mining engineering technology, and in particular relates to a process for subsequent backfilling and recovery of deep holes in inter-mining pillars of gently dipping medium-thick ore bodies. Background Technology

[0002] In existing open-cut ore mining processes, pillars are often left between stopes to support the roof and overlying strata, maintaining stope stability. However, pillar recovery becomes a challenge after stope extraction, leading to reduced ore recovery rates and increased losses. Pillars in gently dipping, medium-thick ore bodies are often 8-12m long, and their mining conditions are complex, making gravity flow of ore difficult and hindering ore transport. Furthermore, excessively steep ore body slopes restrict the operation of trackless mining equipment, easily resulting in reduced ore extraction efficiency. Summary of the Invention

[0003] In view of the technical problems existing in the background art, this application provides a process for subsequent backfilling and recovery of deep holes in inter-mining pillars of gently dipping medium-thick ore bodies, including: S1. Select the pillar between two mined and filled ore chambers as the mining pillar; S2. The original ventilation and pedestrian shaft of the mine is brushed and transformed into a rock drilling tunnel. The ventilation and pedestrian shaft is set parallel to the dip of the ore body and located directly below the intercolumn. S3. In the lower part of the rock drilling tunnel in the column, construct an electric scraper track from the horizontal plane of this middle section to the horizontal plane of the next middle section. The electric scraper track is parallel to the rock drilling tunnel and has the same direction. S4. Construct the bucket tunnel laterally from the electric scraper track, and construct the bucket neck upward from the bucket tunnel to connect with the rock drilling tunnel, and the construction progress of the bucket tunnel and the bucket neck should be consistent with that of the electric scraper track. S5. A ore pass and an electric scraper winch chamber shall be installed near the horizontal level of this middle section of the electric scraper track; S6. Before mining, drill horizontal holes laterally in the rock drilling tunnel, and blast to form a cutting tunnel. The boundary of the cutting tunnel is consistent with the thickness of the pillar, forming a bottom-pulling space. S7. After leaving a bottom pillar at the bottom of the cutting tunnel, construct the cutting shaft vertically upwards, with the boundary of the cutting shaft extending beyond the ore body. S8. Construct upward fan-shaped holes in the upper pillar ore body within the rock drilling tunnel, using the cut-up well as the free face, the cut-up cross tunnel as the compensation space, and the funnel as the ore falling structure for medium-deep hole blasting. S9. Ventilate the working face. The airflow enters the electric scraper roadway from the lower middle section, enters the mining area through the bucket neck, and after scouring, is discharged into the upper middle section through the electric scraper roadway and the upper section of the rock drilling roadway. S10. After blasting, the ore enters the electric scraper channel through the funnel, and is then removed and transported out using an electric scraper. S11. After the ore in the mining area is cleared, install the filling pipe and dewatering pipe; S12. Construct the electric scraper road, rock drilling tunnel, pedestrian connecting road, and chute filling retaining wall that connects with the lower middle section, and then fill the empty area in sections.

[0004] In some implementations, in step S5, if the electric scraper path intersects with the existing cross-cutting vein, a platform is directly set at the intersection to allow ore to be released.

[0005] In some embodiments, in step S5, if the electric scraper path is too long, a chute and a winch chamber are added in the middle of the electric scraper path to divide the intercolumn into two or three sections for mining, and at the same time, the cross-section is extended to connect with the chute.

[0006] In some embodiments, after step S6, the process further includes: S61. Expand the upper part of the bucket neck downwards from the bottom space to form a funnel mouth.

[0007] In some embodiments, after step S61, the process further includes: S62. The waste rock produced by blasting is piled up at the funnel opening and leveled to be used as a working platform for mining and drilling.

[0008] In some implementations, in step S8, the blasting sequence for medium-deep holes is from bottom to top.

[0009] In some implementations, in step S8, the medium-deep hole blasting employs sequential, row-by-row, segmented, micro-delay blasting.

[0010] In some implementations, in step S10, if the surrounding rock of the mining area has poor stability, only a portion of the ore is extracted after each blast, and the remaining ore is temporarily left in the empty area until all blasting is completed and the ore is extracted in a concentrated manner.

[0011] In some implementations, in step S11, the empty area is divided into two parts, and two filling pipes are provided with their outlets separately arranged at the center of the two parts of the empty area.

[0012] In some embodiments, in step S12, the subsequent filling of the hollow area bottom plate to the predetermined height of the filling retaining wall is carried out using low-ash sand ratio cemented filling, and the interval from the predetermined height to the top height is filled with tailings.

[0013] This invention provides a process for subsequent backfilling and recovery of deep holes in inter-mining pillars of gently dipping, medium-thick ore bodies, comprising: S1. Select the pillar between two mined and filled ore chambers as the mining pillar; S2. The original ventilation and pedestrian shaft of the mine is brushed and transformed into a rock drilling tunnel. The ventilation and pedestrian shaft is set parallel to the dip of the ore body and located directly below the intercolumn. S3. In the lower part of the rock drilling tunnel in the column, construct an electric scraper track from the horizontal plane of this middle section to the horizontal plane of the next middle section. The electric scraper track is parallel to the rock drilling tunnel and has the same direction. S4. Construct the bucket tunnel laterally from the electric scraper track, and construct the bucket neck upward from the bucket tunnel to connect with the rock drilling tunnel, and the construction progress of the bucket tunnel and the bucket neck should be consistent with that of the electric scraper track. S5. A ore pass and an electric scraper winch chamber shall be installed near the horizontal level of this middle section of the electric scraper track; S6. Before mining, drill horizontal holes laterally in the rock drilling tunnel, and blast to form a cutting tunnel. The boundary of the cutting tunnel is consistent with the thickness of the pillar, forming a bottom-pulling space. S7. After leaving a bottom pillar at the bottom of the cutting tunnel, construct the cutting shaft vertically upwards, with the boundary of the cutting shaft extending beyond the ore body. S8. Construct upward fan-shaped holes in the upper pillar ore body within the rock drilling tunnel, using the cut-up well as the free face, the cut-up cross tunnel as the compensation space, and the funnel as the ore falling structure for medium-deep hole blasting. S9. Ventilate the working face. The airflow enters the electric scraper roadway from the lower middle section, enters the mining area through the bucket neck, and after scouring, is discharged into the upper middle section through the electric scraper roadway and the upper section of the rock drilling roadway. S10. After blasting, the ore enters the electric scraper channel through the funnel, and is then removed and transported out using an electric scraper. S11. After the ore in the mining area is cleared, install the filling pipe and dewatering pipe; S12. Construct the electric scraper road, rock drilling tunnel, pedestrian connecting road, and chute filling retaining wall that connects with the lower middle section, and then fill the empty area in sections.

[0014] By transforming the original ventilation and pedestrian well in S2 into a rock drilling tunnel, the problems of high cost, long construction period, and insufficient space in the original well affecting rock drilling efficiency caused by the need to excavate new rock drilling tunnels were solved. This allows the well to serve two purposes, which helps to reduce the amount of tunnel excavation, lower costs, and take into account both construction convenience and safety.

[0015] By constructing an electric scraper roadway parallel to and aligned with the drilling roadway in the lower part of the drilling roadway within the S3 column, from the horizontal plane of this middle section to the horizontal plane of the next middle section, the problem of ore not being able to flow by itself in gently dipping ore bodies and the lack of a dedicated ore discharge channel was solved. This, in turn, built a stable foundation for electric scraper operations and shortened the subsequent ore transport path, which is conducive to improving ore transfer efficiency.

[0016] By constructing the bucket tunnel laterally from the electric scraper track in S4 and connecting the bucket neck upward from the bucket tunnel with the rock drilling tunnel, the problems of the fault between the rock drilling tunnel and the electric scraper track and the long distance of ore transportation are solved, thus forming a complete channel for ore transfer, which is conducive to improving ore extraction efficiency.

[0017] By utilizing the spatial collaboration of S2 (modified rock drilling tunnel), S3 (construction electric scraper roadway), and S4 (construction bucket tunnel and bucket neck), the pain point of the gently inclined ore body being unable to flow by itself and unable to be equipped with trackless equipment was solved.

[0018] Through the collaboration of S2, S3, S4 and S9, the problems of additional excavation of return airway for mining ventilation, high cost and easy damage to surrounding rock, and uneven air intake leading to insufficient local ventilation were solved. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of this application, the accompanying drawings used in this application will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without any creative effort.

[0020] Figure 1 This is a schematic diagram of the overall process engineering layout for a deep-hole filling and recovery process for a gently dipping, medium-thick ore body in a stope, provided in the embodiments of this application. Figure 2 This is a schematic diagram showing the positional relationship between the bucket crossbar, bucket neck, and electric scraper track in a deep hole filling and recovery process of a gently dipping medium-thick ore body in a stope, as provided in the embodiments of this application. Figure 3 This is a schematic diagram showing the positional relationship between the open space formed after blasting of the ore body and the electric scraper track in a deep hole filling and recovery process of a gently dipping medium-thick ore body in a stope, as provided in the embodiments of this application. Figure 4 This is a schematic diagram of a medium-deep hole blasting process for a gently dipping, medium-thick ore body in a stope column with subsequent backfilling and recovery, as provided in the embodiments of this application.

[0021] Explanation of reference numerals in the attached diagram: 1. Lower haulage roadway; 2. Upper haulage roadway; 3. Through vein; 4. Filling body; 5. Ore body; 6. Drilling roadway; 7. Electric scraper roadway; 8. Bucket pass; 9. Bucket neck; 10. Platform leak; 11. Passage; 12. Cutting roadway; 13. Cutting shaft; 14. Drill hole; 15. Electric scraper; 16. Bottom space. Detailed Implementation

[0022] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0024] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0025] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0026] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0027] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0028] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0029] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0030] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0031] For ease of understanding, an exemplary working condition is provided for reference. Figure 1 The hanging wall of ore body 5 has a hanging wall haulage roadway 2, which can serve as an auxiliary channel for return air in the stope or as equipment required for temporary transfer of pillar mining. The footwall of ore body 5 has a footwall haulage roadway 1, whose core function is to receive ore transferred from the ore pass 11 or platform sluice 10 and transport the ore to the intermediate crushing station via underground locomotives. It is the main transportation route for ore from the stope to the surface. The footwall haulage roadway 1 and the hanging wall haulage roadway 2 are directly connected by a cross-vein 3, which is a transverse roadway perpendicular to the strike of ore body 5 and is used to connect the cross-vein roadway and the haulage roadway.

[0032] In some implementations, refer to Figure 1 A process for subsequent backfilling and recovery of deep boreholes in the inter-stope pillars of a gently dipping, medium-thick ore body, comprising: S1. Select a pillar between two mined and backfilled stops as the mining pillar. Specifically, the backfilled stops can form a supporting structure on both sides of the pillar, reducing the risk of roof collapse and spalling during mining. At the same time, it can clearly define the mining boundary, avoid confusion with unmined stops, and reduce resource waste. For example, select ore body 5 in the 40-50 meter section of a certain mine as the mining target. This ore body 5 is located between two stops that have been fully cemented and backfilled with tailings 4. It is 15 meters thick, 7 meters wide, dips at 25°, and has a length of about 140 meters. Drilling is conducted in advance to confirm that there are no geological defects such as faults or karst caves in the pillar.

[0033] S2. The original ventilation and pedestrian shaft in the stope is resurfaced and converted into a drilling tunnel 6. The ventilation and pedestrian shaft is set parallel to the dip of the ore body 5 and located directly below the pillar. Specifically, during the preparation stage of stope mining, the ventilation and pedestrian shaft is set parallel to the dip of the ore body 5 and is excavated directly below the pillar, unlike the traditional vertical setting of ventilation shafts. This allows the existing ventilation and pedestrian shaft to be reused during subsequent pillar mining without the need to excavate a new drilling tunnel 6, reducing the amount of tunnel excavation and costs. After resurfacing, the dimensions are adapted to the drilling equipment, avoiding low drilling efficiency due to insufficient space, providing a working space that meets specifications for subsequent medium and deep hole drilling, while retaining the original shaft's ventilation function, thus balancing construction convenience and safety. For example, the original ventilation pedestrian well cross-section was 2.0×2.0 meters. A YT-28 rock drill with a gold drill bit was used to perform side-scraping operations to expand the cross-section to 2.8×2.8 meters to match the minimum working space requirements of the subsequent TJ25 rock drilling platform. During the side-scraping process, anchor bolts and metal mesh were used for support every 1 meter of excavation to ensure the stability of the tunnel wall.

[0034] S3. In the lower part of the drilling tunnel 6 within the inter-column, construct the electric scraper track 7 from the horizontal plane of this intermediate section to the horizontal plane of the next intermediate section. The electric scraper track 7 is parallel to the drilling tunnel 6 and runs in the same direction. Specifically, the electric scraper track 7 is arranged parallel to the drilling tunnel 6. The electric scraper track 7 is set in the surrounding rock of the bottom plate, with strong bearing capacity, suitable for long-term operation of electric scraper equipment, thereby constructing a dedicated ore extraction channel to solve the problem that the ore in the gently inclined ore body 5 cannot flow by itself, and to provide a foundation for subsequent electric scraper ore extraction. The electric scraper track 7 is arranged directly below or diagonally below the drilling tunnel 6 and kept parallel, so that in subsequent work, the same length bucket 8 (from S4) can be constructed to directly fall into the electric scraper track 7 below, shortening the ore transportation path and improving the ore transfer efficiency. For example, the electric scraper roadway 7 is constructed from the horizontal plane of this middle section to the horizontal plane of the next middle section. It is excavated using an EBZ-120 type tunneling machine with a specification of 2.2×2.2 meters. During the construction process, the direction is controlled by a laser pointer to ensure parallelism with the rock drilling tunnel 6. Shotcrete support is used every 5 meters of excavation to prevent weathering and spalling of the surrounding rock.

[0035] S4. Construct bucket tunnel 8 laterally from electric scraper chute 7, and construct bucket neck 9 upward from bucket tunnel 8 to connect with rock drilling tunnel 6. The construction progress of bucket tunnel 8 and bucket neck 9 should be consistent with that of electric scraper chute 7. Specifically, bucket tunnel 8 and bucket neck 9 form a vertical channel connecting rock drilling tunnel 6 (blasting ore dumping area) and electric scraper chute 7 (ore extraction area). This ensures that the blasted ore can directly enter electric scraper chute 7 through the path of bucket neck 9 and bucket tunnel 8, reducing the ore transportation distance and thus constructing a complete ore dumping and extraction connection channel to improve ore extraction efficiency. For example, a pneumatic pick is used to construct the bucket tunnel 8, which has a size of 2.0×2.0 meters and a length of 0.5 meters, penetrating the side wall of the electric scraper roadway 7 to the pillar ore body 5; then, the bucket neck 9 is constructed from the bottom of the bucket tunnel 8 upwards, with the same cross-sectional dimensions as the bucket tunnel 8, using a handheld rock drill for drilling and blasting, and the slag is cleared every 0.5 meters of excavation; before each day's construction, the progress of the electric scraper roadway 7, bucket tunnel 8, and bucket neck 9 is checked to ensure that the bucket neck 9 can connect to the bottom of the drilling tunnel 6.

[0036] S5. Set up a ore chute and an electric scraper winch chamber near the middle level of the electric scraper track 7 to improve the ore extraction system, solve the problem of centralized transfer of ore in the electric scraper track 7, and improve the overall ore extraction efficiency.

[0037] S6. Before mining, drill horizontal holes laterally in the rock drilling roadway 6 and blast to form a cutting roadway 12. The boundary of the cutting roadway 12 is consistent with the thickness of the pillar, forming a bottom-pulling space 16, which provides compensation space for subsequent medium-deep hole blasting and avoids insufficient ore crushing due to insufficient blasting energy. The boundary is consistent with the thickness of the pillar to ensure accurate mining range, without wasting resources or damaging the surrounding backfill 4.

[0038] S7. After leaving a bottom pillar at the bottom of the cutting tunnel 12, construct the cutting shaft 13 vertically upwards. The boundary of the cutting shaft 13 extends beyond the ore body 5. The bottom pillar can support the weight of the surrounding rock during the construction of the cutting shaft 13 and prevent the cutting shaft 13 from collapsing. The boundary of the cutting shaft 13 extends 2m beyond the ore body to ensure that the boundary of the ore body 5 can be completely covered during blasting, with no residual ore, further expanding the free face and providing more sufficient energy release space for upward fan-shaped hole blasting.

[0039] S8. In the rock drilling tunnel 6, construct upward fan-shaped holes in the upper pillar ore body 5. Use the cutting riser as the free surface, the cutting cross tunnel as the compensation space, and the funnel as the ore dropping structure for medium-deep hole blasting. The upward fan-shaped holes have a wide coverage area, which can reduce the number of rock drilling operations. The row-by-row micro-differential blasting can reduce the disturbance to the surrounding rock and avoid damage to the filling body 4. The funnel ore dropping structure ensures that the ore can be concentrated into the neck 9, reducing the amount of loose ore.

[0040] S9. Ventilate the working face. The airflow enters the electric scraper roadway 7 from the lower middle section, passes through the bucket neck 9 of the bucket tunnel 8, and enters the stope. After flushing, the airflow is discharged into the upper middle section through the electric scraper roadway 7 and the upper section of the rock drilling roadway 6. The airflow path covers the entire stope with no ventilation dead spots. Combined with the auxiliary ventilation of the local fan, harmful gases after blasting can be quickly removed, reducing the risk of poisoning to workers, creating a safe working environment, and ensuring that the ore extraction operation can be carried out in the stope in a timely manner after blasting without delaying the construction period.

[0041] S10. After blasting, the ore enters the electric scraper channel 7 through the funnel, and is then removed and transported out by electric scraper. The blasted ore is then transferred to the ore pass to complete the ore recovery.

[0042] S11. After the ore in the mining area is cleared, the filling pipe and dewatering pipe are installed to prepare for subsequent filling and provide stable support for the next round of mining.

[0043] S12. Construct filling retaining walls for the electric scraper roadway 7, rock drilling roadway 6, pedestrian connecting roadway and chute 11, etc., which are connected to the lower middle section. Then, fill the goaf area in sections to seal the goaf area. The filling body 4 supports the surrounding rock, eliminates the hidden dangers of the goaf area, and provides a safe boundary for the mining of adjacent pillars.

[0044] The collaborative relationship between S2, S3, and S4 is as follows: The location design of S2 (modified drilling tunnel 6), S3 (construction of electric scraper chute 7), and S4 (construction of bucket tunnel 8 and bucket neck 9) spatially defines the shortest path for ore transfer, including the ore drop zone, connection zone, and transfer zone. The modified drilling tunnel 6 in S2 is set parallel to the dip of the ore body 5 and located directly below the pillar. The electric scraper chute 7 constructed in S3 is parallel to the drilling tunnel 6 and runs in the same direction. This means that the two always have a controllable distance in space, and the length of this distance is the distance that the blasted ore travels vertically into the electric scraper chute 7, minimizing the transfer distance and also providing conditions for the subsequent construction of bucket tunnel 8 and bucket neck 9 in S4. In the S4 construction of bucket tunnel 8 and bucket neck 9, bucket tunnel 8 is constructed laterally from electric scraper 7, that is, horizontally penetrating the side wall of electric scraper 7. Bucket neck 9 is constructed upward from bucket tunnel 8 and connects with rock drilling tunnel 6, that is, vertically connecting to the ore drop area, forming an L-shaped connecting channel with rock drilling tunnel 6 for ore drop, bucket neck 9 for vertical flow guidance, bucket tunnel 8 for horizontal transition, and electric scraper 7 for transfer. This solves the pain point that the ore in the gently inclined ore body 5 cannot flow by itself and cannot be equipped with trackless equipment: after the medium-deep hole blasting, the ore falls naturally into bucket neck 9 under the action of gravity, and smoothly enters electric scraper 7 through bucket tunnel 8, which is adapted to the gravity guidance characteristics of the gently inclined ore body 5 and avoids the transfer interruption point.

[0045] The collaborative relationship between S2, S3, S4, and S9 is as follows: S2, S3, and S4 provide the necessary pathways for the overall ventilation process of S9. The ventilation walkway modified by S2 is positioned parallel to the dip of the ore body 5 and directly below the inter-pillar, with its direction along the vein consistent with the length of the inter-pillar. This layout allows the modified drilling roadway 6 to extend along the full length of the inter-pillar, perfectly covering the return air requirement of the airflow from the stope into the upper and middle sections of S9. If this walkway were not reused, an additional return airway parallel to the inter-pillar would need to be excavated, increasing both the construction period and cost, and potentially damaging the stability of the surrounding rock. S2 achieves dual use of the roadway, providing a ready-made return air path for S9. S3 requires the electric scraper track 7 to be parallel to and aligned with the drilling roadway 6, extending along the length of the inter-pillar. This alignment ensures that fresh air is evenly distributed along the entire length of the electric scraper track 7, and then dispersed to various areas of the stope through the bucket neck 9 of S4, avoiding dead zones with insufficient local ventilation. For example, with a column length of 140m (exemplary data), after the electric scraper track 7 is arranged along its entire length, the fresh air energy in the lower and middle sections can be evenly introduced from the starting point to the end point of the electric scraper track 7. Each bucket neck 9 can be allocated sufficient air volume, ensuring that there is a supply of fresh air no matter where the mining area is mined. This is something that cannot be achieved with a non-parallel layout.

[0046] This application provides a process for subsequent backfilling and recovery of deep holes in the inter-stop pillar of a gently dipping, medium-thick ore body, including: S1. Select the pillar between two mined and filled ore chambers as the mining pillar; S2. The original ventilation and pedestrian shaft of the mine is brushed and transformed into a rock drilling tunnel 6. The ventilation and pedestrian shaft is set parallel to the ore body 5 and located directly below the pillar. S3. In the lower part of the rock drilling tunnel 6 in the inter-column, construct the electric scraper roadway 7 from the horizontal plane of this middle section to the horizontal plane of the next middle section. The electric scraper roadway 7 is parallel to the rock drilling tunnel 6 and has the same direction. S4. Construct bucket tunnel 8 laterally from electric scraper track 7, and construct bucket neck 9 upward from bucket tunnel 8 to connect with rock drilling tunnel 6, and the construction progress of bucket tunnel 8 and bucket neck 9 is consistent with that of electric scraper track 7. S5. A ore pass and an electric scraper winch chamber shall be installed at the horizontal position of the electric scraper track 7 near the middle section. S6. Before mining, drill horizontal holes in the rock drilling tunnel 6 and blast to form the cutting tunnel 12. The boundary of the cutting tunnel 12 is consistent with the thickness of the intercolumn, forming the bottom space 15. S7. After leaving a bottom pillar at the bottom of the cutting tunnel 12, construct the cutting shaft 13 vertically upwards. The boundary of the cutting shaft 13 extends 5 beyond the ore body. S8. Construct upward fan-shaped holes in the upper pillar ore body 5 within the rock drilling tunnel 6, using the cut-up well as the free face, the cut-up cross tunnel as the compensation space, and the funnel as the ore falling structure for medium-deep hole blasting. S9. Ventilate the working face. The airflow enters the electric scraper roadway 7 from the lower middle section, enters the mining area through the bucket neck 9 and the bucket through the bucket 8. After scouring, it is discharged into the upper middle section through the electric scraper roadway 7 and the upper section of the rock drilling roadway 6. S10. After blasting, the ore enters the electric scraper channel 7 through the funnel, and is then removed and transported out using an electric scraper. S11. After the ore in the mining area is cleared, install the filling pipe and dewatering pipe; S12. Construct the filling retaining wall for the electric scraper road 7, rock drilling road 6, pedestrian connecting road and chute 11 that connect with the lower middle section, and then fill the empty area in sections.

[0047] By transforming the original ventilation and pedestrian well in S2 into a rock drilling tunnel 6, the problems of high cost, long construction period, and insufficient space in the original well affecting rock drilling efficiency caused by the traditional need to excavate a new rock drilling tunnel 6 are solved. This allows the well to serve two purposes, which helps to reduce the amount of tunnel excavation, lower costs, and take into account both construction convenience and safety.

[0048] By constructing an electric scraper roadway 7 parallel to and aligned with the drilling roadway 6 in the lower part of the inter-column drilling roadway 6 in S3, from the horizontal plane of this middle section to the horizontal plane of the next middle section, the problem of ore not being able to flow by itself in the gently dipping ore body 5 and the lack of a dedicated ore discharge channel was solved. This, in turn, built a stable foundation for electric scraper operation and shortened the subsequent ore transport path, which is conducive to improving ore transfer efficiency.

[0049] By constructing the bucket tunnel 8 laterally from the electric scraper 7 in S4 and the bucket neck 9 upward from the bucket tunnel 8 to connect with the rock drilling tunnel 6, the problems of the fault connecting the rock drilling tunnel 6 for ore falling and the electric scraper 7 for ore exiting, as well as the long ore transportation distance, are solved. This forms a complete ore transfer channel, which is conducive to improving ore extraction efficiency.

[0050] By coordinating the spatial operations of S2 (modified rock drilling tunnel 6), S3 (construction electric scraper roadway 7), and S4 (construction bucket tunnel 8 and bucket neck 9), the pain point that the ore in the gently inclined ore body 5 could not be self-flowed and could not be equipped with trackless equipment was solved.

[0051] Through the collaboration of S2, S3, S4 and S9, the problems of additional excavation of return airway for mining ventilation, high cost and easy damage to surrounding rock, and uneven air intake leading to insufficient local ventilation were solved.

[0052] In some implementations, refer to Figure 1 In step S5, if the electric scraper track 7 intersects with the existing cross-cutting vein 3, a platform drain 10 is directly installed at the intersection to release ore, thus eliminating the need for external excavation of a ore pass, saving materials for ore pass excavation, and improving economic efficiency. Cross-cutting vein 3 typically connects directly to the lower transport roadway. The installation of a platform drain 10 at the intersection of the electric scraper track 7 and cross-cutting vein 3 enables direct transfer of ore via the electric scraper track 7, platform drain 10, cross-cutting vein 3, and lower transport roadway, without the need for intermediate transfer via a ore pass.

[0053] In some implementations, refer to Figure 1 In step S5, if the electric scraper track 7 is too long, a pass 11 and a winch chamber are added in the middle of the electric scraper track 7 to divide the inter-pillar into two or three sections for mining. Simultaneously, the cross-cut 3 is extended and connected to the pass 11. Due to limitations in traction force and wire rope strength, the effective scraping distance of the electric scraper is typically 30-50 meters. If the length of the electric scraper track 7 exceeds 60 meters, a single electric scraper needs to pull the scraper bucket across an excessively long distance, resulting in insufficient traction force and increased wear on the wire rope. This causes ore to stagnate in the middle of the electric scraper track 7, affecting mining efficiency. Adding a pass 11 and a winch chamber in the middle can control the length of each section of the electric scraper track 7 to 30-40 meters, ensuring that the ore in each section can be scraped into the pass 11, avoiding stagnation. Correspondingly, the length of the inter-pillar mining is also set according to the length of the electric scraper track 7.

[0054] In some implementations, refer to Figure 2 and Figure 3 Following step S6, this process further includes: S61. Expand the upper part of the bucket neck 9 downwards from the bottom space 15 to form a funnel opening. Directly using the original bucket neck 9 to receive the ore after deep-hole blasting in S8 can easily lead to ore accumulation and blockage at the top of the bucket neck 9 due to its limited upper opening area, especially when the local block size is large or the ore has poor flowability after blasting. By expanding the funnel opening downwards from the additional working surface provided by the bottom space 15, the upper opening area of ​​the bucket neck 9 can be increased, ensuring that the blasted ore can smoothly slide into the bucket neck 9 along the inclined surface of the funnel opening, avoiding ore blockage and ore production interruption.

[0055] In some implementations, refer to Figure 2 After step S61, this process further includes: S62. The waste rock generated from blasting should be piled up at the funnel-shaped opening and leveled to serve as a working platform for drilling in the mining operation. Transporting the waste rock away would require additional electric scrapers to transfer it to the ore pass, and then transporting it out by electric locomotive, adding 3-5 working hours and consuming mining equipment resources, leading to delays in subsequent ore recovery. Pile the waste rock directly at the funnel-shaped opening to save on waste rock disposal costs, while also providing a stable working platform suitable for the gently dipping ore body for deep-hole drilling in S62, thus achieving cost optimization, efficiency improvement, and safety assurance.

[0056] In some implementations, refer to Figure 4 In step S8, the blasting sequence for medium-deep holes is from bottom to top. When blasting from bottom to top, the lower section of the ore closest to the funnel is blasted first. The lower ore falls into the electric scraper track 7 through the funnel first, creating compensation space for the upper section of the ore. It can slide along the cleared, gentle space at the bottom towards the funnel, avoiding accumulation and blockage.

[0057] In some implementations, refer to Figure 4In step S8, the medium-deep hole blasting adopts a row-by-row, segmented micro-differential blasting method. When detonating row by row, a new free surface will be formed after the front row of blast holes is blasted. The rear row of blast holes will be detonated based on this free surface. The blasting stress wave can directly act on the unblasted ore body. At the same time, the cracks generated by the front row of blasting will be superimposed with the stress wave of the rear row, making the ore body more fully broken.

[0058] In some implementations, refer to Figure 1 In step S10, if the surrounding rock of the stope has poor stability, only a portion of the ore is extracted after each blast, with the remaining ore temporarily left in the goaf until all blasting is completed. When the surrounding rock of the stope has poor stability, the goaf is prone to cracks and expansion due to the unloading effect after exposure, eventually leading to spalling and roof collapse. Extracting only a portion of the ore after each blast, with the remaining ore temporarily left in the goaf, allows the temporarily left ore to generate lateral passive pressure due to its own weight. This pressure can counteract the compressive stress of the surrounding rock on the goaf, preventing the expansion of cracks in the surrounding rock, effectively providing temporary support for the surrounding rock and maintaining the stability of the goaf's shape.

[0059] In some implementations, refer to Figure 1 In step S11, the void is divided into two parts, and two filling pipes are installed with their outlets separately located at the center of the two parts of the void. The cemented tailings slurry is a Bingham fluid, and its diffusion radius in the void is limited. If the slurry diffuses from a single outlet, dead corners are easily formed at the edge of the void. However, by dividing the void into two parts and arranging one filling pipe at the center of each section, the diffusion radius of the slurry in the two pipes can evenly cover the entire void. The top of the void is prone to becoming an empty top due to insufficient slurry flow. With two filling pipes delivering slurry upwards from the center of the two parts respectively, the slurry can flow along the top plate of the void to both sides, avoiding the situation where the slurry cannot reach the top due to excessive path length and pressure attenuation when delivered by a single pipe.

[0060] In some implementations, refer to Figure 1 In step S12, the bottom plate of the void area to the predetermined height of the filling retaining wall is filled with low-ash sand-to-cement cemented filling, and the section from the predetermined height to the top height is filled with tailings. The lower part of the void area needs to bear the weight of the upper filling body and the mining pressure of the subsequent mining of adjacent pillars, so it needs to have a certain compressive strength.

[0061] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

[0062] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A process for subsequent backfilling and recovery of deep holes in inter-mining pillars of gently dipping, medium-thick ore bodies, characterized in that... include: S1. Select the pillar between two mined and filled ore chambers as the mining pillar; S2. The original ventilation and pedestrian shaft of the mine is brushed and transformed into a rock drilling tunnel. The ventilation and pedestrian shaft is set parallel to the dip of the ore body and located directly below the intercolumn. S3. In the lower part of the rock drilling tunnel in the column, construct an electric scraper track from the horizontal plane of this middle section to the horizontal plane of the next middle section. The electric scraper track is parallel to the rock drilling tunnel and has the same direction. S4. Construct the bucket tunnel laterally from the electric scraper track, and construct the bucket neck upward from the bucket tunnel to connect with the rock drilling tunnel, and the construction progress of the bucket tunnel and the bucket neck should be consistent with that of the electric scraper track. S5. A ore pass and an electric scraper winch chamber shall be installed near the horizontal level of this middle section of the electric scraper track; S6. Before mining, drill horizontal holes laterally in the rock drilling tunnel, and blast to form a cutting tunnel. The boundary of the cutting tunnel is consistent with the thickness of the pillar, forming a bottom-pulling space. S7. After leaving a bottom pillar at the bottom of the cutting tunnel, construct the cutting shaft vertically upwards, with the boundary of the cutting shaft extending beyond the ore body. S8. Construct upward fan-shaped holes in the upper pillar ore body within the rock drilling tunnel, using the cut-up well as the free face, the cut-up cross tunnel as the compensation space, and the funnel as the ore falling structure for medium-deep hole blasting. S9. Ventilate the working face. The airflow enters the electric scraper roadway from the lower middle section, enters the mining area through the bucket neck, and after scouring, is discharged into the upper middle section through the electric scraper roadway and the upper section of the rock drilling roadway. S10. After blasting, the ore enters the electric scraper channel through the funnel, and is then removed and transported out using an electric scraper. S11. After the ore in the mining area is cleared, install the filling pipe and dewatering pipe; S12. Construct the electric scraper road, rock drilling tunnel, pedestrian connecting road, and chute filling retaining wall that connects with the lower middle section, and then fill the empty area in sections.

2. The deep-hole subsequent backfilling and recovery process for inter-mining pillars in gently dipping medium-thick ore bodies according to claim 1, characterized in that, In step S5, if the electric scraper path intersects with the existing cross-cutting vein, a platform is set up at the intersection to allow ore to be released.

3. The deep-hole subsequent backfilling and recovery process for inter-mining pillars in gently dipping medium-thick ore bodies according to claim 2, characterized in that, In step S5, if the electric scraper path is too long, a chute and a winch chamber are added in the middle of the electric scraper path to divide the intercolumn into two or three sections for mining, and at the same time, the cross-section is extended to connect with the chute.

4. The deep-hole subsequent backfilling and recovery process for inter-mining pillars in gently dipping, medium-thick ore bodies according to claim 1, characterized in that, Following step S6, this process further includes: S61. Expand the upper part of the bucket neck downwards from the bottom space to form a funnel mouth.

5. The deep-hole subsequent backfilling and recovery process for inter-mining pillars in gently dipping medium-thick ore bodies according to claim 4, characterized in that, After step S61, this process further includes: S62. The waste rock produced by blasting is piled up at the funnel opening and leveled to be used as a working platform for mining and drilling.

6. The deep-hole subsequent backfilling and recovery process for inter-mining pillars in gently dipping medium-thick ore bodies according to claim 1, characterized in that, In step S8, the blasting sequence for medium-deep holes is from bottom to top.

7. The deep-hole backfilling and recovery process for inter-mining pillars in gently dipping medium-thick ore bodies according to claim 6, characterized in that, In step S8, the medium-deep hole blasting adopts a row-by-row, segmented micro-delay blasting method.

8. The deep-hole subsequent backfilling and recovery process for inter-mining pillars in gently dipping medium-thick ore bodies according to claim 1, characterized in that, In step S10, if the surrounding rock of the mining area has poor stability, only a portion of the ore will be extracted after each blast, and the remaining ore will be temporarily left in the empty area until all blasting is completed and the ore is extracted in a concentrated manner.

9. The deep-hole subsequent backfilling and recovery process for inter-mining pillars in gently dipping medium-thick ore bodies according to claim 1, characterized in that, In step S11, the empty area is divided into two parts, and two filling pipes are provided with their outlets separately arranged at the center of the two parts of the empty area.

10. The deep-hole subsequent backfilling and recovery process for inter-mining pillars in gently dipping medium-thick ore bodies according to claim 1, characterized in that, In step S12, the bottom plate of the subsequent filling of the hollow area is filled with low-ash sand ratio cemented filling up to the predetermined height of the filling retaining wall, and the interval from the predetermined height to the top is filled with tailings.

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