Safe and efficient mining method for ore bodies under large-area filling bodies

Abstract

The present invention provides a method for safe and efficient mining of ore bodies under large-area filling bodies, which first divides the middle section and then divides the mining field; each mining field is divided into three sections from bottom to top; then the mining and cutting engineering is arranged; then the two lower sections are mined by the empty field and subsequent filling mining method in the segmented rock drilling stage to maximize the production capacity of the mining field; then a reinforcement layer is set in the bottom structure of the upper middle section to ensure that the upper filling body will not collapse as a whole during the mining of the third segmented ore body; during the mining of the third segment, the entire mining field is mined using the same method. In the mining process, the present invention does not need to set a top column or only needs to set a top column with a very small thickness, has high mining efficiency, high ore recovery rate, low mining cost, and high safety, and solves the mining technical problem that the filling body is prone to collapse as a whole during the safe and efficient mining of ore bodies under large-area filling bodies; the economic and social benefits are significant, and it can be promoted and applied in mines of the same type, and has broad application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of mining, and in particular to a method for safely and efficiently mining an ore body under a large-area filling body. Background Art

[0002] For steeply inclined medium-thick or thick ore bodies with medium-stable or above rock conditions, the mining method of empty field followed by filling in the stage of segmented rock drilling is mostly used for mining. This mining method has the advantages of less mining engineering, large production capacity and low mining cost. At present, in order to speed up the pace of production and achieve full production and create benefits as early as possible, some mines have started normal mining construction in the shallow production middle section when the overall production system of the mine is initially formed and the deep development project has not yet been put in place, resulting in the mining sequence of the entire ore body being changed from top to bottom. Therefore, after the mining of the upper middle section is completed, the exposed area and vertical height of the goaf are large. After the mining is completed, it is impossible to adopt the treatment method of laying reinforcement first and then filling the goaf, resulting in the inability to ensure the strength of the filling body itself. The lower middle section is exposed under a large area of ​​filling body during the mining operation. When the mining height of the lower stope is close to the filling body position of the upper middle section, there is a risk of the upper filling body collapsing as a whole.

[0003] In order to reduce the safety risks in the mining process and ensure production safety, thicker top pillars are generally left in the lower middle section of the mining area to ensure that the upper filling body will not collapse, resulting in a large amount of ore that cannot be recovered in time, a low mining recovery rate, and a restriction on the sustainable and stable development of the mine. If the top pillar needs to be further recovered in the future, the only way to recover it is to use the approach method with small structural parameters. This method has the disadvantages of large mining engineering, small production capacity, high cost, complex procedures, and greater difficulty in safe production management. At the same time, due to the low cohesion and poor shear resistance of the filling body, there is still a risk of the upper filling body falling during the approach recovery process, which poses a great safety hazard. Once the above situation occurs, the entire approach mining area in the lower plate area of ​​the filling body will not be able to be recovered normally, resulting in the loss of ore resources, which will have an adverse impact on the stability of the mine's production capacity and production planning, and affect the development of the mine.

[0004] In view of this, it is necessary to design an improved method for safe and efficient mining of ore bodies under large-area filling bodies to solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a safe and efficient mining method for an ore body under a large-area filling body. Through a mining process of pre-reinforcement of a segmented rock drilling stage, followed by empty-field filling, and combined mining of segmented filling, each middle section is divided into three sections. First, the two lower sections are mined by a segmented rock drilling stage empty-field followed by filling mining method to maximize the production capacity of the mining area. Then, a reinforcement layer is set in the bottom structure of the upper middle section to ensure that the upper filling body will not collapse as a whole during the mining of the lower middle section ore body. There is no need to set a top column or only a top column with a very small thickness needs to be set. The mining efficiency is high, the ore recovery rate is high, the mining cost is low, and the safety is high.

[0006] To achieve the above-mentioned purpose, the present invention provides a method for safe and efficient mining of an ore body under a large-area filling body, comprising the following steps:

[0007] S1. Divide the ore body into several middle sections from top to bottom along the ore body trend; each middle section is divided into a first-step stope and a second-step stope at intervals perpendicular to the ore body trend without leaving any pillars; each stope is divided into three sections from bottom to top: the first section, the second section and the third section;

[0008] S2. Excavate an off-vein ramp on one side of the lower wall of the ore body; excavate an off-vein segmented transport lane outside each segment along the direction of the ore body, the off-vein ramp is connected to the off-vein segmented transport lane; excavate a segmented rock drilling lane along the lower wall of the ore body of each segment to the upper wall of the ore body through the off-vein segmented transport lane, and at the same time, excavate a mine-exiting vein to both sides of the segmented rock drilling lane every 6-8m in the first segmented rock drilling lane, the mine-exiting vein is connected to the segmented rock drilling lane of the first segment of the adjacent stope;

[0009] S3. Excavate cutting lanes and cutting shafts in the first segment near the upper wall of the ore body, blast into cutting grooves with the cutting shaft as the free surface, and then blast and mine with the cutting grooves as the free surface and compensation space, and simultaneously mine the first segment and the second segment from the upper wall of the ore body to the lower wall of the ore body, forming a "V"-shaped ore-receiving trench at the bottom of the first segment; and then fill the first segment and the second segment;

[0010] S4. construct a horizontal hole in the segmented rock drilling tunnel of the second-step stope of the first segment of the upper middle segment toward the adjacent first-step stope that has been excavated and filled, the horizontal hole penetrates the filling body of the first-step stope and extends to the triangular ore pillar of the second-step stope on the other side, and a reinforcement component is arranged in the horizontal hole and reinforced by grouting; the reinforcement component is one of an anchor cable, a steel bar or a threaded rod;

[0011] S5. Repeat the mining method of step S3 to mine the third segment and fill it;

[0012] S6. First mine the first-step stope of the same middle section, then mine the second-step stope, until the mining of the middle section is completed; mine the next middle section from top to bottom in sequence, until the mining of the ore body is completed.

[0013] As a further improvement of the present invention, in step S1, the height of the middle section is 40-60m; the widths of the first-step stope and the second-step stope are both 10-15m.

[0014] As a further improvement of the present invention, in step S4, the drilling diameter of the horizontal holes is 50-70 mm, the hole depth is 20-30 m, and the row spacing between adjacent horizontal holes is 1-2 m.

[0015] As a further improvement of the present invention, the horizontal hole is 3-5m away from the bottom plate of this section.

[0016] As a further improvement of the present invention, the mining process in step S3 and step S5 is specifically as follows: the mining process adopts a lateral caving process, and uses a drilling rig or a YGZ90 drilling rig to construct an upward fan-shaped hole in the segmented drilling tunnel. When caving, two detonating cord detonators are loaded into the bottom of the hole detonator for bottom hole detonation. The cutting well groove blasting hole next to the cutting skylight is first blasted to form a cutting groove, and then the cutting groove is used as a free surface and compensation space for segmented micro-difference blasting backward in sequence.

[0017] As a further improvement of the present invention, in step S4, a YGZ-90 drilling rig or a drilling rig is used to construct the horizontal hole.

[0018] As a further improvement of the present invention, the width of the stope is 12.5 m; the height of the middle section is 50 m.

[0019] As a further improvement of the present invention, the heights of the first section and the second section are both 17 m, and the height of the third section is 16 m.

[0020] As a further improvement of the present invention, a segmented micro-difference blasting process is used, blasting 2-3 rows at a time.

[0021] As a further improvement of the present invention, the collapsed ore is unloaded by a scraper; the scraper passes through an off-vein segmented transport tunnel, a two-step segmented rock drilling tunnel, and the ore is unloaded through the vein into the receiving cutting ditch.

[0022] The beneficial effects of the present invention are:

[0023] (1) The method for safe and efficient mining of ore bodies under large-area filling bodies provided by the present invention addresses the technical difficulty of achieving safe and efficient mining of ore bodies under large-area filling bodies. Through a mining process of pre-reinforced segmented rock drilling stage empty field followed by filling and segmented rock drilling stage empty field followed by filling, each middle section is divided into three sections. First, the segmented rock drilling stage empty field followed by filling mining method is used to mine the lower two sections, thereby maximizing the production capacity of the mining area. Then, in the segmented rock drilling tunnel of the upper middle section two-step mining area, the adjacent one-step mining area that has been excavated and completed the filling is mined. Horizontal holes are constructed in the first-step mining area and the second-step mining area adjacent to the first-step mining area. The horizontal holes finally formed penetrate the filling body of the first-step mining area and extend to the triangular ore pillars of the second-step mining areas on both sides. Long anchor cables, steel bars or threaded rods are laid throughout the horizontal holes and reinforced by grouting, so as to achieve the effect of reinforcing and supporting the large-area filling body on the upper part, ensuring that the upper filling body will not collapse as a whole during the mining of the lower and middle sections of the ore body. There is no need to set a top column or only a top column with a very small thickness needs to be set, which has high mining efficiency, high ore recovery rate, low mining cost and high safety.

[0024] (2) The present invention provides a safe and efficient mining method for ore bodies under large-area filling bodies. Compared with the segmented filling method, this mining method greatly improves the production capacity of the mining site, reduces the amount of mining engineering, and effectively reduces the thickness of the top pillar. It solves the mining technical problem of the filling body being prone to overall collapse during the safe and efficient mining of ore bodies under large-area filling bodies. It improves the resource recovery rate while ensuring safety and production capacity. It has significant economic and social benefits and can be promoted and applied in mines of the same type, with broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the mining arrangement along the ore body direction of the present invention.

[0026] Figure 2 for Figure 1 Schematic diagram of the structure of section II-II.

[0027] Figure 3 for Figure 1 Schematic diagram of the structure of section III-III.

[0028] Figure 4 for Figure 1 Schematic diagram of the structure of section IV-IV.

[0029] Figure 5 for Figure 1 Schematic diagram of the structure of the VV section.

[0030] Reference numerals

[0031] 1-first section; 2-second section; 3-third section; 4-lower wall of the ore body; 5-outer-vein ramp; 6-outer-vein segmented transport tunnel; 7-segmented rock drilling tunnel; 8-upper wall of the ore body; 9-mine through the vein; 10-filling body; 11-reinforcement assembly; 12-triangular ore pillar; 13-top pillar; 14-collapsed ore; 15-medium-deep hole blasthole; 16-through-vein transport tunnel. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the scheme of the present invention are shown in the drawings, while other details that are not closely related to the present invention are omitted.

[0034] In addition, it should be noted that the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0035] See also Figures 1 to 5 As shown, the present invention provides a method for safe and efficient mining of an ore body under a large-area filling body, comprising the following steps:

[0036] S1. Stope division:

[0037] Along the ore body strike (the ore body strike refers to Figure 1 The ore body is divided into several middle sections from top to bottom along the X-axis (in the direction extending to the left and right sides), and each middle section is divided into one-step stope and two-step stope at intervals perpendicular to the ore body trend (first the one-step stope is mined, and then the two-step stope is mined), without leaving any pillars; each stope is divided into three sections from bottom to top, which are respectively recorded as the first section 1, the second section 2 and the third section 3.

[0038] The middle section is 40-60m high, the width of the first-step stope and the second-step stope is 10-15m, and the section height is 15-17m. Preferably, the middle section is 50m high; the width of the first-step stope and the second-step stope is 12.5m; the height of the first section 1 and the second section 2 is 17m, and the height of the third section 1 is 16m.

[0039] S2. Mining and cutting engineering:

[0040] An off-vein ramp 5 is excavated on one side of the ore body footwall 4. An off-vein segmented transport tunnel 6 is excavated outside each segment along the ore body strike, and the off-vein ramp 5 is connected to the off-vein segmented transport tunnel 6. A segmented rock drilling tunnel 7 is excavated along the ore body footwall 4 of each segment toward the ore body upper wall 8 through the off-vein segmented transport tunnel 6, and the three segments are connected to each other through the off-vein ramp 5, the off-vein segmented transport tunnel 6 and the segmented rock drilling tunnel 7.

[0041] At the same time, in the segmented rock drilling tunnel 7 of the first segment 1, the ore veins 9 (i.e. Figure 3 The distance between adjacent ore-producing veins 9 on the same side is 6-8m), and the ore-producing veins 9 are connected with the segmented rock drilling tunnel 7 of the first section 1 of the adjacent mining area (the segmented rock drilling tunnel 7 of the first section 1 of the adjacent mining area is used as a transportation passage, so it can be recorded as a vein transportation tunnel 16), forming a channel convenient for transporting ore.

[0042] Since the first-step stope is mined first and then the second-step stope is mined, the mining and cutting project can be carried out in the first-step stope of the same middle section first, and then the mining and cutting project can be carried out in the second-step stope after the mining of the first-step stope is completed. Alternatively, the mining and cutting projects of the first-step stope and the second-step stope of the same middle section can be completed at the same time, and then mining can be carried out. Alternatively, the mining and cutting projects of multiple middle sections can be completed together. The specific mining and cutting project can be freely set according to the actual situation. In order to facilitate mining, it is also possible to selectively carry out the excavation of certain tunnels of the second-step stope first, such as the segmented rock drilling tunnel 7 of the first segment 1 of the second-step stope.

[0043] S3. Mining of the first and second middle sections:

[0044] In the first section 1, a cutting tunnel and a cutting shaft are excavated near the upper wall 8 of the ore body or in the middle of a first-step stope. A cutting groove is blasted with the cutting shaft as the free surface, and then the cutting groove is used as the free surface and compensation space for blasting and mining. The backward mining method is adopted to mine from the upper wall 8 of the ore body to the lower wall 4 of the ore body. The mining height is the total height of the first section 1 and the second section 2, that is, the first section 1 and the second section 2 are mined at the same time.

[0045] Specifically, a rock drilling rig or YGZ90 drilling rig is used to construct upward fan-shaped holes, i.e., medium-deep hole blasting holes 15, in the segmented rock drilling tunnel 7; a cutting groove is blasted with the cutting skylight as the free surface, and then the cutting groove is used as the free surface and compensation space for blasting and mining. The mining process adopts the lateral caving process. When caving, two detonating cord detonators are loaded into the hole bottom detonator for hole bottom detonation. First, the cutting shaft groove blasting holes next to the cutting skylight are blasted to form a cutting groove, and then the cutting groove is used as the free surface and compensation space for segmented micro-difference blasting backward in sequence, blasting 2-3 rows at a time. After the mining is completed, a "V"-shaped receiving ore trench is formed at the bottom of the first segment 1, that is, triangular ore pillars are formed on both sides. The existence of the triangular ore pillars makes it easier for the blasted ore to fall. There is no need to set a "V"-shaped receiving ore trench at the bottom of the second segment 2.

[0046] The collapsed ore 14 is unloaded by a scraper; the scraper passes through the off-vein segmented transport tunnel 6, the through-vein transport tunnel 16, the two-step segmented rock drilling tunnel 7 and the ore-exiting through-vein 9 into the receiving cutting for unloading.

[0047] The first section 1 and the second section 2 are then filled.

[0048] S4. Pre-reinforcement process:

[0049] In the second step stope of the first subsection 1 of the upper middle section (such as Figure 1 As shown, in the segmented rock drilling tunnel 7 of the second-step stope (on both sides of the first-step stope directly above the middle section), horizontal holes are constructed in the adjacent first-step stope that has been excavated and completed and the second-step stope adjacent to the first-step stope. The final horizontal hole passes through the filling body 10 of the first-step stope and extends to the triangular ore pillars 12 of the second-step stopes on both sides. The reinforcement component 11 is laid in the entire length of the horizontal hole and reinforced by grouting, so as to achieve the effect of reinforcing and supporting the large-area filling body on the upper part, and ensure that the upper filling body will not collapse as a whole during the mining process of the lower middle section ore body. The reinforcement component 11 is one of a long anchor cable, a steel bar or a threaded rod.

[0050] Use YGZ-90 drilling rig or rock drilling rig to construct horizontal holes. The drilling diameter of the horizontal hole is 50-70mm, preferably 60mm; the hole depth is 20-30m, preferably 25mm; the spacing between adjacent horizontal holes is 1-2m. The horizontal hole is 3-5m above the bottom plate elevation of this section. By setting a reinforcement component 11 in the horizontal hole and reinforcing it with grouting, a reinforcement layer 25m long and 3-5m thick is finally formed (the reinforcement layer is located above the third section 3 to be mined), providing a pre-reinforced false roof for the third section 3 to be mined, thereby ensuring the safety of the mining of the ore body of the third section 3 to the greatest extent.

[0051] It should be understood that the order of step S3 (mining of the first middle section and the second middle section) and step S4 (pre-reinforcement process) can be interchanged at will, that is, the pre-reinforcement process can be performed first, and then the first middle section and the second middle section can be mined. In addition, the pre-reinforcement process can be performed before the third subsection 3 of the current middle section is mined, or it can be performed after the two-step stope of the previous middle section is mined.

[0052] S5. Mining of the third middle section:

[0053] Repeat the mining method of step S3 to mine the third segment 3, and fill it after the mining is completed. There is no need to set a "V"-shaped ore-receiving trench at the bottom of the third segment 3.

[0054] On the basis of setting the pre-reinforcement layer, no ore pillars can be reserved at the top of the third segment 3, and the ore body can be fully mined, with a high recovery rate of the ore. At the same time, the full recovery of the ore can be achieved through normal mining technology, without the need to re-recover the top pillar after traditional mining (reserving the top pillar) (re-mining and cutting engineering is required, etc.). The mining efficiency of the present invention is higher and the cost is low.

[0055] In order to further improve safety, support can be carried out on the roof of the third section 3 during mining (selectively using one or more of anchor cables, anchor rods, metal mesh or brackets for support), and then the support can be crushed.

[0056] In some cases where the safety of the pre-reinforced layer is not high, a 3-5m top pillar 13 can be reserved according to the actual situation to improve the safety of mining. Although part of the top pillar 13 may be lost at this time, the thickness of the top pillar 13 is much smaller than the thickness of the top pillar reserved in the traditional mining process, and the loss of the ore body is very small.

[0057] S6. Mining of the remaining stopes:

[0058] After the first-step mining of the same middle section is completed, the second-step mining will continue until the mining of the middle section is completed.

[0059] The next middle section is mined from top to bottom in sequence until the ore body is mined completely.

[0060] In summary, the present invention provides a safe and efficient mining method for a ore body under a large-area filling body. Through the mining process of pre-reinforcement of the empty field and subsequent filling in the segmented rock drilling stage and the joint mining of the empty field and subsequent filling in the segmented rock drilling stage, each middle section is divided into three sections. First, the segmented rock drilling stage empty field and subsequent filling mining method is adopted to recover the lower two sections, so as to maximize the production capacity of the mining field; then, a reinforcement layer is set in the bottom structure of the upper middle section to ensure that the upper filling body will not collapse as a whole during the recovery of the ore body in the lower middle section, and there is no need to set a top column or only a top column with a very small thickness needs to be set, so the mining efficiency is high, the ore recovery rate is high, the mining cost is low, and the safety is high; it can be promoted and applied in mines of the same type and has broad application prospects.

[0061] The above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A safe and efficient mining method for ore bodies under large-area filling bodies, It is characterized in that The steps include: S1. Divide the ore body into several middle sections from top to bottom along the ore body trend; each middle section is divided into a first-step stope and a second-step stope at intervals perpendicular to the ore body trend without leaving any pillars; each stope is divided into three sections from bottom to top: the first section, the second section and the third section; S2. Excavate the outer vein ramp on one side of the ore body footwall; Along the direction of the ore body, an off-vein segmented transport tunnel is excavated outside each segment, and the off-vein ramp is connected to the off-vein segmented transport tunnel; through the off-vein segmented transport tunnel, a segmented rock drilling tunnel is excavated along the lower wall of the ore body of each segment to the upper wall of the ore body, and at the same time, an ore-exiting vein is excavated to both sides of the segmented rock drilling tunnel of the first segment every 6-8m, and the ore-exiting vein is connected to the segmented rock drilling tunnel of the first segment of the adjacent stope; S3. Excavate cutting lanes and cutting shafts in the first segment near the upper wall of the ore body, blast into cutting grooves with the cutting shaft as the free surface, and then blast and mine with the cutting grooves as the free surface and compensation space, and simultaneously mine the first segment and the second segment from the upper wall of the ore body to the lower wall of the ore body, forming a "V"-shaped ore-receiving trench at the bottom of the first segment; and then fill the first segment and the second segment; S4. construct a horizontal hole in the segmented rock drilling tunnel of the second-step stope of the first segment of the upper middle segment toward the adjacent first-step stope that has been excavated and filled, the horizontal hole penetrates the filling body of the first-step stope and extends to the triangular ore pillar of the second-step stope on the other side, and a reinforcement component is arranged in the horizontal hole and reinforced by grouting; the reinforcement component is one of an anchor cable, a steel bar or a threaded rod; S5. Repeat the mining method of step S3 to mine the third segment and fill it; S6. First mine the first-step stope of the same middle section, then mine the second-step stope, until the mining of the middle section is completed; mine the next middle section from top to bottom in sequence, until the mining of the ore body is completed.

2. The safe and efficient mining method for a large-area ore body under a filling body according to claim 1, It is characterized in that In step S1, the height of the middle section is 40-60m; the widths of the first-step stope and the second-step stope are both 10-15m.

3. The safe and efficient mining method for a large-area ore body under a filling body according to claim 2, It is characterized in that In step S4, the drilling diameter of the horizontal holes is 50-70 mm, the hole depth is 20-30 m, and the row spacing between adjacent horizontal holes is 1-2 m.

4. The safe and efficient mining method for a large-area ore body under a filling body according to claim 3, It is characterized in that The horizontal hole is 3-5m away from the bottom plate of this section.

5. The safe and efficient mining method for a large-area ore body under a filling body according to claim 1, It is characterized in that The mining process in step S3 and step S5 is specifically as follows: the mining process adopts a lateral caving process, and uses a drilling rig or a YGZ90 drilling rig to construct an upward fan-shaped hole in the segmented drilling tunnel. When caving, two detonating cord detonators are loaded into the bottom blasting device for hole bottom detonation. First, a cutting groove is formed by blasting with the cutting shaft as the free surface and compensation space, and then the cutting groove is used as the free surface and compensation space for backward segmented micro-difference blasting in sequence.

6. The safe and efficient mining method for a large-area ore body under a filling body according to claim 3, It is characterized in that In step S4, a YGZ-90 drilling rig or a drilling rig is used to construct a horizontal hole.

7. The safe and efficient mining method for a large-area ore body under a filling body according to claim 2, It is characterized in that The width of the mining area is 12.5m; the height of the middle section is 50m.

8. The safe and efficient mining method for a large-area ore body under a filling body according to claim 7, It is characterized in that The heights of the first section and the second section are both 17 m, and the height of the third section is 16 m.

9. The safe and efficient mining method for a large-area ore body under a filling body according to claim 5, It is characterized in that The process of segmented micro-difference blasting is to blast 2-3 rows at a time.

10. The safe and efficient mining method for a large-area ore body under a filling body according to claim 5, It is characterized in that The collapsed ore is unloaded by scrapers; the scrapers are transported through the off-vein segmented transport tunnel, the two-step segmented rock drilling tunnel, and the vein into the affected cutting to unload the ore.

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