A method for recovering isolated pillars containing ridge residues

Abstract

The invention discloses a method for recovering isolated ore pillars containing ridge residues, comprising a ground control system, a distance measurement and positioning system, a material level monitoring system, and a vehicle-mounted control system. The distance measurement and positioning system, the material level monitoring system, and the vehicle-mounted control system are all connected with the ground control system by signal. The distance measurement and positioning system is installed at one end of a belt conveyor to detect the position of a discharge trolley. The material level monitoring system comprises material level sensors installed in each silo. The vehicle-mounted control system is installed on the discharge trolley to control the discharge trolley to move along the belt conveyor. The vehicle-mounted control system is connected to the ground control system by wireless communication. The invention realizes remote control and centralization. Both a workshop and a factory centralized control room can be remotely controlled to realize automatic material distribution, and can prevent material blockage and empty silo accidents.

Description

Technical Field

[0001] The invention relates to the technical field of isolation pillar recovery technology, in particular to a recovery method for isolation pillars containing ridge residues. Background Art

[0002] With the rapid development of my country's economy, the consumption of mineral resources is becoming increasingly serious. More and more mining companies are facing the severe situation of insufficient mineral resource reserves and declining annual production capacity. In order to alleviate the shortage of mineral resources and extend the service life of mines, many underground production mines have gradually put the mining of residual ores such as isolation pillars on the agenda, and analyzed and studied the feasibility of their recovery. Usually, most of these isolation pillars are top and bottom pillars left behind by early mining designs. If such ores cannot be effectively recovered, it will inevitably cause a waste of mineral resources and reduce the service life of mines; isolation pillars are an important legacy in the mining process of mine resources. Once the mine includes isolation pillars in the mining object, the mining difficulty it faces is self-evident. How to safely, reasonably and effectively recover the remaining isolation pillars on the basis of ensuring the safety and stability of the mining site is an urgent problem to be solved.

[0003] In order to solve the technical difficulties in the recovery of isolation pillars and ensure that the mine maintains a reasonable production capacity balance, the present invention aims at the problems of large recovery engineering volume, high cost, low recovery rate and long recovery cycle in the prior art, and designs a method for recovering isolation pillars containing ridge residues with short preparation time, less excavation engineering and high recovery rate, which has far-reaching significance for achieving a smooth and balanced transition and sustainable development in the later stage of the mine. Summary of the invention

[0004] The purpose of the present invention is to solve the technical problem of mining isolation pillars and peach-shaped pillars with ridge residues, and provide a method for mining isolation pillars containing ridge residues. Through reasonable process parameter design, reasonable arrangement of cutting shafts and layering heights, and reserved ore in the mining area, safe and efficient mining of isolation pillars and residual ridge residues above them can be achieved. The method coordinates the contradiction between mining efficiency and ore recovery rate. The method has short preparation time, small excavation engineering volume, high mining rate, and low loss and depletion rate.

[0005] In order to achieve the above object, the present invention adopts the following technical solution: a method for recovering isolated pillars containing ridge residues, comprising the following steps:

[0006] 1) Mining and cutting project layout: Make full use of the existing development tunnels, segmented transportation tunnels, segmented rock drilling tunnels and segmented connecting tunnels, chute, stope ramps and segmented vein connecting tunnels in the mining area, and add rock drilling tunnels in combination with the need for isolation pillar mining, so that the mining workload is small and the preparation time for mining is short;

[0007] 2) Stope layout and parameter selection: The height of the isolation pillar is 12m. The upper part of the top pillar is a caving stope with residual ridges. The isolation pillar is mined in layers, with the upper layer being 8m and the lower layer being 4m. The lower layer approach is set as an isosceles trapezoidal approach that alternates between positive and negative. The centerline of the positive trapezoidal approach faces the mining approach of the upper caving stope, and the centerline of the negative trapezoidal approach faces the residual peach-shaped pillar ridge of the upper caving stope.

[0008] 3) Blasting mining: The upper layer is mined by caving method, and the lower layer is mined by access road. The access road of the lower layer is "mined every three", and the trapezoidal access road is mined first, and backfilled in time after mining. After the backfill reaches the safety strength, the inverted trapezoidal access road is mined, and no backfilling is performed after mining. It serves as the working platform, blasting compensation space and mine access road for the upper layer of the caving method;

[0009] 4) Approach filling: The positive trapezoidal approach needs to be filled after mining. Before filling, prefabricated arc skeletons, fixed anchors and metal mesh can be arranged in the goaf. Or, by adjusting the parameters of the positive and negative trapezoidal approach, a certain thickness of ore body can be reserved outside the filling body as a wall pillar to protect the filling body, thereby improving the stability and safety of the mining site.

[0010] Among them, the isolation pillar is used to isolate the lower middle section filling stope from the upper middle section caving stope, and the peach-shaped pillar is the ridge remnant between the last subdivision access roads of the upper middle section caving method. The height of the isolation pillar is 9~15m, divided into two layers; the distance between the mining access roads in the upper subdivision caving stope is 10~15m.

[0011] In the step 2), the long side dimension of the trapezoidal approach is 6-8m, the short side dimension is 4-7m, the trapezoidal height is 3-5m, the base angle of the isosceles trapezoidal approach is 60°-80°, and the top angle is 100°-120°.

[0012] In the step 3), if the method of first excavating and then expanding the blasting to form a trapezoidal approach is adopted, the size of the excavation section can be designed to be a (3~5)m×(3~5)m specification section.

[0013] Furthermore, in step 4), the filling strength of the positive trapezoidal approach is selected according to the actual mining ground pressure and the actual needs of safe production. After the inverted trapezoidal approach is excavated, considering the top connection of the filling stope in the lower middle section of the approach, the compressive strength and the working height required for the blasting upper layer, a layer of 0.5-1.5m of waste rock cemented filling body can be appropriately poured in the approach. On the one hand, the waste rock generated during production is consumed, and only a small amount of mortar is needed for filling. On the other hand, a working platform with a suitable reserved height, a bottom plate strength that meets the operation of mining equipment, and a flat bottom surface can be constructed.

[0014] In step 4), the arc-shaped frame is a double-layer frame, and the metal mesh and the arc-shaped frame are adjacent to each other through metal anchor rods to form a force-bearing whole. The metal frame and the anchor rods are both made of ribbed steel bars, and the metal anchor rods are arranged at 1 / 2 of each side of the inverted trapezoid and at the intersection of the two sides, and the metal anchor rods are welded to the arc-shaped frame, and cement filling is performed after the arrangement is completed.

[0015] Furthermore, in the step 4), part of the ore is reserved to form wall pillars on both sides of the right trapezoidal filling body approach. By changing the top and bottom angles and the upper and lower lengths of the right and inverted trapezoids, wall pillars with rectangular, wedge-shaped or triangular cross-sections can be left on both sides of the filling body approach. According to the mechanical parameter performance of the filling body and the mining ground pressure, a reasonable support method, internal skeleton layout of the filling body and reserved wall pillar thickness are selected.

[0016] Compared with the prior art, the present invention has the following advantages: compared with the conventional bottomless pillar caving method for recovering transition segments, the upper residual peach-shaped pillars and part of the ore in the segment can be recovered, but new residual peach-shaped pillars will be formed in the subsequent segment, and the resource recovery rate of the isolation pillars is low; compared with the conventional approach-type filling recovery, because the upper part of the isolation pillars is the residual ridge residue and loose waste rock, it is necessary to reserve a certain thickness of isolation pillars, the resource recovery rate is low, and the excavation workload is large; compared with the approach-caving combined stratified mining method, the number of excavation approaches is large, the rock drilling workload is large, the mining cost is high, and the preparation time is long; the present invention combines the trapezoidal approach cementation filling and the caving method, which can effectively coordinate the contradiction between the recovery cost and the loss and depletion rate, and through the reasonable design of the trapezoidal approach mining field parameters, it can effectively reduce the loss and depletion of ore, and safely and efficiently recover the isolation pillars and the residual ore on the ridge, which is beneficial to the production capacity balance and sustainable development of the mine. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of mining the isolation pillar and the peach-shaped pillar above it provided by an embodiment of the present invention;

[0018] Figure 2 for Figure 1 Schematic diagram of the structure along the Ⅰ-Ⅰ direction;

[0019] Figure 3 for Figure 1 Schematic diagram of the structure along the II-II direction;

[0020] Figure 4 It is a schematic diagram of the prefabricated skeleton and the ore structure of the retaining wall;

[0021] In the figure: 1. Backfill; 2. Loose surrounding rock; 3. Chute; 4. Mining site connecting tunnel; 5. Blast hole; 6. Transport tunnel; 7. Segmented transport tunnel; 8. Rock drilling approach; 9. Backfill; 10. Wall protection pillar; 11. Prefabricated skeleton; 12. Anchor rod. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0023] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0024] like Figure 1 , Figure 2 , Figure 3 The mining field structure parameters of this embodiment are as follows: the segmented height of the isolation pillar ore body is 12m, the upper and middle sections are caving mining fields and have been mined, the spacing between the caving mining roads is 10m, there are residual peach-shaped pillars between the roads, and the lower part of the isolation pillar is a filling mining field and has been filled.

[0025] The method for recovering isolated pillars containing ridge residues in this embodiment specifically comprises the following steps:

[0026] 1) Mining and cutting project layout: Make full use of the existing projects in the mining area to develop tunnels, segmented transportation tunnels, connecting tunnels and chute shafts, and increase rock drilling tunnels in combination with the need for isolation pillar mining;

[0027] 2) Stope layout and parameter selection: The height of the isolation pillar is 12m. The upper part of the top pillar is a cave-in stope with residual ridges. The 12m high isolation pillar is divided into two upper and lower layers of 8m and 4m. The lower layer is designed as a regular and inverted isosceles trapezoid arranged at intervals, with the long side of the trapezoid being 6m and the short side being 4m. The centerline of the regular trapezoid approach faces the mining approach of the upper cave-in stope, and the centerline of the inverted trapezoid approach faces the residual peach-shaped pillar ridge of the upper cave-in stope;

[0028] 3) Blasting mining: The upper layer is mined by caving, and the lower layer is mined by access. The access of the lower layer is "mined every three", and the trapezoidal access is mined first, and backfilled in time after mining. After the backfill reaches the safety strength, the inverted trapezoidal access is mined, and no backfilling is performed after mining. It serves as the working platform, blasting compensation space and mine access for the upper layer of the retreat caving mining;

[0029] 4) Approach filling: The trapezoidal approach needs to be filled after mining. Before filling, prefabricated arc skeletons, fixed anchor rods and metal mesh are arranged in the goaf. The arc skeleton is a double-layer skeleton, and the metal mesh and the arc skeleton are adjacent to each other through metal anchor rods to form a force-bearing whole. The metal skeleton and anchor rods are made of ribbed steel bars. Metal anchor rods are arranged at 1 / 2 of each side of the inverted trapezoid and at the intersection of the two sides, and the metal anchor rods are welded to the arc skeleton. After the arrangement is completed, cementation filling is carried out.

[0030] The filling strength of the positive trapezoidal approach is filled with filling slurry with a suitable lime-sand ratio according to the actual ground pressure of the mining and the actual needs of safe production. After the inverted trapezoidal approach is excavated, considering the top connection degree, compressive strength and layer height of the filling body in the lower middle section of the approach, a layer of waste rock cementing filling body of about 1m can be appropriately poured in the approach. On the one hand, it consumes the waste rock generated during production and only requires a small amount of mortar filling. On the other hand, it builds a working platform with appropriate reserved height, appropriate bottom plate strength and flat bottom surface.

[0031] By adjusting the parameters of the forward and inverted trapezoidal approach, a certain thickness of ore can be reserved outside the filling body. The reserved ore forms wall pillars on both sides of the forward and inverted trapezoidal filling body approach to protect the filling body and improve the overall stability and safety of the mining site. By changing the top and bottom angles and the lengths of the upper and lower sides of the forward and inverted trapezoidal shape, wall pillars with rectangular, wedge-shaped or triangular cross-sections can be left on both sides of the filling body approach.

Claims

1. A method for recovering isolated pillars containing ridge residues, characterized in that: The upper part of the isolation pillar is the middle section of the caving mining method, and the upper caving stope has been mined, and there are ridge residues. The lower part of the isolation pillar is the middle section of the filling mining method, and the lower filling stope has been mined and filled. The mining method includes the following steps: 1) Mining and cutting project layout: Utilize the existing development tunnels, segmented transport tunnels, and chute, and design layered transport tunnels and connecting tunnels in combination with the needs of isolated pillar mining; 2) Stope layout and parameter selection: The height of the isolation pillar is H, the upper part of the top pillar is a caving stope with residual ridges, and the isolation pillar is mined in layers, with the upper layer being 2 / 3H and the lower layer being 1 / 3H. The lower layer approach is set as an isosceles trapezoidal approach that alternates between positive and negative. The centerline of the positive trapezoidal approach faces the mining approach of the upper caving stope, and the centerline of the negative trapezoidal approach faces the residual peach-shaped pillar ridge of the upper caving stope; 3) Blasting mining: The upper layer is mined by caving, and the lower layer is mined by access. The access of the lower layer is "mined every three", and the trapezoidal access is mined first, and backfilled in time after mining. After the backfill reaches the safety strength, the inverted trapezoidal access is mined, and no backfilling is done after mining. It serves as the working platform, blasting compensation space and mine access for the upper layer of the retreat caving mining; 4) Approach filling: The regular trapezoidal approach needs to be filled after mining. Before filling, prefabricated arc skeletons, fixed anchor rods and metal mesh are arranged in the goaf, or by adjusting the parameters of the regular trapezoidal approach and the inverted trapezoidal approach, a certain thickness of ore body is reserved outside the filling body as a wall pillar to protect the filling body, so as to improve the overall stability and safety of the mining site.

2. The method for recovering isolated pillars containing ridge residues according to claim 1, characterized in that: In the step 1), the existing development projects in the mining area are fully utilized to arrange the mining and cutting projects for isolating the pillars and the residual ore on the ridges, and the layered transportation tunnels and connecting tunnels for the residual ore recovery mining area are set up in combination with the segmented rock drilling tunnels, segmented connecting tunnels, mining area slope tunnels and segmented vein tunnels.

3. The method for recovering isolated pillars containing ridge residues according to claim 1, characterized in that: In the step 2), the height of the isolation pillar is 9-15m, which is divided into two layers; the distance between the mining access roads of the upper subgrade caving stope is 10-15m.

4. The method for recovering isolated pillars containing ridge residues according to claim 1, characterized in that: In the step 2), the long side of the trapezoidal approach is 6-8m, the short side is 4-7m, the angle between the hypotenuse and the long base of the regular trapezoidal approach is 60°-80°, and the angle between the hypotenuse and the short base of the inverted trapezoidal approach is 100°-120°.

5. The method for recovering isolated pillars containing ridge residues according to claim 1, characterized in that: In the step 3), the lower layer trapezoidal approach is mined, and according to the designed layering situation, a rock drill is used to drill rocks at one time and a horizontal hole blasting is used to excavate a regular trapezoidal approach, or a section with a size of (3~4)m×(3~4)m is first excavated, and after the excavation is completed, it is expanded from the inside to the outside to form a regular trapezoid with the designed parameters. After the regular trapezoidal approach is mined, it is filled in time, and after the strength of the filling body reaches the safety standard, the inverted trapezoidal approach is mined; the inverted trapezoidal approach directly excavates an approach with a size of 4m×4m, and then a cutting groove is excavated to create a free surface and compensation space for collapse mining, and upward fan-shaped blastholes are arranged in the inverted trapezoidal approach. The peach-shaped ore pillars remaining on the upper segment ridge, the upper layer isolation ore pillars and the ore within the range of the inverted trapezoidal approach are blasted out at one time by row blasting, and the ore is stopped according to the actual cut-off grade of the mine.

6. The method for recovering isolated pillars containing ridge residues according to claim 5, characterized in that: The inverted trapezoidal approach determines whether filling is required based on the layer height and the condition of the lower filling body. If the layer height is greater than 4m or the strength of the lower filling body of the approach is low, the filling thickness should be appropriate so that the working space height and the working platform strength meet the requirements for the operation of the rock drilling and blasting equipment.

7. The method for recovering isolated pillars containing ridge residues according to claim 1, characterized in that: In the step 4), before filling, an arc-shaped skeleton is placed in the trapezoidal goaf, a metal mesh is arranged at the boundary of the trapezoidal approach, and the metal mesh and the arc-shaped skeleton are connected as a whole with metal anchor rods to improve the strength of the filling body; or by adjusting the parameters of the trapezoidal approach and the inverted trapezoidal approach, a part of the ore is reserved between the trapezoidal approach and the inverted trapezoidal approach to cover the outer wall of the trapezoidal filling body to form a protective wall pillar, so as to further improve the stability and safety of the mining site.

8. The method for recovering isolated pillars containing ridge residues according to claim 7, characterized in that: The metal frame and anchor rods are both made of ribbed steel bars. The metal anchor rods are arranged at the 1 / 2 of each side of the inverted trapezoid and at the intersection of the two sides, and are welded to the arc-shaped frame. After the arrangement is completed, bonding and filling are carried out.

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