Directional blasting recovery method for point columns in steeply inclined goaf

Abstract

The invention discloses a method for directional blasting recovery of point columns in a steeply inclined goaf, which belongs to the field of mining engineering and comprises the following steps: detecting three-dimensional morphological parameters of the point columns in the goaf; a transverse drift connection roadway is tunneled; constructing blast holes in goaf point columns from the outside of the goaf; charging explosives into the blast holes and detonating ore breaking; and loading and transporting out of a stope through an ore removal funnel in the transverse drift roadway. By detecting the three-dimensional morphological parameters of the goaf point columns, people are directly prevented from being exposed to the goaf collapse environment, and the safety of recovery work is improved; the problem of personnel exposure in the operation stage is solved through the cooperation of tunneling a transverse drift contact roadway, constructing blast holes from the outside to a point column and charging and detonating; therefore, the point column recycling safety is improved; the risk that personnel and equipment need to enter a goaf in the ore transfer stage is avoided through cooperation of the transverse drift connection roadway and ore removal and loading, so that whole-process external operation is ensured, and the problem that the personnel and the equipment are exposed in the goaf in point column recovery work is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of mining engineering, and in particular relates to a method for recovering point columns by directional blasting in a steeply inclined empty area. Background Art

[0002] In mining engineering, point pillars are regularly arranged ore bodies or rock pillars reserved for underground mining to support the roof. They are typically square or rectangular in shape, ranging from 3–7 meters (thin ore bodies) to 5–10 meters (thick ore bodies), with center-to-center spacing of 8–14 meters. Their core function is to form a support structure by partially retaining ore, preventing roof collapse in the goaf and ensuring operational safety. Point pillars are commonly used in room-and-pillar and point-and-pillar-and-fill mining methods, and are particularly widely used in gently inclined, medium-thick ore bodies. In steeply inclined ore bodies, point pillars can account for up to 15%–20% of the ore, making the existing goaf narrow and impractical for conventional recovery techniques, resulting in permanent losses far exceeding design values. Existing recovery techniques, such as artificial false lanes, require personnel to enter the goaf and conduct exposed work, violating safety regulations.

[0003] Therefore, there is an urgent need for a point column recovery method for narrow goafs without the need for personnel to enter. Summary of the Invention

[0004] In view of the technical problems existing in the background technology, the present application provides a method for point column directional blasting recovery in a steeply inclined empty area, comprising: Detect the three-dimensional morphological parameters of the point columns in the goaf; Excavate the connecting tunnel through the vein; Point-column blasthole construction from outside the goaf to the goaf; Loading blastholes and blasting the ore; The ore is loaded onto trucks and transported out of the mining area through the ore discharge funnel in the vein tunnel.

[0005] In some embodiments, the method of constructing a blasthole in a goaf includes: Transport the medium-long hole drilling rig to the end of the vein connecting tunnel or into the vein tunnel.

[0006] In some embodiments, after the medium-long hole drilling rig is transported to the end of the vein connecting tunnel or into the vein tunnel, the point column construction blasthole in the goaf further includes: Use medium-deep hole drilling rigs to construct lateral fan-shaped blasthole groups until the blasthole length reaches the junction of the ore body and the hanging wall surrounding rock.

[0007] In some embodiments, the three-dimensional morphological parameters of the detected goaf point column include: The three-dimensional laser scanning technology is used to perform full-section scanning of the goaf formed by the shallow hole ore retention method, generate a point cloud model, and capture the position, size and shape of the point columns.

[0008] In some embodiments, after detecting the three-dimensional morphological parameters of the point pillars in the goaf, the method for recovering the point pillars in the steeply inclined goaf by directional blasting further comprises: Project the three-dimensional coordinates of the point column onto the horizontal plane to determine its corresponding area in the vein tunnel.

[0009] In some embodiments, in the excavation and penetration connecting tunnel, the following steps are included: A vein-crossing connecting tunnel is excavated from the vein-crossing tunnel to the projection point.

[0010] In some embodiments, the excavation and penetration tunnel includes: Excavate through the vein connecting tunnel to the projection boundary position of the point column.

[0011] In some embodiments, the excavation and penetration tunnel includes: Excavate the vein connecting tunnel to the boundary position of the point column projection, and construct the rock drilling tunnel along the vein in the width direction of the point column projection until the boundary of the rock drilling tunnel along the vein exceeds the boundary in the width direction of the point column projection.

[0012] In some embodiments, charging the blasthole and blasting the ore include: Charge the point column ore body section, leave the lower wall surrounding rock section empty, and use gun mud to block the junction between the explosives and the surrounding rock section.

[0013] In some embodiments, the method of charging the blasthole and blasting the ore further comprises: The micro-difference blasting method is used to carry out directionally detonating the explosives in the lateral fan-shaped medium-deep holes.

[0014] The present invention provides a method for directional blasting recovery of point pillars in a steeply inclined void. By detecting the three-dimensional morphological parameters of the point pillars in the void, the risk of personnel entering the void during the detection phase is avoided, and non-contact data collection is used instead of manual survey to directly avoid exposure of personnel to the collapse environment of the void, thereby improving the safety of the recovery work; the problem of personnel exposure during the operation phase is solved by the collaboration of excavating a vein-penetrating connecting tunnel, constructing blastholes from the outside to the point pillars, and loading and detonating, and then by constructing a physical isolation channel, the equipment operation is carried out outside the goaf for directional blasting and ore dropping, and the tunnel barrier is used to ensure that personnel are away from the interior of the void, thereby avoiding the possibility of collapse accidents from the source; thereby improving the safety of point pillar recovery; the risk of personnel and equipment entering the void during the ore transportation phase is solved by the collaboration of the vein-penetrating connecting tunnel and the ore loading, and then the ore after blasting is directly collected in the vein-penetrating tunnel for loading by pre-setting an integrated mining and transportation path, and the dual function of the tunnel is used to reduce the need for a temporary construction system, thereby ensuring external operation throughout the entire process, and thereby avoiding the problem of personnel and equipment being exposed to the goaf during the point pillar recovery work.

[0015] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] To more clearly illustrate the technical solution of this application, the following is a brief introduction to the drawings used in this application. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0017] Figure 1 This is a schematic structural diagram of the working conditions used in a method for point column directional blasting recovery in a steeply inclined empty area provided by an embodiment of the present invention; Figure 2 This is a schematic structural diagram of the arrangement of a mining project for a working condition used in a method for point column directional blasting recovery in a steeply inclined void area provided by an embodiment of the present invention; Figure 3 This is a schematic diagram of a drilling project for a point column in accordance with a working condition applied in a method for recovering a point column by directional blasting in a steeply inclined void area provided by an embodiment of the present invention; Figure 4 This is a schematic diagram of a drilling project for a wide point column in a working condition applied in a method for recovering a point column by directional blasting in a steeply inclined void area provided by an embodiment of the present invention; Figure 5 This is a schematic diagram of the arrangement of point-pillar blastholes in a working condition used in a method for point-pillar directional blasting recovery in a steeply inclined empty area provided by an embodiment of the present invention; Figure 6 This is a basic flow diagram of a method for point column directional blasting recovery in a steeply inclined empty area provided by an embodiment of the present invention; Figure 7 This is a schematic diagram of an optimized process for constructing blastholes with outward-facing point pillars in a goaf, in a method for recovering point pillars by directional blasting in a steeply inclined goaf provided by an embodiment of the present invention; Figure 8 This is a schematic diagram of a further optimized process for constructing blastholes with outward-facing point pillars in a goaf, in a method for recovering point pillars by directional blasting in a steeply inclined goaf provided by an embodiment of the present invention; Figure 9 This is a schematic diagram of an optimized flow chart of a detection method for a method of point column directional blasting recovery in a steeply inclined empty area provided by an embodiment of the present invention; Figure 10This is a schematic diagram of a further optimized flow chart of a detection method for a method for recovering point pillars by directional blasting in a steeply inclined empty area provided by an embodiment of the present invention; Figure 11 This is a schematic diagram of an optimized flow chart of a mining project layout for a method of point column directional blasting recovery in a steeply inclined void area provided by an embodiment of the present invention; Figure 12 This is a schematic diagram of a further optimized process flow for the arrangement of mining engineering for a method for point column directional blasting recovery in a steeply inclined void area provided by an embodiment of the present invention; Figure 13 This is a schematic diagram of an optimized process flow for the arrangement of mining engineering for wide point pillar mining in a method for recovering point pillars by directional blasting in a steeply inclined void area provided by an embodiment of the present invention; Figure 14 This is a schematic diagram of a blasting process for a method for recovering point columns by directional blasting in a steeply inclined empty area provided by an embodiment of the present invention; Figure 15 The present invention provides a schematic diagram of an optimized blasting process for a method of point column directional blasting recovery in a steeply inclined empty area.

[0018] Explanation of the accompanying reference numerals: 10, through-vein tunnel; 20, ore drawing funnel; 30, goaf; 40, point column; 50, lateral fan-shaped medium-deep hole; 60, through-vein connecting tunnel; 70, rock drilling tunnel along the vein. DETAILED DESCRIPTION

[0019] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0021] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0022] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0023] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0024] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0025] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0026] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0027] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0028] Reference Figure 1 and Figure 2, for example, an application scenario of a method for directional blasting recovery of point pillars in a steeply inclined empty area is provided, wherein the point pillars 40 in the goaf 30 to be mined are located in the middle of the goaf 30, and a through-vein tunnel 10 is pre-drilled at the bottom of the ore body, and the through-vein tunnel 10 is aligned with the bottom direction of the ore body; a hopper 20 is provided at the top of the through-vein tunnel 10 to receive the ore dropped from the point pillars 40 and to load the ore out of the through-vein tunnel 10; a through-vein connecting tunnel 60 is excavated in the vertical direction of the bottom through-vein tunnel 10 to the same horizontal plane as the through-vein tunnel 10, the significance of which is to provide mining for medium and deep hole drilling rigs. The working surface outside the empty area 30 is constructed to protect the safety of equipment and personnel; when the width of the point column 40 is large, a vein drilling tunnel 70 is constructed at the end of the vein connecting tunnel 60 along the direction of the point column 40, so as to avoid the limitation of the edge blasthole angle due to insufficient tunnel length; after that, a medium-depth hole drilling rig is used to construct a lateral fan-shaped medium-depth hole 50 in a directional manner towards the position of the point column 40 in the empty area, and the edge of the lateral fan-shaped medium-depth hole 50 is located at the boundary between the ore body and the upper wall surrounding rock; the lateral fan-shaped medium-depth hole 50 is filled with explosives in the ore body part of the point column 40 for directional detonation.

[0029] Reference Figure 6 A method for recovering material by directional blasting in a steeply inclined empty area comprises: S101. Detect the three-dimensional morphological parameters of the point pillars in the goaf. Specifically, the core of this step is to provide a spatial data foundation for subsequent blasting design. Non-contact data collection replaces traditional manual surveying, eliminating the need for personnel to enter the goaf for data collection. Non-contact measurement methods are used to obtain the spatial coordinates, dimensions, and inclination parameters of the point pillars. A three-dimensional model is then constructed to accurately locate the blasting target, preventing blasting design errors caused by missing data. Exemplarily, a hexacopter drone chassis is equipped with a 360-degree rotating laser scanner, and a high-precision inertial guidance system synchronizes flight attitude and scanning angle in real time. During flight, the laser scanner emits a pulsed laser beam along a preset spiral trajectory across the entire goaf, calculating the spatial coordinates by receiving reflected light signals from the point pillars' surfaces. Simultaneously, the drone uses obstacle avoidance radar to dynamically adjust its trajectory to avoid obstacles. Ultimately, the point cloud data is transmitted back to a ground processing terminal in real time, generating a three-dimensional model of the point pillars and annotating key inclination parameters. Exemplarily, a retractable carbon fiber probe is used to drill deep into the goaf, with a dual sensor at the end consisting of a sonar transmitter and a narrow-beam laser scanner. The sonar module emits high-frequency sound waves to detect the underwater contours of the point column, while the laser module simultaneously scans the exposed surface. By fusing the sound wave reflection time with the laser ranging data, a complete 3D point cloud of the point column is generated, automatically annotating structures below the water level. For example, a panoramic laser scanner mounted on a tracked trolley covers the boundaries of the goaf along a pre-set track. As the robot moves along the track, the scanner emits a laser beam in a vertical fan-shaped pattern, and an encoder is used to record the travel distance and scanning angle. Multi-site cloud stitching technology eliminates blind spots, and a point column boundary recognition algorithm is used to extract the column diameter, height, and deflection angle.

[0030] S102: Excavate a connecting tunnel through the vein. Specifically, this step aims to establish a safe working passageway, ensuring that personnel and equipment remain outside the goaf. Tunneling creates a path laterally connected to the point column, providing a physical access point for external blasthole construction. This ensures that the working surface is isolated from the goaf, thus minimizing the risk of personnel being exposed to goaf collapse.

[0031] S103, construct blastholes from the outside of the goaf to the point column of the goaf; specifically, this step is the core operation to achieve remote blasting and ore dropping. The blasthole orientation and depth are accurately designed based on three-dimensional morphological parameters, so that the blastholes penetrate from the stable surrounding rock area to the inside of the point column. Directional drilling technology is used to control the direction of energy transfer to ensure that the blasting energy is concentrated on the target point column, reduce the disturbance to the surrounding rock mass, and prevent personnel from entering the goaf through external drilling. For ease of understanding, for example, refer to Figure 2 and Figure 3 As shown, a point column 40 is drilled from the inner side of the vein connecting tunnel 60 into the goaf 30, and a lateral fan-shaped medium-depth hole 50 is formed.

[0032] S104: Charge the blasthole and detonate to release the ore. Specifically, this step aims to dissociate the point pillar ore and control the blasting range. By externally loading explosives and implementing directional detonation, the point pillar is broken into a pre-set shape, exploiting the structural weaknesses of the point pillar to achieve controlled collapse, thereby reducing the damage to the stability of the goaf roof caused by blasting vibration.

[0033] S105: Load the ore from the goaf into the mine tunnel through the ore discharge hopper and transport it out of the mine. This step is to complete the ore transfer from the goaf to the tunnel through the pre-installed ore discharge system, thereby preventing personnel or equipment from entering the goaf and improving the safety of mining operations.

[0034] S101 and S103 of this application have a collaborative relationship: S101 obtains the spatial coordinates, dimensions, and inclination parameters of the point column through non-contact measurement (such as drone laser scanning or probe sonar fusion) and establishes a three-dimensional model. S103 accurately designs the blasthole orientation and depth based on this model, so that the blasthole penetrates from the stable surrounding rock area to the interior of the point column. The collaborative relationship between the two is reflected in the use of data-driven blasting design: the three-dimensional morphological parameters provided by S101 provide a spatial data basis for the blasthole positioning of S103, and the direction of energy transfer is controlled through directional drilling technology to ensure that the blasting energy is concentrated on the target point column, reducing the disturbance to the surrounding rock mass, thereby avoiding the blasting design deviation problem caused by data missing in the goaf, and then avoiding ineffective drilling or energy waste, and improving blasting accuracy and resource recovery rate.

[0035] S102 of the present application has a collaborative relationship with S103 and S104: S102 constructs a through-vein connecting tunnel to form an operating channel that is laterally connected to the point column, and S103 and S104 construct blastholes from the outside to the point column through the tunnel and load explosives for detonation. The collaborative relationship between the two is the coordination of physical channels and operational safety: the tunnel serves as an isolation barrier, so that personnel and equipment are always located outside the goaf, providing a safe physical operating space for S103 and S104. External construction and internal action are achieved through tunnel excavation, which avoids exposure of personnel to the goaf from the source and avoids the risk of collapse. This collaboration avoids the problem of personnel entering dangerous areas in traditional steeply inclined thin ore body point column mining operations, while providing a stable construction environment for directional blasting and reducing roof instability accidents.

[0036] S103 and S104 in this application collaborate: S103 designs the blasthole orientation and depth based on a three-dimensional model, while S104 implements directional detonation using external charges. This collaboration is manifested in the following: S103's blasthole penetration path, combined with the inherent structural weaknesses of the point column (such as inclination parameters), allows S104's blasting energy to dissociate the ore in a preset pattern. The blasthole guides the blast wave along the internal fissures of the point column, achieving controlled collapse. This collaboration reduces damage to the goaf roof caused by blasting vibrations, avoids surrounding rock instability caused by energy diffusion, and improves ore crushing efficiency.

[0037] There is a collaborative relationship between S101 and S105 in this application: the point column three-dimensional model generated by S101 marks the key inclination angles and structural parameters, while S105 loads and transports the ore through the ore discharge funnel of the vein tunnel. The collaboration between the two is that the model guides the resource recovery path: the three-dimensional model accurately locates the spatial distribution of collapsed ore, providing a basis for the layout of the ore discharge funnel of S105. By optimizing the ore discharge points, it is ensured that the ore is efficiently gathered to the transportation channel. This collaboration solves the problem of low recovery efficiency caused by the scattered distribution of low-grade ore bodies, avoids equipment from entering empty areas, and improves transportation safety.

[0038] In this application, S102 and S105 collaborate: S102's inter-vein connecting tunnel provides a pre-set ore exit channel for S105, forming an integrated mining and transportation system. The tunnel serves as both a blasting operation channel and an ore transfer route. During excavation, the transportation route is planned so that after blasting, the ore directly enters the inter-vein tunnel through the inter-vein connecting tunnel for loading. This collaboration reduces secondary development costs, solves the problem of requiring a temporary system for ore transfer in the goaf, and prevents personnel and equipment from entering the goaf, achieving full external operation.

[0039] This application solves the risk of personnel entering the goaf during the detection phase by detecting the three-dimensional morphological parameters of the point pillars in the goaf, and then replaces manual surveys with non-contact data collection to directly avoid personnel exposure to the collapse environment of the goaf, thereby improving the safety of the recovery work; the problem of personnel exposure during the operation phase is solved by the collaboration of excavating through-vein connecting tunnels, constructing blastholes from the outside to the point pillars, and loading and detonating them, and then by constructing a physical isolation channel, the equipment operation is carried out outside the goaf for directional blasting and dropping ore, and the tunnel barrier is used to ensure that personnel are away from the inside of the goaf, thereby avoiding the possibility of collapse accidents at the source; thereby improving the safety of point pillar recovery; the risk of personnel and equipment entering the goaf during the ore transportation phase is solved by the collaboration of through-vein connecting tunnels and ore loading, and then by pre-setting integrated mining and transportation paths, the ore after blasting is directly collected in the through-vein tunnel for loading, and the dual functions of the tunnel are used to reduce the need for temporary construction systems, thereby ensuring external operations throughout the entire process, and thus avoiding the problem of personnel and equipment being exposed to the goaf during point pillar recovery work.

[0040] In some embodiments, reference Figure 7 , in S103, constructing blastholes from the outside of the goaf to the point columns in the goaf, including: S1031, transporting the medium-deep hole drilling rig to the end of the through-vein connecting tunnel or into the through-vein tunnel. Specifically, the medium-deep hole drilling rig is positioned in the through-vein connecting tunnel or into the through-vein tunnel, and the physical isolation space pre-formed in the through-vein connecting tunnel is used as the drilling rig transportation channel and working platform, so that the drilling rig can complete the blasthole directional construction in the stable surrounding rock area, thereby avoiding personnel from entering the goaf for drilling operations. This design relies on the isolation effect of the tunnel space on the dangerous area of ​​the goaf, limiting the drilling operation to the external surrounding rock stable area, and at the same time, through the spatial relative position relationship between the tunnel end or the through-vein tunnel and the point column, it ensures that the blasthole accurately penetrates from the outside to the inside to the point column target position, providing a precise energy transfer path for subsequent directional blasting.

[0041] In some embodiments, reference Figure 8After the medium-deep hole drilling rig is transported to the end of the vein connecting tunnel or into the vein tunnel, S103, constructing blastholes from the outside of the goaf to the point column of the goaf, also includes: S1032, using the medium-deep hole drilling rig to construct a lateral fan-shaped blasthole group until the blasthole length reaches the boundary between the ore body and the upper wall surrounding rock. The purpose of this step is to construct a geometric channel for directional energy transmission, and through the geometric layout of the lateral fan-shaped blasthole group, the blasting energy is accurately focused on the point column area to avoid disorderly diffusion of energy. Its role is reflected in two aspects: on the one hand, the fan-shaped radial blasthole group covers the cross section of the point column to form a spatial convergence point of blasting energy, giving priority to destroying the internal structural weaknesses of the point column, realizing directional collapse "from the inside to the outside", and reducing the impact on the surrounding rock; on the other hand, the blasthole length is controlled to strictly end at the junction of the ore body and the upper wall surrounding rock, blocking the transmission path of the blasting stress wave to the surrounding rock, geometrically limiting the disturbance range, forming a natural energy reflection barrier, inhibiting the transmission of stress waves to the roof and floor of the goaf, and maintaining the stability of the surrounding rock. For example, combined with Figure 3 or Figure 4 , drilling from the vein connecting tunnel 60 into the point column 40 in the goaf 30, and forming a lateral fan-shaped medium-deep hole 50.

[0042] In some embodiments, reference Figure 9 In S101, detecting the three-dimensional morphological parameters of the point pillars in the goaf includes: S1011, using 3D laser scanning technology to perform a full-section scan of the goaf formed by the shallow hole ore retention method, generating a point cloud model to capture the position, size, and morphology of the point pillars. The purpose of this step is to establish a non-contact perception system for goaf spatial data. Remote scanning replaces traditional manual surveys, providing a precise spatial reference for subsequent blasting design and eliminating the need for personnel to enter the goaf. Specifically, this involves the holographic acquisition of 3D data: relying on the principles of laser ranging and polar coordinate measurement, a high-speed pulsed laser beam is used to scan the goaf surface, and the 3D coordinates of each point on the point pillar surface are calculated by receiving the reflected signal. The point cloud model automatically fits the point pillar boundaries and morphological parameters using a spatial data reconstruction algorithm, enabling non-destructive capture of hidden structures (such as contours below the water level line). Furthermore, a full-section scan is performed across the entire goaf to generate a point cloud model that fully maps the spatial coordinates, geometric dimensions, and structural inclination of the point pillars, providing an irreplaceable data foundation for directional blasting design.

[0043] In some embodiments, reference Figure 10After detecting the three-dimensional morphological parameters of the point pillars in the goaf at step S101, the method for recovering the point pillars by directional blasting in the steeply inclined goaf further includes: S1012, projecting the three-dimensional coordinates of the point pillars onto a horizontal plane to determine their corresponding areas within the through-vein roadway. The purpose of this step is to establish a spatial mapping benchmark. By projecting the three-dimensional coordinates of the point pillars onto a horizontal plane, the distribution area of ​​the collapsed ore within the through-vein roadway can be located. This provides a geometric positioning basis for the closed transportation system, defines the shortest path for ore transfer, and reduces the frequency of equipment movement and contact with the roadway surrounding rock.

[0044] In some embodiments, reference Figure 11 , in S102, excavating the vein-penetrating connecting tunnel, including: S1021, excavating the vein-penetrating connecting tunnel from the vein-penetrating tunnel to the projection point. The purpose of this step is to establish a data-driven physical channel precision docking mechanism to accurately guide the spatial layout of tunnel construction. Specifically, using the horizontal projection point obtained in S1012 as the spatial target, the vein-penetrating connecting tunnel is directionally excavated from the vein-penetrating tunnel to ensure that the connecting tunnel is accurately penetrated to the predetermined position on the side of the point column, creating an adaptive working space for subsequent blasthole construction; on the other hand, the precise excavation based on the projection point greatly reduces the amount of invalid rock excavation, and only a connecting tunnel with the shortest straight path needs to be formed between the vein-penetrating tunnel and the projection point. This not only reduces the mechanical disturbance to the surrounding rock, but also avoids the risk of goaf stability caused by over-excavation or deviation of the tunnel.

[0045] In some embodiments, reference Figure 12 , in S102, excavating the vein-penetrating connecting tunnel, including: S1022, excavating the vein-penetrating connecting tunnel to the projection boundary position of the point column. Specifically, after detecting and obtaining the point column morphological parameters and generating a horizontal projection, the projection boundary position directly calibrates the maximum contour range of the point column on the horizontal plane. The essence of excavating the tunnel to this boundary position is to establish a physical channel and working platform for subsequent blasthole construction, so that the blasthole group can obtain a relatively preferred working surface to optimize the blasthole angle and blasthole position as much as possible, which is conducive to the blasting mining of point columns in the goaf. For example, if the tunnel does not reach the projection boundary, the blasthole needs to penetrate thicker rock layers obliquely to cover the point column, which not only increases the difficulty of drilling, but also disperses the blasting energy; after accurately positioning to the boundary, the blasthole can be directly expanded along the lateral fan shape to ensure that the explosive energy is efficiently concentrated on the point column body, thereby improving the blasting effect. For ease of understanding, for example, refer to Figure 2 , excavate the vein connecting tunnel 60 from the vein tunnel 10 to the projection boundary position of the point column 40.

[0046] In some embodiments, reference Figure 13, in S102, excavating the vein-penetrating connecting tunnel, including: S1023, excavating the vein-penetrating connecting tunnel to the boundary position of the point column projection, and constructing the rock drilling tunnel along the vein in the width direction of the point column projection to the boundary of the rock drilling tunnel along the vein beyond the boundary in the width direction of the point column projection. Specifically, after excavating the vein-penetrating connecting tunnel to the boundary position of the point column projection, the rock drilling tunnel is extended along the width direction of the point column to make its length exceed the boundary of the point column projection, so that when facing a point column with a larger width, the ultra-wide extended rock drilling tunnel allows the blastholes to be evenly arranged at a fan-shaped angle pointing to the center of the point column, avoiding the limitation of the edge blasthole angle due to insufficient tunnel length. For ease of understanding, for example, refer to Figure 2 , excavate the vein-penetrating connecting tunnel 60 from the vein-penetrating tunnel 10 to the projection boundary position of the point column 40, and then construct the vein-penetrating rock tunnel 70 in the projection width direction of the point column, and until the boundary of the vein-penetrating rock tunnel 70 exceeds the boundary in the projection width direction of the point column 40.

[0047] In some embodiments, reference Figure 14 , in S104, charging explosives into the blasthole and blasting the ore, including: S1041, charging explosives in the point pillar ore body section, leaving the footwall surrounding rock section empty, and using gun mud to block the junction between the explosives and the surrounding rock section. Specifically, charging is limited to the point pillar ore body section, that is, the explosives are concentrated inside the point pillar ore to be recovered, so as to improve the efficiency of the blasting energy in crushing the ore body and avoid the energy from spreading to non-target areas; and leaving the footwall surrounding rock section empty means that the part of the blasthole extending to the footwall surrounding rock after passing through the point pillar remains in a charge-free state. If explosives are loaded in the surrounding rock, part of the energy will be consumed in crushing non-target rock, reducing the quality of ore crushing and causing over-excavation problems. This step is based on the three-dimensional coordinates of the ore pillar provided in S101. By strictly constraining the blasting energy to the target ore body, it not only improves the blasting efficiency and resource recovery rate, but also maintains the stability of the stope and avoids the chain risk caused by surrounding rock damage. Gun mud plugging is to fill the junction of explosives and surrounding rock with inert materials (such as a mixture of clay and sand), using its compressibility and sealing properties to block the escape of explosive gas into the cracks of the surrounding rock, while increasing the effective working time of the explosive gas on the ore body and enhancing the uniformity of ore crushing.

[0048] In some embodiments, reference Figure 15, in S104, charging explosives into the blastholes and detonating the falling ore, including: S1042, using micro-difference blasting to directionally detonate the explosives in the lateral fan-shaped medium-deep holes. Specifically, the core of this technical solution is to solve the problems of blasting disturbance control and ore crushing efficiency in the point column recovery process by controlling the release direction of blasting energy through timing. Specifically, micro-difference blasting designs the detonation time interval of adjacent blastholes so that the explosion stress wave forms a superposition effect in the ore body, guiding the blasting energy to concentrate on the central area of ​​the point column. On the one hand, it promotes the full crushing of the point column ore body along the preset free surface, and on the other hand, the mutual offset mechanism of stress waves is used to reduce the vibration impact on the surrounding rock of the goaf. For example, the detonation time interval of micro-difference blasting is set to 50 milliseconds.

[0049] The surrounding rock in steeply inclined goafs is prone to slippage and collapse due to blasting vibrations. Micro-difference blasting decomposes the total blast energy into multiple, smaller bursts, shifting the primary vibration frequency to a non-resonant frequency band and reducing vibration intensity. Furthermore, the targeted energy concentration ensures that the point pillars are fully shattered in one go, avoiding cumulative damage to the goaf's stability from secondary blasting. This method achieves efficient, low-disturbance recovery of the point pillars without requiring personnel to enter the goaf.

[0050] In some embodiments, reference Figures 1 to 5 For example, a thin vein segmented medium-deep hole multi-directional coordinated ore drop mining method includes the following steps: S1. Use three-dimensional laser detection technology to detect the goaf 30 formed by shallow hole mining of steeply inclined ore bodies, and accurately determine the three-dimensional shape of the goaf 30 and the position, size, shape and other information of the point columns 40 in the goaf 30.

[0051] S2. According to the specific position of the point column 40 in the goaf 30 , its projection area in the horizontal direction is correspondingly determined, and a through-vein connecting tunnel 60 is excavated in the through-vein tunnel 10 toward the projection position corresponding to the point column 40 .

[0052] Among them, the specifications of the through-vein connecting tunnel 60 are 2m×2m-2.2m×2.2m. The length of the through-vein connecting tunnel 60 is determined according to the position of the point column 40 in the goaf 30. In order to ensure the rock drilling and blasting effect, the through-vein connecting tunnel 60 is constructed as far as possible to the boundary position of the projection of the point column 40.

[0053] When the width of the point column 40 is large, it is necessary to construct a vein drilling tunnel 70 along the direction of the ore body at the end of the vein connecting tunnel 60. The specifications of the vein drilling tunnel 70 are 2.5m×2.5m-3.m×3m. The length of the vein drilling tunnel 70 is determined according to the width of the point column 40. For better construction, its length should be greater than the width of the point column 40.

[0054] S3. At the end of the vein-penetrating connecting tunnel 60 or within the vein-drilling tunnel 70, a medium-length hole drill is used to drill a lateral fan-shaped medium-length hole 50 toward the location of the point pillar 40 within the goaf 30. The lateral fan-shaped medium-length hole 50 should be drilled to the boundary between the point pillar 40 ore body and the hanging wall surrounding rock. The length of the lateral fan-shaped medium-length hole 50 is determined based on the specific location of the point pillar 40 within the goaf 30.

[0055] The row spacing of the blasthole surface lines formed by the lateral fan-shaped medium-deep holes 50 in the point column 40 is 1.2m-1.4m, and the hole bottom distance of the lateral fan-shaped medium-deep holes 50 is 1.4m-1.6m.

[0056] S4. After all directional construction of the lateral fan-shaped medium-deep holes 50 is completed, explosives are loaded into the lateral fan-shaped medium-deep holes 50. Explosives are only loaded in the ore body of the point column 40, and no explosives are loaded in the surrounding rock of the footwall.

[0057] S5. After the charge is loaded, the explosives in the lateral sector-shaped medium-deep hole 50 are blocked with taphole mud to prevent the blasting energy from leaking along the unloaded lateral sector-shaped medium-deep hole 50 during the detonation of the explosives, thereby affecting the blasting effect.

[0058] The length of the gun mud used to seal the explosives in the lateral fan-shaped medium-deep hole 50 is not less than 0.5m.

[0059] S6. Use a micro-difference blasting method to directionally detonate the explosives in the lateral fan-shaped medium-depth holes 50. The detonation order is to first detonate the lateral fan-shaped medium-depth holes 50 on both sides, and then detonate the lateral fan-shaped medium-depth holes 50 in the middle. The detonation order of each row of lateral fan-shaped medium-depth holes 50 is to first detonate the middle blast hole, and then detonate the blast holes at both ends.

[0060] The detonation time interval of the explosives in the lateral fan-shaped medium-deep hole 50 is 50ms.

[0061] S7. The point pillars 40 in the goaf 30 are collapsed by explosive blasting. The collapsed ore falls directly into the goaf 30 and falls into the bottom ore draw hopper 20 by gravity. The ore is loaded into trucks and transported out of the mining area through the ore draw hopper 20 in the vein tunnel 10.

[0062] S8. Repeat steps S3 to S7 in sequence according to the number of the point pillars 40 in the goaf 30 until all the point pillars 40 in the goaf 30 are recovered.

[0063] like Figure 5As shown, in some embodiments of the present invention, the lateral fan-shaped medium-depth holes 50 are arranged in 4 rows, and each row of the lateral fan-shaped medium-depth holes 50 is arranged with 4 blast holes. During blasting, the blasting order is to start blasting by detonating the two middle blast holes in the first row of the lateral fan-shaped medium-depth holes 50, and then blasting the two blast holes at both ends of the first row of the lateral fan-shaped medium-depth holes 50, the two middle blast holes in the fourth row of the lateral fan-shaped medium-depth holes 50, the two blast holes at both ends of the fourth row of the lateral fan-shaped medium-depth holes 50, the two middle blast holes in the second row of the lateral fan-shaped medium-depth holes 50, the two blast holes at both ends of the second row of the lateral fan-shaped medium-depth holes 50, the two middle blast holes in the third row of the lateral fan-shaped medium-depth holes 50, and the two blast holes at both ends of the third row of the lateral fan-shaped medium-depth holes 50.

[0064] The above description is only 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 any technician familiar with this technical field within the technical scope disclosed by the present invention and within the spirit and principles of the present invention should be covered by the scope of protection of the present invention.

[0065] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are merely examples, and any embodiments having substantially the same structure and effect as the technical concept within the scope of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the present application, any other embodiments that can be conceived by those skilled in the art and that combine some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A method for recovering material by directional blasting in a steeply inclined empty area, characterized in that: include: Detect the three-dimensional morphological parameters of the point columns in the goaf; Excavate the connecting tunnel through the vein; Point-column blastholes are constructed from outside the goaf to the goaf; Loading blastholes and blasting the ore; The ore is loaded onto trucks and transported out of the mining area through the ore discharge funnel in the vein tunnel.

2. The method for recovering material by point-column directional blasting in a steeply inclined empty area according to claim 1, characterized in that: The method of constructing a blasthole in the goaf includes: Transport the medium-long hole drilling rig to the end of the vein connecting tunnel or into the vein tunnel.

3. The method for recovering material by point-column directional blasting in a steeply inclined empty area according to claim 2, characterized in that: After the medium-long hole drilling machine is transported to the end of the vein connecting tunnel or into the vein tunnel, the method of constructing blastholes in the goaf also includes: Use medium-deep hole drilling rigs to construct lateral fan-shaped blasthole groups until the blasthole length reaches the junction of the ore body and the hanging wall surrounding rock.

4. The method for recovering material by point-column directional blasting in a steeply inclined empty area according to claim 1, characterized in that: The three-dimensional morphological parameters of the detected goaf point column include: The three-dimensional laser scanning technology is used to perform full-section scanning of the goaf formed by the shallow hole ore retention method, generate a point cloud model, and capture the position, size and shape of the point columns.

5. The method for recovering material by point-column directional blasting in a steeply inclined empty area according to claim 4, characterized in that: After detecting the three-dimensional morphological parameters of the point pillars in the goaf, the method for recovering the point pillars in the steeply inclined goaf by directional blasting further comprises: Project the three-dimensional coordinates of the point column onto the horizontal plane to determine its corresponding area in the vein tunnel.

6. The method for recovering material by point-column directional blasting in a steeply inclined empty area according to claim 5, characterized in that: In the excavation and penetration connecting tunnel, the following are included: A cross-vein connecting tunnel is excavated from the cross-vein tunnel to the projection point.

7. The method for recovering material by point-column directional blasting in a steeply inclined empty area according to claim 5, characterized in that: In the excavation and penetration connecting tunnel, the following are included: Excavate through the vein connecting tunnel to the projection boundary position of the point column.

8. The method for recovering material by point-column directional blasting in a steeply inclined empty area according to claim 5, characterized in that: In the excavation and penetration connecting tunnel, the following are included: Excavate the vein connecting tunnel to the boundary position of the point column projection, and construct the rock drilling tunnel along the vein in the width direction of the point column projection until the boundary of the rock drilling tunnel along the vein exceeds the boundary in the width direction of the point column projection.

9. The method for recovering material by point column directional blasting in a steeply inclined empty area according to claim 1, characterized in that: The method of charging explosives into the blasthole and blasting the ore includes: Charge the point column ore body section, leave the lower wall surrounding rock section empty, and use gun mud to block the junction between the explosives and the surrounding rock section.

10. The method for recovering material by point column directional blasting in a steeply inclined empty area according to claim 9, characterized in that: The process of charging the blasthole and blasting the ore also includes: The micro-difference blasting method is used to carry out directionally detonating the explosives in the lateral fan-shaped medium-deep holes.

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