A low-waste combined mining method for multilayer inclined ore bodies

Abstract

The present application belongs to the technical field of filling mining process, and particularly relates to a kind of multi-layer inclined ore body low waste combined arrangement mining method, characterized by including dividing ore block structure, mining preparation engineering and stoping ore, steps are: 1) multiple stages are divided into multiple stages for multi-layer ore body, multiple panels are divided along the strike in stage, and stope is further divided in panel;2) combined mining preparation outside and inside vein is adopted, and main mining preparation network is formed;3) each stope in panel is mined by adopting segmented empty field subsequent filling mining method, and is divided into ore drawing level, rock drilling level and filling air return level from bottom to top.The present application has the advantages that: for multi-layer inclined ore body with different thickness, stope vertical strike and along strike combined arrangement is adopted, for thick ore body or multiple middle-thick ore bodies with multiple inextricable stone, stope vertical strike arrangement is adopted, for middle-thick ore body with inextricable stone, stope along strike arrangement is adopted, and multi-layer ore body is simultaneously mined, which greatly improves production capacity.

Description

Technical Field

[0001] This invention belongs to the field of filling mining technology, and particularly relates to a low-waste joint arrangement mining method for multi-layer inclined ore bodies. Background Technology

[0002] Currently, for dipping, medium-thick ore bodies with numerous vertically striking ore bodies, layered from the hanging wall to the footwall, and containing interbedded rocks both within and between ore bodies, the main mining methods employed are caving and backfilling. The caving method primarily includes sublevel caving without pillars and natural caving. Its main advantages are: simple mining structure, high flexibility, no need for pillars; simple process, full utilization of large shovels, loaders, and transporters, easy mechanization, good safety, low mining cost, and high production efficiency. The main disadvantages are: high ore dilution rate (generally 15%–40%) due to ore extraction under overburden; poor ventilation requiring dedicated ventilation tunnels; and high maintenance workload and costs. This method is essentially infeasible, especially in areas where surface movement is not permitted.

[0003] The backfilling method mainly includes segmented open-cut backfilling mining and staged open-cut backfilling mining. When mining ore bodies with these conditions, if each ore body is mined separately, although the waste rock contamination rate can be reduced, it suffers from disadvantages such as small production scale, mutual interference between ore bodies, complex mining sequence, and high management difficulty. If each ore body is mined together with the interbedded rocks, although the staged open-cut backfilling mining method with higher production capacity can be used, the waste rock contamination rate is high, the ore grade is low, and the concentrate yield is small. If the waste rock, after being processed into building materials, cannot be sold in a timely manner, it needs to occupy surface land for temporary storage, resulting in high land acquisition costs.

[0004] In summary, the caving method for multi-layered inclined ore bodies suffers from high loss and dilution rates and severe damage to the surface environment; separate mining of each ore layer results in small-scale production, complex mining sequence, and high management difficulty; mining each ore layer together with interbedded rocks leads to a high waste rock mixing rate, low ore grade, and low concentrate yield. How to improve the high-quality mining of multi-layered inclined ore bodies has always been a difficult problem in the industry and urgently needs to be solved. Summary of the Invention

[0005] The purpose of this invention is to provide a low-waste joint layout mining method for multi-layer inclined ore bodies, which overcomes the shortcomings of the prior art. The low-waste joint layout of the stope vertically and along the strike is used for mining, which reduces the waste rock mixing rate, improves production capacity, and at the same time enables safe and efficient mining without surface displacement, and improves adaptability to the ore body occurrence angle.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A low-waste combined mining method for multi-layered inclined ore bodies, characterized by including ore block structure division, preparatory engineering, and ore extraction, with the specific operation steps as follows:

[0008] 1) Divide the ore block structure, divide the multi-layered ore body into multiple stages, divide the stage into multiple panels along the strike, and further divide the panels into stopes. Among them, in the thick to very thick ore layer panels, the stopes and panel columns are divided according to the long axis of the stope perpendicular to the strike of the ore body. In the ore layer panels below the medium-thick ore body, the stopes and panel columns are divided according to the long axis of the stope along the strike of the ore body.

[0009] 2) Mining preparation project: adopts joint preparation outside and inside the vein, and takes into account the layout of the preparation project of multi-layer ore body. In the interbed of multi-layer ore body and footwall, arrange the vein connection roadway along the strike, and arrange the vertically strike cross-vein connection roadway between the pillars in the plate to form the main preparation network. Then, further construct the ore extraction connection roadway, ore extraction access roadway, trench bottom roadway, rock drilling connection roadway, rock drilling roadway, filling connection roadway, mining area intake air shaft and mining area return air shaft.

[0010] 3) Mining: Each stope in the panel is mined using the segmented open stope followed by backfilling method, which is divided into the ore extraction level, the drilling level and the backfilling and return air level from bottom to top.

[0011] The height of the stage is between 60m and 75m, and the mining area is divided into 3 to 5 sections within the stage, with a section height of 15m to 25m.

[0012] The thick to very thick ore panel includes 5 to 7 vertically oriented stopes and 1 vertically oriented panel column. The stopes are 15m to 25m wide, and the panel column is the same thickness as the stopes. The ore panel below the medium-thick ore body includes 2 to 4 strike-oriented stopes and 1 vertically oriented panel column. The stopes are 30m to 40m long, and the panel column is 15m to 25m thick.

[0013] Each ore panel is designed to have the same panel length and column width by adjusting the size and number of stopes, and to align them vertically.

[0014] In a panel, the vertically oriented stopes are mined in two steps. The first and second stopes are mined in alternating steps, and backfilling is carried out immediately after mining. In a panel, the stopes are arranged along the strike, with isolation pillars between the stopes. The isolation pillars are 4m to 6m thick, and each stope is relatively independent.

[0015] Multi-layered ore bodies consist of 2 to 3 parallel ore bodies, including a thick ore body composed of one layer of ore body thicker than 1 or multiple medium-thick ore bodies with inexhaustible interbedded stones, and 1 to 2 layers of ore bodies with medium to thin interbedded stones that can be removed.

[0016] External connecting roadways arranged along the strike within the interbedded rock of the ore body can only be arranged when the interbedded rock thickness is greater than 15m, and they also serve as pre-mining roadways for the upper and lower ore layers; when the interbedded rock thickness is less than 15m, external connecting roadways are not arranged within the interbedded rock, but must be arranged in the lower footing.

[0017] The mining sequence between stages of the multi-layered ore body adopts an upward mining sequence, mining from bottom to top in stages; the filling level of this stage is the ore extraction level after the mining of this stage ends and the production of the next stage begins; the preparation work for the bottom structure of the previous stage needs to be carried out after the production of this stage panel is completed.

[0018] In the stage of multi-layered ore bodies, when the thickness of the interbedded rocks between the ore bodies is greater than 15m, they are mined simultaneously; when the thickness of the interbedded rocks between the ore bodies is less than 15m, the ore bodies with the thickest rocks are mined first, and after the mining of the thickest rocks is completed, the ore bodies with the medium or thinnest rocks located on the hanging wall or footwall are mined.

[0019] In the lower plate of the ore body, one intake air shaft is set up for every two panels, and in the upper plate of the ore body, one return air shaft is set up for every two panels. The intake and return air shafts are arranged diagonally and staggered. The intake and return air shafts connect the horizontal and return air levels of each section.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] 1) High production capacity: For multi-layered inclined ore bodies of varying thicknesses, the stopes are arranged vertically and along the strike. For thick ore bodies or medium-thick ore bodies with multiple layers of interbedded rocks that cannot be removed, the stopes are arranged vertically. For medium-thick ore bodies with interbedded rocks that can be removed, the stopes are arranged along the strike. Through the above arrangement, multi-layered ore bodies can be mined simultaneously, which greatly improves production capacity compared to mining each layer of ore body separately in sequence.

[0022] 2) Low waste rock contamination rate: For inclined ore bodies of varying thicknesses and multiple layers, if each ore body, along with the interbedded rocks, is mined together, although a staged open-cut backfilling mining method with high production capacity can be used, the waste rock contamination rate is high, resulting in low ore grade and low concentrate yield. This invention, through a combined layout approach, adopts different stope layouts and preparatory engineering arrangements based on the occurrence conditions of different ore layers. This effectively removes interbedded rocks between ore bodies, reduces waste rock contamination rate, and improves ore grade. Simultaneously, each ore body can be mined, ensuring the mine's production capacity.

[0023] 3) High borehole utilization rate: For inclined ore bodies, if the staged open-field method is used, most of the boreholes in the hanging wall need to be drilled within the surrounding rock to meet the ore body caving requirements, resulting in a large number of unused boreholes. On the other hand, when using staged drilling over long sections, the borehole length is large, making them prone to deviation and requiring high drilling precision in the production process. The boreholes may not meet the blasting parameter requirements due to deviation, resulting in repeated drilling and unused boreholes. This invention adopts the segmented open-field method, which has strong adaptability to the ore body occurrence angle and a higher borehole utilization rate. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention;

[0025] Figure 2 for Figure 1 Cross-sectional view along line II-II, which is a schematic diagram of the vertical layout of the mining area;

[0026] Figure 3 for Figure 1 Cross-sectional view along line III-III, which is a schematic diagram of the layout of the mining area along the strike;

[0027] Figure 4 for Figure 1 The cross-sectional view along line IV-IV is a schematic diagram of the horizontal return air during filling.

[0028] Figure 5 for Figure 1 The cross-sectional view along line V-V is a schematic diagram of horizontal rock drilling.

[0029] Figure 6 for Figure 1 The cross-sectional view along line VI-VI is a schematic diagram of the ore extraction level.

[0030] In the diagram: 1-Putting wall roadway along the vein, 2-Panel cross-vein, 3-Ore extraction connecting roadway, 4-Ore extraction access roadway, 5-Cutting trench bottom roadway, 6-Drilling connecting roadway, 7-Drilling roadway, 8-Backfilling connecting roadway, 9-Mining area intake air shaft, 10-Mining area return air shaft, 11-Ore pass, 12-First-stage stope, 13-Second-stage stope, 14-Panel section pillar, 15-Mining area isolation pillar, 16-Backfilling retaining wall, 17-Backfilling pipeline, 18-Medium-deep borehole. Detailed Implementation

[0031] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0032] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the specific embodiments used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the specific embodiments described below are some embodiments of the present invention. For those skilled in the art, other specific embodiments can be obtained based on these specific embodiments without creative effort.

[0033] The components of the embodiments of the invention described and shown in the specific embodiments herein can be arranged and designed in numerous different configurations. Therefore, the following detailed description of the embodiments of the invention provided in the specific embodiments is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0034] See Figure 1-6 This is a schematic diagram of an embodiment of a low-waste joint layout mining method for multi-layered inclined ore bodies provided by the present invention, including dividing the ore block structure, preparation engineering, and ore extraction. The specific operation steps are as follows:

[0035] 1) Divide the ore block structure into multiple stages, and divide the multi-layered ore body into multiple panels along the strike within each stage. Within each panel, further divide the stopes. In the thick to very thick ore layer panels, the stopes and panel columns are divided perpendicular to the strike of the ore body along the long axis of the stopes. In the ore layer panels below the medium-thick ore body, the stopes and panel columns are divided along the strike of the ore body along the long axis of the stopes. The stage height is 60m to 75m. Within each stage, the stopes are divided into 3 to 5 sub-sections with a sub-section height of 15m to 25m.

[0036] The thick to very thick ore panels include 5 to 7 vertically aligned stopes and 1 vertically aligned panel column 14. The stopes are 15m to 25m wide, and the panel column 14 has the same thickness as the stopes. The medium-thick and thinner ore panels include 2 to 4 strike-aligned stopes and 14 vertically aligned panel columns. The stopes are 30m to 40m long, and the panel column 14 is 15m to 25m thick. The panel length and the width of the panel columns 14 are ensured to be the same for each ore panel by adjusting the size and number of stopes, and they are aligned vertically. Multi-layered ore bodies consist of 2 to 3 parallel layers, including one thick ore body or multiple medium-thick ore bodies composed of inexhaustible interbedded stones, and 1 to 2 thinner ore bodies with extruded interbedded stones.

[0037] 2) Preparatory work: A combined on-vein and off-vein preparatory approach is adopted, comprehensively considering the layout of preparatory works for multiple ore bodies. The preparatory work is divided into three levels from bottom to top: the ore-producing level, the drilling level, and the backfilling and return air level. The main preparatory network at each level consists of two footwall roadways 1 along the ore body strike and multiple panel crosscuts 2 perpendicular to the ore body strike. The remaining preparatory works are gradually constructed from the main preparatory network. The specific construction sequence is as follows:

[0038] After the main mining network is formed at the ore extraction level, for thick to very thick ore layers, ore extraction connecting roadway 3 is constructed perpendicular to the ore body along the vein roadway 1 from the footwall. Then, ore extraction access roadway 4 is constructed from ore extraction connecting roadway 3, followed by the construction of the trench bottom roadway 5. For ore layers of medium thickness or less, ore extraction access roadway 4 is constructed directly from the footwall along the vein roadway 1 perpendicular to the ore body, followed by the construction of the trench bottom roadway 5.

[0039] After the main mining preparation network is formed by horizontal drilling, the connecting drilling roadway 6 is constructed from the footwall along the vein roadway 1 perpendicular to the ore body strike, and the drilling roadway 7 is constructed along the long axis of the mining area.

[0040] After the main mining network is formed by filling the return air horizontally, the connecting roadway 8 is constructed from the footwall along the vein roadway 1 perpendicular to the ore body strike.

[0041] The intake air shaft 9, return air shaft 10, and ore pass 11 vertically connect the ore extraction level, drilling level, and backfilling return air level. The intake air shaft 9 and return air shaft 10 are arranged diagonally at intervals, forming a two-wing diagonal ventilation system to supply air to each level. The ore pass 11 is located in the footwall or within the interbedded rock of the ore body, with one pass in each footwall, responsible for lowering ore to each level.

[0042] 3) After the mining and cutting work is completed, a medium-deep hole drilling jumbo is used to drill medium-deep holes 18 in the drilling roadway 7, and ore is blasted laterally with the cutting groove as the free face. After each blast, 1 / 3 of the blasted ore is removed, and the remaining ore is left on the sidewalls of the stope support. The three sections can be mined simultaneously, with the upper section leading the lower section by 5-10m. After all the ore in the stope has been blasted, the blasted ore is piled in the bottom roadway 5 of the trench, and a loader is used to extract a large amount of ore in a high-intensity concentrated manner in the ore extraction route 4, and then unloaded into the ore pass 11 through the panel crossbeam 2.

[0043] 4) Ventilation: One intake air shaft 9 is installed for every two panels in the footwall of the ore body, and one return air shaft 10 is installed for every two panels within the interbedded rock of the ore body. The intake and return air shafts are diagonally staggered, connecting the various sub-levels and the return air level. Ventilation during the mining process mainly utilizes the fresh airflow in the footwall roadway 1 of the ore extraction level. This fresh air enters the mining face at each level through the intake air shaft 9, cleans the working face, and then returns the polluted air through the return air shaft 10 to the footwall roadway 1 of the filling return air level, forming a through-flow ventilation.

[0044] 5) Backfilling: After mining, a backfilling retaining wall 16 is built in the bottom ore access road 6, and a backfilling pipeline 17 is installed in the backfilling connecting roadway 8, and then backfilling of the mining area is carried out.

[0045] 6) Mining sequence

[0046] Within the phase, the mining sequence is as follows: the stopes arranged vertically within the panel are divided into two-step mining, with the first-step stope 12 and the second-step stope 13 being mined in an alternating manner; the stopes arranged along the strike within the panel are separated by stope isolation pillars 15, which are 4m to 6m thick. Each stope is relatively independent and can be mined simultaneously.

[0047] The inter-stage mining sequence for multi-layered ore bodies adopts an upward mining sequence, mining from bottom to top in stages; the filling level of this stage is the ore extraction level after the mining of this stage ends and the production of the next stage begins; the preparation work for the bottom structure of the previous stage needs to be carried out after the production of this stage panel is completed.

[0048] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A low-waste combined mining method for multi-layered inclined ore bodies, characterized in that, The process includes dividing the ore block structure, preparation engineering, and ore extraction. The specific operational steps are as follows: 1) Divide the ore block structure and divide the multi-layered ore body into multiple stages. Within each stage, divide the blocks along the strike. Within each block, further divide the stopes. In the thick to very thick ore layer blocks, divide the stopes and blocks into columns perpendicular to the strike of the ore body along the long axis of the stopes. In the ore layer blocks below the medium-thick ore body, divide the stopes and blocks into columns along the strike of the ore body along the long axis of the stopes. 2) Mining preparation project: adopts joint preparation outside and inside the vein, and takes into account the layout of the preparation project of multi-layer ore body. In the interbed of multi-layer ore body and footwall, arrange the vein connection roadway along the strike, and arrange the vertically strike cross-vein connection roadway between the pillars in the plate area to form the main preparation network. Then, further construct the ore extraction connection roadway, ore extraction access roadway, trench bottom roadway, rock drilling connection roadway, rock drilling roadway, filling connection roadway, mining area intake air shaft and mining area return air shaft. 3) Mining: Each stope in the panel is mined using the subdivided stope followed by backfilling method, which is divided into the ore extraction level, the drilling level and the backfilling return air level from bottom to top; The stage height is 60m to 75m, and the mining area is divided into 3 to 5 sections within the stage, with a section height of 15m to 25m; Within the thick to very thick ore body panel, there are 5 to 7 vertically oriented stopes and 1 vertically oriented panel column. The stopes are 15m to 25m wide, and the panel column is the same thickness as the stopes. Within the ore body panel below the medium-thickness ore body, there are 2 to 4 strike-oriented stopes and 1 vertically oriented panel column. The stopes are 30m to 40m long, and the panel column is 15m to 25m thick. Each ore panel is designed to have the same panel length and column width by adjusting the size and number of stopes, and to align them vertically. The vertically arranged stopes within the panel are divided into two-step mining. The first and second stopes are mined in an alternating manner, and backfilling is carried out immediately after mining. The stopes arranged along the strike within the panel are equipped with isolation pillars with a thickness of 4m to 6m, and each stope is relatively independent. Multi-layered ore bodies consist of 2 to 3 parallel ore bodies, including a thick ore body consisting of one layer of ore body thicker than 1 or multiple medium-thick ore bodies with inexhaustible interbedded stones, and 1 to 2 layers of ore bodies with medium to thin interbedded stones that can be removed. External connecting roadways arranged along the strike within the interbedded rock of the ore body can only be arranged when the thickness of the interbedded rock is greater than 15m, and they also serve as pre-mining roadways for the upper and lower ore layers. When the thickness of the interbedded rock is less than 15m, external connecting roadways are not arranged within the interbedded rock, but external connecting roadways must be arranged in the lower footing. The inter-stage mining sequence of multi-layered ore bodies adopts an upward mining sequence, mining from bottom to top in stages; the filling level of this stage is the ore extraction level after the mining of this stage ends and the production of the next stage begins; the preparation work for the bottom structure of the previous stage needs to be carried out after the production of this stage panel is completed. In the stage of multi-layered ore bodies, when the thickness of the interbedded rocks between the ore bodies is greater than 15m, they are mined simultaneously; when the thickness of the interbedded rocks between the ore bodies is less than 15m, the ore bodies with the thickest rocks are mined first, and after the mining of the thickest rocks is completed, the ore bodies with the medium or thinnest rocks located on the hanging wall or footwall are mined. In the lower plate of the ore body, one intake air shaft is set up for every two panels, and in the upper plate of the ore body, one return air shaft is set up for every two panels. The intake and return air shafts are arranged diagonally and staggered. The intake and return air shafts connect the horizontal and return air levels of each section.

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