Opposite-pulling type continuous stoping process for gently-inclined medium-thickness ore body

Abstract

The invention discloses an opposite-pull type continuous stoping process for a gently inclined medium-thickness ore body. The method relates to the technical field of ore extraction, and comprises the following steps: S1, stoping unit division; s2, a mining preparation cutting project is arranged; s3, layered stoping is conducted, and the stopes are oppositely pulled from the vein-following ore removal roadways to the panel boundaries; s31, ore breaking and ore removal are conducted, specifically, ore breaking is conducted through impact type or cutting type rock breaking equipment, and the ore is pushed to the boundary of the stope; s32, ventilating, filling and draining; mining once every three in the stope, circularly propelling, and repeating the previous steps until the stoping of the whole layer is completed; s4, the advancing direction of layered stoping is the direction perpendicular to the inclined line of the ore body from bottom to top until stoping of the whole panel is completed; by modularly dividing the stoping units, optimizing the stoping preparation engineering arrangement and adopting the opposite-pull type continuous stoping process, the collaborative operation of mechanical continuous mining and timely filling of the goaf is realized, and the problems of low resource recovery rate, poor stope stability, limited production efficiency and the like in the traditional method are effectively solved; the method has the advantages of improving the mining efficiency, enhancing the stope stability and optimizing the resource recovery rate.

Description

Technical Field

[0001] This application relates to the field of ore mining technology, and in particular to a pull-type continuous mining process for gently dipping medium-thick ore bodies. Background Technology

[0002] The mining methods for gently dipping, medium-thick ore bodies in metal mines mainly include room-and-pillar mining, sublevel open-stope filling, and upward layered filling.

[0003] Room and pillar mining, which supports the roof by leaving regular pillars, is suitable for ore bodies with good rock stability, but it has low mechanization, high labor intensity, low production capacity, and high pillar resource loss. Subgrade stope backfilling has a larger production capacity, but it has high dilution loss, large blasting disturbance, and long exposure time of the goaf, which affects the stability of the surrounding rock in the stope. It is suitable for rock conditions with moderate to high stability. Upward layered backfilling has good safety and strong applicability, and can be flexibly adjusted according to the occurrence of the ore body. However, it has a large amount of mining and cutting work, low production capacity, and high mining cost. It is suitable for mines with high ore grade. Summary of the Invention

[0004] The purpose of this invention is to propose a continuous pull-type mining process for gently inclined medium-thick ore bodies, which can improve the level of mechanized mining, shorten the mining process, achieve continuous ore production, reduce underground personnel, and improve labor efficiency and production capacity.

[0005] This application provides a continuous pull-out mining process for gently dipping, medium-thick ore bodies, employing the following technical solution:

[0006] A continuous pull-out mining technique for gently dipping, medium-thick ore bodies includes the following steps:

[0007] S1, the division of mining units, first divides the panel area, then divides the panel area into layers, and arranges the mining area within the layer;

[0008] S2, arrange the mining preparation and cutting works, arrange the main haulage roadway, haulage channel, inclined ramp, haulage downhill, filling return airway, and return air channel in the footwall of the ore body, excavate the drainage channel from the haulage channel, excavate the filling channel from the return air channel, excavate the return air uphill along the footwall of the ore body from the haulage channel and connect the return air channel, excavate the ore extraction channel and ore extraction roadway along the channel from the inclined ramp / haulage downhill in sequence, and connect the return air uphill;

[0009] S3, layered mining, from the ore exit roadway along the vein to the mining area, until the boundary of the panel;

[0010] S31. Ore extraction and discharge: Ore is extracted by impact or cutting rock-breaking equipment and advanced to the boundary of the mining area; the ore is then transported through the vein extraction roadway, the extraction through the vein, and the transport downhill to the main transport roadway, and then hoisted to the surface;

[0011] S32, Ventilation, backfilling and drainage; mining every three stops, advancing in cycles, repeating the previous steps until the entire stratum is mined;

[0012] S4, the direction of layered mining advance is perpendicular to the dip line of the ore body, from bottom to top, until the mining of the entire panel is completed.

[0013] Optionally, in step S1: the ore body is divided into panels along the strike of the ore body, pillars are left between the panels, the panels are divided into layers perpendicular to the dip line of the ore body, and mining areas are arranged along the dip line within each layer.

[0014] Optionally, in step S1, the panel length is 500m~1000m, the height is 50m, the pillar width is 20m~30m; the layer thickness is 4m~5m, and the number of layers is 3~4; the stope length is 100m~200m, the width is 4m~6m, and the height is the layer thickness.

[0015] Optionally, in step S2, the transport channel, return air channel, and return air uphill are arranged at the position of the pillar.

[0016] Optionally, in step S2, the transport channel, return air channel, and return air uphill are arranged at the position of the pillar.

[0017] Optionally, in step S32, the ventilation involves fresh air being transported to the longwall face via the main transport roadway, ramp, ore outlet channel, and ore outlet roadway along the channel, while dust is discharged via the return air uphill, return air channel, and filling return airway.

[0018] Optionally, in step S32, the filling involves arranging filling retaining walls at both ends of the stope, laying filling pipes, and transporting the filling material to the goaf via the filling return airway, return air through the return air inlet, return air uphill, ore outlet through the ore outlet, and along the ore outlet roadway to complete the filling operation. The 28-day strength of the filling material is 2MPa~3MPa.

[0019] Optionally, in step S32, the drainage, filling seepage water and stope inflow water are discharged into the main transport roadway via the ore outlet roadway, ore outlet through the ore outlet, and transport downhill, and then transported to the mine water tank.

[0020] In summary, this application includes the following beneficial technical effects:

[0021] As can be seen from the above, the pull-type continuous mining technology and its layered mining method for gently dipping medium-thick ore bodies provided in this application, through modular division of mining units, optimization of mining preparation engineering layout, and adoption of pull-type continuous mining technology, realizes the coordinated operation of mechanized continuous mining and timely filling of goaf, effectively solving the problems of low resource recovery rate, poor stope stability, and limited production efficiency of traditional methods, and has the advantages of improving mining efficiency, enhancing stope stability, and optimizing resource recovery rate. Attached Figure Description

[0022] Figure 1 This is a front view schematic diagram of the recovery method of the present invention;

[0023] Figure 2 This is a side view schematic diagram of the recovery method of the present invention;

[0024] Figure 3 This is a top view schematic diagram of the mining method of the present invention.

[0025] Explanation of reference numerals in the attached figures:

[0026] 1. Transport main roadway; 2. Drainage roadway; 3. Transport through roadway; 4. Backfill return airway; 5. Backfill roadway; 6. Return air through roadway; 7. Return air uphill roadway; 8. Transport downhill roadway; 9. Inclined ramp; 10. Ore extraction roadway along the vein; 11. Ore extraction through roadway; 12. Pillar; 13. Stope; 14. Backfill body. Detailed Implementation

[0027] The following is in conjunction with the appendix Figure 1-3 This application will be described in further detail.

[0028] In existing technologies, mining methods for gently dipping, medium-thick ore bodies in metal mines suffer from drawbacks such as low mechanization, high pillar resource loss, poor goaf stability, and large mining and cutting workloads. The room-and-pillar method requires leaving numerous permanent pillars, leading to resource waste; the sublevel stope method suffers from significant blasting disturbance and long stope exposure time; and the upward stratification method faces bottlenecks such as high mining costs and insufficient production capacity. In one mine, when the mining depth reached 500 meters, traditional methods encountered technical challenges such as frequent roof collapses, low ore transportation efficiency, and disrupted ventilation systems.

[0029] To address the aforementioned issues, the research team discovered systemic flaws in the unit division and engineering layout of existing mining processes. By analyzing the occurrence of the ore body and the stress distribution patterns of the strata, they proposed combining panel-level stratification with pull-back mining to construct a continuously advancing three-dimensional mining system. The key breakthrough lies in adopting a unit division method perpendicular to the ore body strike, coupled with a multi-channel transportation network and a backfilling and ventilation system, to achieve continuous operation with a balance between mining and backfilling.

[0030] Therefore, this application proposes a continuous mining process including the division of mining units, engineering layout, and layered mining. First, the mining panel is divided along the strike of the ore body, and pillars are left. Within the panel, layers are divided perpendicular to the dip line of the ore body, and stopes are arranged along the dip line within each layer. Then, a three-dimensional roadway network, including haulage mains, ramps, and backfilling return airways, is constructed in the footwall of the ore body. Pull-type mining is carried out through the ore extraction roadways along the vein. During layered mining, mechanical rock-breaking equipment is used to extract the ore. The ore is transferred through a multi-stage transportation system, and backfilling operations are carried out simultaneously at intervals of three miners per day, ultimately forming an advance direction perpendicular to the dip line of the ore body.

[0031] The division of mining units refers to establishing a three-level mining structure based on the spatial morphology of the ore body. Specifically, geological modeling and numerical simulation can be used to determine the optimal division parameters, achieving spatial decoupling of mining units through a progressive division of panel-layer-stope. The arrangement of pre-mining cutting works refers to constructing a three-dimensional transportation and ventilation system. Specifically, this can be achieved by centrally arranging the main transport roadways in the footwall and setting up cross-vein roadways at the pillar locations, forming a two-way channel for ore transportation and air circulation. The direction of layered mining advance refers to the advancement of the working face along the dip line perpendicular to the ore body. Specifically, a retreating mining sequence can be adopted, forming a pulling working face by advancing bidirectionally along the vein's ore exit roadway.

[0032] Specifically, the mining operation first uses a three-dimensional geological model to determine the panel boundaries, and then constructs a main transportation network consisting of haulage roadways and inclined ramps under the protection of pillars. The longwall face unfolds along the dip direction of the ore body, advancing simultaneously from the vein exit roadway to both sides. Ore produced by continuous cutting equipment is directly transported to the surface via a multi-stage transfer system. The goaf is filled in stages, with the filling material and retained pillars forming a support system. The ventilation system promptly removes dust from the working face through a dedicated return air channel. The entire mining process forms a closed-loop flow of "division-tunneling-mining-filling," achieving coordinated control of continuous ore body mining and dynamic goaf management.

[0033] Through the above technical solutions, this application achieves an organic combination of mechanized continuous mining and dynamic backfilling of goaf areas. The three-dimensional layout of the ore transportation system and ventilation and backfilling channels effectively solves the ventilation and dust removal problems in deep mining, and the pull-type longwall mining process increases the working face advancement efficiency by more than 2 times. The collaborative support mechanism of pillars and backfilling bodies controls the exposed roof area to within 200 square meters, significantly improving the safety of stope operations. The staged backfilling operation shortens the mining and backfilling cycle to 7 days, ensuring the continuity of mining operations.

[0034] This application further proposes that in step S1, panels are divided along the strike of the ore body, pillars are left between panels, and layers are divided within the panels perpendicular to the dip line of the ore body, with mining areas arranged along the dip line within each layer.

[0035] Dividing the mining area along the strike of the ore body refers to dividing the area according to the direction of the ore body's extension. Specifically, geological exploration data can be used to determine the strike axis of the ore body, and continuous mining units can be divided along this axis. This method matches the natural morphology of the ore body and avoids ineffective mining areas. A pillar refers to a pre-reserved support structure between adjacent mining areas. Specifically, continuous or intermittent rock masses can be left at the mining boundary to maintain roof stability and reduce the risk of surrounding rock deformation. Dividing the mining layers vertically along the dip line of the ore body refers to dividing the mining layers according to the vertical lines perpendicular to the dip direction of the ore body. Specifically, 3D modeling technology can be used to determine the layer cutting surfaces, ensuring that the layer interfaces are orthogonal to the dip direction of the ore body, facilitating control of the mining sequence. Arranging the mining area along the dip line refers to setting up mining units within each layer according to the dip direction of the ore body. Specifically, the long axis of the mining area can be adjusted according to the dip angle of the ore body, making the mining area strike parallel to the dip line of the ore body, thus adapting to the morphological characteristics of the ore body.

[0036] Specifically, the strike axis of the ore body is used as the benchmark for panel division. Adjacent panels are separated by pillars, and the panel itself is divided into multiple layers perpendicular to the dip line of the ore body. Within each layer, stopes are continuously arranged along the dip line of the ore body, forming mining units that match the ore body's occurrence. During mining, pillars provide roof support, the layer interfaces control the direction of mining advance, and the stope layout minimizes ore residue.

[0037] Through the above technical solutions, this application reduces the loss of pillar resources while ensuring the stability of the roof, reduces the amount of mining and cutting work by optimizing the layered cutting and stope layout, and utilizes the occurrence characteristics of the ore body to achieve spatial matching between the mining unit and geological conditions, thereby improving the mining efficiency and reducing the ore dilution rate.

[0038] This application further proposes that in step S1, the panel length is 500m~1000m, the height is 50m, the pillar width is 20m~30m, the layer thickness is 4m~5m, the number of layers is 3~4, the stope length is 100m~200m, the width is 4m~6m, and the height is the layer thickness.

[0039] The panel length refers to the continuous mining area defined along the strike of the ore body, which can be achieved through segmented development or roadway excavation. Mining efficiency and roof pressure are balanced by controlling the size of the mining units. The panel height refers to the vertical mining range of the ore body, determined by limiting the mining depth to match equipment operating capabilities. The pillar width refers to the size of the isolation zone between adjacent panels, determined by rock mechanics calculations to meet support strength requirements. The layer thickness refers to the vertical advance of a single mining operation, determined by matching the operating parameters of the rock-breaking equipment. The stope length refers to a single working unit arranged along the strike of the ore body, maintaining the self-stabilizing capacity of the surrounding rock by controlling the exposed area. The stope width refers to the span of the working face perpendicular to the strike of the ore body, determined by matching the dimensions of the transportation equipment.

[0040] Specifically, the mining panel is divided along the strike of the ore body by a predetermined length to form continuous mining units, with pillars retained between adjacent panels to support the roof. Vertically, the panel is divided into multiple layers, each layer's thickness matching the cutting depth of the rock-breaking equipment. The stopes are arranged along the dip direction of the ore body. The stope length is determined based on the continuity of the ore body and the equipment's advancing capacity, while the width matches the layout requirements of the ore transport channels. By controlling the correlation between layer thickness and stope height, the amount of ore extracted in a single operation is adapted to the handling capacity of the transport system, enabling continuous ore extraction.

[0041] Through the above technical solutions, this application realizes continuous and efficient operation of mechanized equipment. By matching the layer thickness design with the equipment performance, the amount of secondary crushing operations is reduced. The reasonable planning of the stope size reduces the roadway excavation ratio. The scientific setting of the pillar width ensures the stability of the stope while improving the ore recovery rate. The control of the number of layers keeps the filling operation synchronized with the recovery progress, avoiding safety hazards caused by long-term exposure of the goaf.

[0042] This application further proposes that in step S2, the transport channel, return air channel, and return air uphill are arranged at the pillar location.

[0043] This application further proposes ventilation in step S32, in which fresh air is transported to the longwall face via the transport roadway, ramp, ore outlet channel, and ore outlet roadway along the channel, while dust is discharged via the return air uphill, return air channel, and filling return airway.

[0044] Fresh airflow refers to the flow of uncontaminated air with adequate oxygen content. This can be achieved by creating a negative pressure environment driven by the main ventilation fan to maintain the breathing needs of personnel at the work site and dilute harmful gases. Dust refers to micron-sized particles generated during ore crushing. This can be treated using a wet dust collector in conjunction with a negative pressure suction system to prevent its spread within the roadway. The return air incline refers to an inclined passage connecting different horizontal roadways. This can be designed as a rectangular cross-section structure with protective netting and guide plates to establish a dedicated dust emission path. The filling return airway is a horizontal roadway that serves both as a conveyor for filling materials and a vent for waste air. This function can be switched using isolation dampers to ensure the stability of the ventilation system.

[0045] Specifically, during the layered mining process, the main ventilation fan establishes a negative pressure environment at the entrance of the transport roadway, prompting fresh air to flow downwards along the inclined ramp. After entering the ore extraction roadway via the ore extraction channel, the air forms a transverse airflow that runs through the mining face, effectively dispersing dust generated by blasting. Under the influence of negative pressure, the dust-laden airflow migrates upwards along the return air incline and enters the filling return airway for centralized treatment via the return air channel. This ventilation path achieves physical isolation between polluted and fresh air by constructing an independent upward air duct, avoiding recirculation pollution.

[0046] Through the above technical solution, this application effectively solves the problems of chaotic ventilation paths and serious dust accumulation in traditional mining processes, achieves continuous improvement in air quality at the mining face, reduces occupational health risks, and avoids the increased costs associated with adding temporary ventilation facilities.

[0047] This application further proposes to arrange filling retaining walls at both ends of the stope, lay filling pipes, and transport the filling material to the goaf through the filling return airway, return air through the return air incline, return air uphill, ore outlet through the ore outlet, and along the ore outlet roadway to complete the filling operation. The 28-day strength of the filling material is 2MPa~3MPa.

[0048] The backfill retaining wall refers to the closed structure set at the end of the stope, which can be constructed using cast concrete or precast slabs to prevent backfill material from overflowing and maintain the boundary shape of the goaf. The backfill pipe refers to the pipeline system for transporting backfill material, which can be connected using wear-resistant steel pipes or flexible hoses and laid on the roof or sidewalls of the roadway for directional transport. The 28-day strength of the backfill body refers to the compressive strength range of the backfill material after 28 days of curing. This can be achieved by adjusting the ratio of the cementing material, for example, using a cemented backfill material with a cement-sand ratio of 1:6 to 1:8. This strength range can balance the load-bearing capacity of the backfill body with cost control requirements.

[0049] Specifically, the backfilling operation utilizes the existing roadway network to plan the transport path. After preparation at the surface, the backfill material enters the return airway via the backfill return airway, then ascends through the return airway to the ore extraction airway, and finally flows into the goaf via the ore extraction airway along the vein. This path utilizes the ventilation and transport channels formed during the mining phase, avoiding the need for separate backfilling shafts. During the backfilling process, retaining walls prevent slurry leakage into the work area, while the backfill pipes laid along the roadways reduce pipeline maintenance workload. The support structure formed after the backfill solidifies effectively controls roof subsidence; its strength range meets the stability requirements of layered mining while avoiding material waste due to excessive strength.

[0050] Through the above technical solution, this application solves the problems of large workload, high cost and inaccurate strength control in traditional filling processes, realizes efficient reuse of filling paths and quantitative control of material properties, thereby improving the economy and safety of filling operations.

[0051] This application further proposes the drainage in step S32, in which the filling seepage water and the mining area inflow water are discharged into the transport roadway via the ore outlet roadway, the ore outlet through the ore outlet, and the transport downhill roadway, and then transported to the mine water tank.

[0052] Among these, "filling seepage" refers to excess water released during the solidification process of the filling material. This can be achieved by setting a permeable layer or diversion channel within the filling body to prevent water retention and its impact on strength. "Mining inflow" refers to water accumulation during mining caused by geological structures or groundwater seepage. This can be achieved by pre-burying drainage pipes or setting up sump pits to prevent flooding of the mining face. "Ore transport roadway along the vein" refers to ore transport roadways arranged along the ore body's strike. These can be formed by tunneling machines or blasting excavation and simultaneously serve as drainage channels, reducing additional engineering investment. "Transport downhill" refers to inclined passageways connecting transport roadways at different levels. These can be implemented using stepped or spiral structures to allow water to flow by gravity to the main transport roadway.

[0053] Specifically, during the layered mining process, the oozing water generated from backfilling operations and the seepage water from within the stope first converge at the bottom of the ore extraction roadway along the vein, and then enter the haulage downhill through the ore extraction cross-section. The water flows downwards in the haulage downhill under gravity, eventually flowing into the centralized drainage system of the main haulage roadway, and is then pumped or gravity-fed to the mine's water sump for sedimentation treatment. In this process, the ore extraction roadway along the vein, the ore extraction cross-section, and the haulage downhill are reused as drainage channels, eliminating the need for separate drainage roadways.

[0054] Through the above technical solution, this application realizes the rapid and centralized discharge of backfilling water and mining water, effectively preventing the problem of roof stability decline caused by mining water accumulation. At the same time, it reduces the construction cost of the drainage system by utilizing existing transport roadways, and improves the continuity and safety of mine production.

[0055] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A continuous pull-out mining technique for gently dipping, medium-thick ore bodies, characterized in that... Includes the following steps: S1, the division of mining units, first divides the panel area, then divides the panel area into layers, and arranges the mining area within the layer; S2, arrange the mining preparation and cutting works, arrange the main haulage roadway, haulage channel, inclined ramp, haulage downhill, filling return airway, and return air channel in the footwall of the ore body, excavate the drainage channel from the haulage channel, excavate the filling channel from the return air channel, excavate the return air uphill along the footwall of the ore body from the haulage channel and connect the return air channel, excavate the ore extraction channel and ore extraction roadway along the channel from the inclined ramp / haulage downhill in sequence, and connect the return air uphill; S3, layered mining, from the ore exit roadway along the vein to the mining area, until the boundary of the panel; S31. Ore extraction and discharge: Ore is extracted by impact or cutting rock-breaking equipment and advanced to the boundary of the mining area; the ore is then transported through the vein extraction roadway, the extraction through the vein, and the transport downhill to the main transport roadway, and then hoisted to the surface; S32, Ventilation, backfilling and drainage; mining every three stops, advancing in cycles, repeating the previous steps until the entire stratum is mined; S4, the direction of layered mining advance is perpendicular to the dip line of the ore body, from bottom to top, until the mining of the entire panel is completed.

2. The continuous pull-out mining process for gently dipping, medium-thick ore bodies according to claim 1, characterized in that: In step S1: the ore body is divided into panels along its strike, pillars are left between the panels, the panels are divided into layers perpendicular to the dip line of the ore body, and mining areas are arranged along the dip line within each layer.

3. The continuous pull-out mining process for gently dipping, medium-thick ore bodies according to claim 2, characterized in that: In step S1, the panel length is 500m~1000m, the height is 50m, the pillar width is 20m~30m, the layer thickness is 4m~5m, and the number of layers is 3~4; the stope length is 100m~200m, the width is 4m~6m, and the height is the layer thickness.

4. The continuous pull-out mining process for gently dipping, medium-thick ore bodies according to claim 3, characterized in that: In step S2, the transport channel, return air channel, and return air uphill are arranged at the position of the pillar.

5. The continuous pull-out mining process for gently dipping, medium-thick ore bodies according to claim 4, characterized in that: In step S2, the transport channel, return air channel, and return air uphill are arranged at the position of the pillar.

6. The continuous pull-out mining process for gently dipping, medium-thick ore bodies according to claim 5, characterized in that: In step S32, ventilation involves fresh air being transported to the longwall face via the main transport roadway, inclined ramp, ore outlet channel, and ore outlet roadway along the channel, while dust is discharged via the return air uphill, return air channel, and filling return airway.

7. The continuous pull-out mining process for gently dipping, medium-thick ore bodies according to claim 6, characterized in that: In step S32, the filling process involves setting up filling retaining walls at both ends of the stope, laying filling pipes, and transporting the filling material to the goaf via the filling return airway, return air through the return air incline, return air uphill, ore outlet through the ore outlet, and along the ore outlet roadway to complete the filling operation. The 28-day strength of the filling material is 2MPa~3MPa.

8. The continuous pull-out mining process for gently dipping, medium-thick ore bodies according to claim 7, characterized in that: In step S32, the drainage, filling seepage water and mining water flow through the ore outlet roadway, ore outlet through the ore outlet, and transport downhill are discharged to the transport roadway and then transported to the mine water tank.

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