Safe, efficient and low-mining-cutting-ratio large-diameter deep hole mining method under broken ore rock condition

Abstract

The invention provides a safe, efficient and low-mining-cutting-ratio large-diameter deep hole mining method under the condition of broken ore rock, and belongs to the field of underground mine mining. Firstly, a rock drilling chamber, a rock drilling roadway and a cutting groove are formed in a stope, a downward inclined deep hole and a large-diameter vertical deep hole extending to the bottom of the stope are constructed downwards from the rock drilling chamber, and empty holes are supplemented and constructed; a hole distribution structure with alternately arranged empty holes and large-diameter vertical deep holes is formed in the two boundaries of the stope, and the functions of separating and controlling the boundaries of the stope are achieved during blasting. According to the method, the stope and the hole distribution structure are optimized, the mining-to-cutting ratio is reduced, the stope has no ore loss on the design level, the hole distribution structure of the stope boundary enables the blasting energy to advance towards the empty hole and the compensation space more accurately, direct impact of the blasting energy on the lateral wall is reduced, control over the stope boundary is facilitated, and the blasting efficiency is improved. Roof and lateral wall damage or surrounding rock, filling body and other instability conditions caused by blasting vibration are avoided, and the safety of stope stoping under the broken ore rock condition is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of underground mining, and particularly relates to a large-diameter long-hole mining method with safe, efficient and low extraction ratio under the conditions of broken ore and rock. Background Art

[0002] In view of the mining technical conditions of inclined or steeply inclined thick and large ore bodies under the conditions of low-grade broken ore and rock, most mines adopt the sublevel filling mining method or the drift filling mining method for mining, and a small number of mines adopt the sublevel medium-deep hole mining method with small structural parameters for mining. The above mining methods all have problems such as large drivage work amount, high extraction ratio and low production efficiency. In addition, when sublevel medium-deep holes are used for mining, there is generally a serious situation of roof and side wall damage, which is mainly caused by the instability of surrounding rock or other stope ore bodies, filling bodies, etc. induced by blasting vibration. This will lead to an increase in the dilution and loss indexes of the stope, an increase in the safety risk of construction, and seriously affect the safe and efficient production of the mine.

[0003] In the prior art, a certain invention patent discloses a fan-shaped medium-diameter long-hole mining process for steeply inclined medium-thick ore bodies. An along-strike haulage roadway and a drilling chamber are arranged at the upper part of the stope; an along-strike haulage roadway, an ore-drawing drift, a loading drift and a sill drift are arranged at the lower part; bottom and top cut cross headings are correspondingly arranged in the center or at the end of the stope, and a cut raise is driven in the hanging wall of the ore body to penetrate the bottom and top cut cross headings; upward medium-deep holes are drilled in the sill drift and the bottom cut cross heading, and blasting forms a medium-deep hole cut groove and a V-shaped ore-drawing trench; in the top cut cross heading, downward medium-diameter parallel and fan-shaped inclined long holes are arranged, and blasting forms a cut slot; then, taking the cut slot as a free surface, downward medium-diameter fan-shaped long holes are blasted in the drilling chamber along the ore room strike to realize lateral ore caving. In this mining process, upward medium-deep holes, fan-shaped medium-deep holes, vertical medium-deep holes, downward medium-diameter inclined long holes, medium-diameter fan-shaped inclined long holes and medium-diameter parallel inclined long holes are arranged in the stope for blasting recovery of the stope, which makes the drivage engineering layout difficult, the extraction ratio large and the process complex; and in this process, an ore-drawing trench is arranged at the bottom of the stope, forming a residual sill pillar, resulting in waste of ore resources and reducing the mining benefit of the mine. Summary of the Invention

[0004] In view of the technical problems existing in the background art, the present application provides a large-diameter long-hole mining method with safe, efficient and low extraction ratio under the conditions of broken ore and rock, aiming to solve the technical problems of large drivage work amount, high extraction ratio, low production efficiency and poor stope stability and safety during the mining process of ore bodies under the conditions of broken ore and rock.

[0005] The embodiment of the present application provides a large-diameter long-hole mining method with safe, efficient and low extraction ratio under the conditions of broken ore and rock, including the following steps: S1. Divide the orebody to be mined under the condition of broken ore and rock into several levels in height, and divide each level into several stopes along the strike of the orebody; there are two drilling chambers respectively near the two boundaries of the stope at the top of the stope, and a drilling roadway is arranged in the middle at the bottom. Both the drilling chambers and the drilling roadway are arranged along the mining direction of the stope orebody. A cutting slot perpendicular to the drilling roadway is also arranged in the stope. S2. Before the stope is mined, large-diameter vertical holes and downward inclined holes are constructed downward from the drilling chambers, which are evenly arranged along the mining direction of the stope orebody. The large-diameter vertical holes extend to the bottom of the stope; empty holes extending to the bottom of the stope are additionally constructed between the large-diameter vertical holes near the two boundaries of the stope, so as to form a hole layout structure in which the empty holes and the large-diameter vertical holes are alternately arranged at the two boundaries of the stope. S3. Charge, blast and ore-draw the large-diameter vertical holes and the downward inclined holes to realize the stoping of the stope. S4. Use high-strength filling body to fill the mined-out stope, and repeat steps S2 - S3 to mine other stopes in the same level. Finally, mine all levels from bottom to top.

[0006] As a further improvement of the present invention, in step S2, the hole spacing of the large-diameter vertical holes in the mining direction of the stope orebody is 3.0 - 3.5 m, and the empty holes are arranged at the middle positions between two adjacent large-diameter vertical holes; the aperture of the large-diameter vertical holes is 100 - 150 mm, and the aperture of the empty holes is 60 - 80 mm.

[0007] As a further improvement of the present invention, in step S1, the cutting slot is arranged at the middle position of the stope, penetrates the entire stope in height, and has a width of 3 - 4 m along the mining direction of the stope orebody.

[0008] As a further improvement of the present invention, the stope is mined step by step in the way of mining every other one. Before mining a step stope, several ore-drawing cross-cuts are constructed from the drilling roadways in the two adjacent step stopes on both sides to the step stope. The ore-drawing cross-cuts extend to the stope boundary of the step stope for ore-drawing of the step stope.

[0009] As a further improvement of the present invention, in step S1, before the level is mined, the drilling chambers in the stope are jointly supported by bolts, cable bolts and wire mesh, and the surface of the drilling chambers is sprayed with concrete; the drilling roadway at the bottom of the stope in the lowest level is pre-supported, and horizontal blast holes perpendicular to the sidewall of the drilling roadway are constructed at its bottom. The horizontal blast holes are pre-blasted by means of interval charging along the strike of the drilling roadway to separate the stope floor and the bottom surrounding rock of this level.

[0010] As a further improvement of the present invention, in step S2, the burden of the large-diameter vertical deep holes is 3.0 - 3.5 m, and the hole spacing of the downwardly inclined deep holes in the ore body mining direction of the stope is 3.0 - 3.5 m.

[0011] As a further improvement of the present invention, the aperture of the downwardly inclined deep holes is 100 - 120 mm. The downwardly inclined deep holes incline from the drifts for drilling to the middle area of the ore body in the stope, and the angle with the vertical plane is 60° - 70°, so as to ensure the blasting effect of the ore body inside the stope and ensure uniform blasting fragmentation.

[0012] As a further improvement of the present invention, in step S2, before the stope is mined, horizontal shallow holes are constructed in the stulls between the two drifts for drilling, and are charged and blasted together with the normal blasting face in step S3 to realize the recovery of the stulls.

[0013] As a further improvement of the present invention, the angle between the ore-drawing crosscut and the drift for drilling is 40° - 50°, and the spacing of the ore-drawing crosscuts along the trend of the drift for drilling is 10 - 12 m.

[0014] As a further improvement of the present invention, before the mining of each level starts, the ore preparation and cutting engineering of the ore body is carried out, including the level haulage roadway arranged between each level and along the trend of the ore body.

[0015] Beneficial effects: (1) The large-diameter deep hole mining method with safe, efficient and low mining and cutting ratio under the condition of broken ore and rock of the present invention first sets two drifts for drilling at the top of the stope, a drift for drilling in the middle at the bottom, and a cut-off slot perpendicular to the drift for drilling as a compensation space. Downwardly inclined deep holes are constructed downward from the drifts for drilling and large-diameter vertical deep holes extending to the bottom of the stope, and empty holes extending to the bottom of the stope are additionally constructed to form a hole layout structure with alternating empty holes and large-diameter vertical deep holes at both boundaries of the stope, which plays a role in separating and controlling the stope boundary during blasting. Through the optimization of the stope and the hole layout structure, there is no ore loss at the design level of the stope, and the layout of the empty holes at the stope boundary makes the detonation energy generated by the explosive blasting travel more precisely towards the empty holes and the compensation space direction, reducing the direct impact of the detonation energy on the side wall. After blasting, the side wall forms better, and the side wall surface is flatter, which is beneficial to the control of the stope boundary and avoids the situations of roof, side wall damage or instability of surrounding rock, filling body, etc. induced by blasting vibration, improving the safety of stope mining under the condition of broken ore and rock.

[0016] (2) By arranging large-diameter vertical deep holes and empty holes alternately at the stope boundary in the present invention and defining their dimensional parameters, the empty holes without charge play the roles of air interval and diversion during blasting, which is beneficial to controlling the blasting effect, reducing the damage to the sidewall of the stope, and avoiding the problem of the collapse of the sidewall surrounding rock or filling body. Moreover, the hole arrangement structure and its functions provide the possibility for the ore body with broken ore rock conditions to be mined by large-diameter deep holes, reduce the mining and cutting ratio, improve the mining efficiency of the broken ore body, and enable the stope to be mined safely and efficiently. In addition, by setting a cut groove in the stope, a compensation space is provided for the blasting of the stope, reducing the direct impact of the detonation energy on the sidewall, effectively controlling the collapse of the sidewall, and being beneficial to controlling the blasting effect.

[0017] (3) By optimizing the stope structure and cooperating with the mining technology in the present invention, the ore drawing in the stope is more convenient. Moreover, by adopting the large-diameter vertical deep hole blasting caving and non-pillar stoping method that directly extends to the bottom of the stope, the ore-drawing crosscut does not need to extend to the drilling roadway of the current stope, reducing the mining and cutting ratio and making the stoping of the stope more efficient.

[0018] The above description is only an overview of the technical solution of this application. In order to be able to understand the technical means of this application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of this application more obvious and understandable, the following specifically gives the specific implementation manners of this application. Brief Description of the Drawings

[0019] In order to more clearly illustrate the technical solution of this application, the drawings used in this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to these drawings.

[0020] Figure 1 It is a schematic diagram of the stope structure of the large-diameter deep hole mining method with safe and efficient, low mining and cutting ratio under the condition of broken ore rock in the embodiment of this application; Figure 2 is Figure 1 the schematic diagram of the stope structure in the II-II direction of Figure 3 is Figure 1 the schematic diagram of the stope structure in the III-III direction of Description of the reference numerals: 100, level; 110, stope; 120, drilling chamber; 121, large-diameter vertical deep hole; 122, downward inclined deep hole; 123, empty hole; 124, horizontal shallow hole; 130, drilling roadway; 131, horizontal blast hole; 140, cut groove; 150, ore-drawing crosscut; 160, rib pillar; 170, level haulage drift; 180, combined support structure. Detailed implementation manners

[0021] The embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to illustrate the technical solutions of the present application more clearly, and thus are only examples and cannot be used to limit the protection scope of the present application.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the description and claims of this application and the above drawings are intended to cover non-exclusive inclusion.

[0023] In the description of the embodiments of this application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity, specific order, or primary-secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "a plurality" and "several" is more than two, unless otherwise specifically defined.

[0024] Referring to "embodiments" herein means that the specific features, structures, or characteristics described in connection with the embodiments may be included in at least one embodiment of this application. The phrase appears in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein may be combined with other embodiments.

[0025] In the description of the embodiments of this application, the orientation or positional relationship indicated by technical terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the embodiments of this application.

[0026] At present, for the mining technical conditions of inclined or steeply inclined thick ore bodies under the conditions of low-grade broken ore rock, most mines adopt the sublevel filling mining method or the drift filling mining method for mining, and a small number of mines adopt the sublevel medium-deep hole mining method with small structural parameters. The above mining methods all have problems such as large development engineering quantity, high extraction ratio, and low production efficiency. In addition, when using sublevel medium-deep hole mining, there is generally a serious situation of roof and side wall damage, which is mainly caused by the instability of surrounding rock or other stope ore bodies, filling bodies, etc. induced by blasting vibration. This will lead to an increase in dilution and loss indexes of the stope, an increase in construction safety risks, and seriously affect the safe and efficient production of the mine. Moreover, the mining process steps of the existing technology are complex and fail to well solve the technical problems existing in the mining process of inclined or steeply inclined thick ore bodies under the conditions of low-grade broken ore rock.

[0027] In order to solve the technical problems of large development engineering quantity, high extraction ratio, low production efficiency, and poor stope stability and safety existing in the mining process of ore bodies under the conditions of broken ore rock, this application provides a large-diameter deep hole mining method with safe and efficient operation and low extraction ratio under the conditions of broken ore rock. By setting a drilling chamber at the top of the stope, a drilling roadway in the middle at the bottom, and a cut groove perpendicular to the drilling roadway as a compensation space, downward inclined deep holes are constructed downward from the drilling chamber and large-diameter vertical deep holes extending to the bottom of the stope, and empty holes extending to the bottom of the stope are additionally constructed to form a hole layout structure in which empty holes and large-diameter vertical deep holes are alternately arranged at both boundaries of the stope, which plays a role in separating and controlling the stope boundary during blasting. Through the optimization of the stope and the hole layout structure, there is no ore loss at the design level of the stope, and the layout of the empty holes at the stope boundary makes the detonation energy generated by explosive blasting travel more accurately in the direction of the empty holes and the compensation space. After blasting, the side wall forms better, and the side wall surface is more flat, which is conducive to the control of the stope boundary and avoids the situation of roof and side wall damage or instability of surrounding rock, filling bodies, etc. induced by blasting vibration, and improves the safety of stope stoping under the conditions of broken ore rock.

[0028] For the convenience of description, the following embodiments are described by taking a large-diameter deep hole mining method with safe and efficient operation and low extraction ratio under the conditions of broken ore rock in an embodiment of this application as an example.

[0029] Please refer to Figures 1 to 3 , an embodiment of this application provides a large-diameter deep hole mining method with safe and efficient operation and low extraction ratio under the conditions of broken ore rock, including the following steps: S1. Divide the ore body to be mined under the condition of broken ore and rock into several levels 100 in height, and divide each level 100 into several stopes 110 along the strike of the ore body; there are two drilling chambers 120 respectively close to the two boundaries of the stope at the top of the stope 110 (the outer boundary of the drilling chamber 120 coincides with the boundary of the stope 110 where it is located), and a drilling roadway 130 is provided in the middle at the bottom. Both the drilling chamber 120 and the drilling roadway 130 are arranged along the mining direction of the stope ore body. A cut groove 140 perpendicular to the drilling roadway 130 is also provided in the stope 110; S2. Before the stope 110 is mined, large-diameter vertical deep holes 121 and downward inclined deep holes 122 are constructed downward from the drilling chamber 120 and arranged uniformly along the mining direction of the stope ore body. The large-diameter vertical deep holes 121 extend to the bottom of the stope 110; blank holes 123 extending to the bottom of the stope 110 are additionally constructed between the large-diameter vertical deep holes 121 close to the two boundaries of the stope 110, so as to form a hole layout structure in which the blank holes 123 and the large-diameter vertical deep holes 121 are alternately arranged at the two boundaries of the stope 110; S3. Charge, blast and extract ore from the large-diameter vertical deep holes 121 and the downward inclined deep holes 122 to realize the stoping of the stope 110; S4. Fill the mined-out stope 110 with high-strength filling body, and repeat steps S2 - S3 to mine other stopes 110 in the same level 100. Finally, mine all levels 100 from bottom to top.

[0030] In this stope method, through the optimization of the stope and the hole layout structure, there is no ore loss in the design of the stope 110. Moreover, the arrangement of the blank holes 123 at the stope boundary makes the detonation energy generated by the explosive blasting travel more accurately towards the blank holes 123 and the compensation space direction, reducing the direct impact of the detonation energy on the side wall. After blasting, the side wall takes a better shape, and the side wall surface is more flat, which is beneficial to the control of the stope boundary, avoiding the damage of the roof and side wall or the instability of the surrounding rock, filling body, etc. induced by blasting vibration, and improving the safety of the stoping of the stope 110. It should be noted that Figures 1 to 3 This is only a schematic diagram of the stope structure of an embodiment of the present application, Figure 3 The black lines on both sides of the stope in the figure indicate the role of controlling the stope boundary during the blasting of the hole layout structure.

[0031] Further, in some embodiments, in step S2, the hole spacing of the large-diameter vertical deep holes 121 in the mining direction of the stope ore body is 3.0 - 3.5 m, and the blank holes 123 are arranged in the middle position between two adjacent large-diameter vertical deep holes 121; the aperture of the large-diameter vertical deep holes 121 is 100 - 150 mm, and the aperture of the blank holes 123 is 60 - 80 mm.

[0032] In the technical solution of the embodiment of the present application, by staggering the large-diameter vertical deep holes 121 and the empty holes 123 at the stope boundary and defining their dimensional parameters, the empty holes 123 without charge play the role of air interval and diversion during blasting, which is beneficial to controlling the blasting effect, reducing the damage to the side wall of the stope 110, and avoiding the problem of the collapse of the side wall surrounding rock or filling body; moreover, the hole layout structure and its function provide the possibility for the large-diameter deep hole mining of ore bodies under broken ore-rock conditions, reduce the overall development ratio of the stope, improve the mining efficiency of the broken ore body, and enable the stope to be mined safely and efficiently.

[0033] Further, in some embodiments, in step S1, the cut groove 140 is arranged at the middle position of the stope 110, runs through the entire stope 110 in height, and has a width of 3.0 - 4.0 m along the ore body mining direction of the stope.

[0034] In the technical solution of the embodiment of the present application, by arranging the cut groove 140 in the stope 110, a compensation space is provided for the blasting of the stope 110, reducing the direct impact of the detonation energy on the side wall, effectively controlling the collapse of the side wall, and being beneficial to controlling the blasting effect.

[0035] Further, in some embodiments, the stope 110 is mined step by step in an alternate mining method. Before the mining of one-step stope, several ore-drawing cross-cuts 150 are constructed from the drilling headings 130 in the adjacent two-step stopes on both sides to the one-step stope. The ore-drawing cross-cuts 150 extend to the stope boundary of the one-step stope for ore drawing of the one-step stope. The included angle between the ore-drawing cross-cuts 150 and the drilling headings 130 is 40° - 50°, and the spacing of the ore-drawing cross-cuts 150 along the heading direction of the drilling headings 130 is 10 - 12 m.

[0036] In the technical solution of the embodiment of the present application, by optimizing the stope structure and cooperating with the mining process, the ore drawing of the one-step stope is made more convenient; moreover, the large-diameter vertical deep holes 121 directly extending to the bottom of the stope 110 are used for blasting ore caving and the pillarless stoping method, so that the ore-drawing cross-cuts 150 do not need to extend to the drilling headings 130 of the current stope, reducing the development ratio and making the stoping of the stope 110 more efficient.

[0037] Further, in some embodiments, in step S1, before the exploitation of the middle section 100, a combined support structure 180 of anchor bolts, cable bolts and wire mesh is arranged in the drilling chamber 120 in the stope 110, and the surface of the drilling chamber 120 is treated with shotcrete; the drilling roadway 130 at the bottom of the stope in the lowermost middle section 100 is pre - supported, and horizontal blast holes 131 perpendicular to the side wall of the drilling roadway 130 are constructed at its bottom. The horizontal blast holes 131 are pre - blasted in a spaced - charge manner along the trend of the drilling roadway 130 (i.e., blasted before the stope mining), separating the floor of the stope 110 from the bottom surrounding rock. The aperture of the horizontal blast holes 131 is 60 - 80 mm, the length is 5 - 6 m, and the row spacing of the horizontal blast holes 131 along the trend of the drilling roadway 130 where they are located is 1.0 - 1.2 m.

[0038] In the technical solution of the embodiment of the present application, pre - splitting blasting is carried out on the lower part of the stope 110 in the lowermost middle section 100 by using horizontal blast holes 131, separating the floor of the stope 110 in this middle section 100 from the bottom surrounding rock, which is beneficial to the control of the blasting of the ore body by the large - diameter vertical deep holes 121, beneficial to the stability of the stope mining, avoiding the damage to the bottom surrounding rock and increasing the dilution of the ore; and separating the stope 110 from the bottom boundary in advance can also effectively alleviate the problem of remaining footwall at the bottom of the stope 110 when the large - diameter vertical deep holes 121 and the downward - inclined deep holes 122 are blasted, which is more beneficial to ore drawing.

[0039] Further, in some embodiments, the construction process of the combined support structure 180 is as follows: Shotcrete is applied to the drilling chamber 120 with a thickness of 20 mm. Then, resin anchor bolt and cable bolt holes are constructed on the roof. After all the resin anchor bolts and cable bolts are installed in the corresponding holes, the wire mesh is laid, and the wire mesh is fixed with the gaskets for fixing the orifices of the anchor bolts and cable bolts, so that the wire mesh fits the rock wall. Grouting reinforcement treatment is carried out in the cable bolt holes, so that the cement mortar penetrates into the surrounding rock through the cracks of the cable bolt holes, thereby achieving the purpose of consolidating the rock layer and enhancing the stability of the rock layer; the cable bolts also need to apply prestress with special equipment, so that the rock layers penetrated by the cable bolts can be tightly fitted together, thus playing a role in strengthening the rock layer and preventing the roadway from collapsing and deforming. After all the anchor bolts, cable bolts and wire mesh are constructed, the surface of the drilling chamber 120 is treated with shotcrete again, and the thickness of the shotcrete layer is 20 mm, making its integrity stronger. The tension of the cable bolts can act on the surface of the chamber as a whole through the wire mesh and the shotcrete layer, protecting the roof from being damaged.

[0040] Further, in some embodiments, in step S2, the row spacing of the large-diameter vertical deep holes 121 is 3.0 - 3.5 m, and the hole spacing of the downward inclined deep holes 122 in the ore body mining direction of the stope 110 is 3.0 - 3.5 m. The aperture of the downward inclined deep holes 122 is 100 - 120 mm. The downward inclined deep holes 122 incline from the drilling chamber 120 to the middle area of the ore body in the stope 110, and the included angle with the vertical plane is 60° - 70°, so as to ensure the blasting effect of the ore body inside the stope 110 and ensure uniform blasting fragmentation. It should be noted that in the actual mining process, those skilled in the art can adaptively adjust parameters such as the layout range, quantity, and length dimension of the downward inclined deep holes 122 according to the actual ore body and requirements.

[0041] Further, in some embodiments, in step S2, before the stope 110 is mined, horizontal shallow holes 124 are constructed in the stull 160 between the two drilling chambers 120 of the stope 110, and are charged and blasted together with the normal blasting face in step S3 to realize the recovery of the stull 160.

[0042] In the technical solution of the embodiment of the present application, the stull 160 between the two drilling chambers 120 is recovered by constructing the horizontal shallow holes 124, and 100% recovery of the stope is achieved at the design level, improving the mining economic benefit of the mine.

[0043] Further, in some embodiments, before the mining of each level 100 starts, the ore body development and cutting project is carried out, including the level haulage adit 170 arranged between each level 100 and along the ore body strike.

[0044] Specific embodiments are listed below. It should be noted that the embodiments described below are exemplary and are only used to explain the present application, and should not be construed as a limitation to the present application. For those not specified in the embodiments, the techniques or conditions described in the literature in the art or according to the product specifications are followed.

[0045] Example 1 This embodiment provides a large-diameter deep-hole mining method with safety, high efficiency, and low mining and cutting ratio under broken ore and rock conditions, and its practical application in inclined thick ore bodies under low-grade broken ore and rock conditions, including the following steps: S1. Divide the orebody to be mined under the condition of broken ore and rock into several levels in height (height 20 m), and divide it into several stopes (width 15 m) along the strike of the orebody within each level; there are two drilling chambers (width 5.5 m) near the two boundaries of the stope respectively at the top of the stope (the outer boundary of the drilling chamber coincides with the boundary of the stope where it is located), and a drilling roadway (width 5.5 m) is provided in the middle at the bottom. The drilling chambers and the drilling roadway are both arranged along the mining direction of the orebody in the stope. A cutting slot perpendicular to the drilling roadway is also provided at the middle position of the stope. The cutting slot penetrates the entire stope in height and has a width of 3.0 m; The stopes are mined step by step in the way of mining every other one. Before mining a step stope, several ore-drawing cross-cuts are constructed from the drilling roadways in the two adjacent two-step stopes on both sides to the step stope. The ore-drawing cross-cuts extend to the stope boundary of the step stope for ore drawing of the step stope; the included angle between the ore-drawing cross-cuts and the drilling roadway is 45°, and the spacing along the trend of the drilling roadway is 10 m; Before the mining of the level, the drilling chambers are supported by the combined support of anchor bolts, cable bolts and wire mesh, and the surface of the drilling chambers is treated with shotcrete; the drilling roadway at the bottom of the stope in the lowest level is pre-supported, and horizontal blast holes perpendicular to the sidewall of the drilling roadway are constructed at its bottom. The horizontal blast holes are pre-blasted by the way of interval charging along the trend of the drilling roadway to separate the floor of the stope from the surrounding rock at the bottom; the aperture of the horizontal blast holes is 60 mm, the length is 6 m, and the row spacing of the horizontal blast holes along the trend of the drilling roadway where they are located is 1.2 m; S2. Before the mining of the stope, large-diameter vertical deep holes and downward inclined deep holes are constructed downward from the drilling chambers and arranged uniformly along the mining direction of the orebody in the stope. The large-diameter vertical deep holes extend to the bottom of the stope; blank holes extending to the bottom of the stope are additionally constructed between the large-diameter vertical deep holes near the two boundaries of the stope to form a hole layout structure with alternating blank holes and large-diameter vertical deep holes at the two boundaries of the stope; at the same time, horizontal shallow holes are constructed in the rib pillar between the two drilling chambers of the stope. Among them, the hole spacing of the large-diameter vertical deep holes along the mining direction of the orebody in the stope is 3.4 m, and the blank holes are arranged in the middle position between two adjacent large-diameter vertical deep holes, with a distance of 1.7 m from them; the aperture of the large-diameter vertical deep holes is 120 mm, and the aperture of the blank holes is 60 mm; the row spacing of the large-diameter vertical deep holes is 3.4 m, and the hole spacing of the downward inclined deep holes along the mining direction of the orebody in the stope is 3.4 m. The aperture of the downward inclined deep holes is 120 mm, and the downward inclined deep holes incline from the drilling chamber to the middle area of the orebody in the stope, and the included angle with the vertical plane is 65°; S3. Charge, blast and ore draw the large-diameter vertical deep holes, downward inclined deep holes and horizontal shallow holes to realize the stoping of the stope; S4. Use high-strength filling bodies to fill the mining area after mining, and repeat steps S2 to S3 to mine other mining areas in the same middle section, and finally mine all the middle sections from bottom to top.

[0046] The mining method of this embodiment ensures that there is no ore loss in the mining area at the design level, and the setting of the special hole layout structure at the boundary of the mining area allows the detonation energy generated by the blasting of explosives to move more accurately in the direction of the empty holes and the compensation space, reducing the direct impact of the detonation energy on the side walls. After the blasting, the side walls are better formed and the side wall surface is smoother, which is beneficial to the control of the mining area boundary, avoids the damage of the roof and side walls or the instability of the surrounding rock and filling body caused by the blasting vibration, and improves the safety of mining in the mining area.

[0047] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present application.

Claims

1. A large-diameter deep-hole mining method that is safe, efficient, and has a low mining-to-cut ratio under broken ore and rock conditions, characterized in that: The following steps are involved: S1. Divide the ore body to be mined under the condition of broken ore rock into several middle sections in height, and divide the middle sections into several stopes along the direction of the ore body; the top of the stope is provided with two rock drilling chambers close to the two boundaries of the stope respectively, and the middle of the bottom is provided with a rock drilling tunnel, and the rock drilling chamber and the rock drilling tunnel are both arranged along the mining direction of the ore body in the stope, and the stope is also provided with a cutting groove perpendicular to the rock drilling tunnel; S2. Before mining in the stope, the rock drilling chamber constructs large-diameter vertical deep holes and downward inclined deep holes evenly arranged along the mining direction of the ore body in the stope, and the large-diameter vertical deep holes extend to the bottom of the stope; additional empty holes extending to the bottom of the stope are constructed between the large-diameter vertical deep holes near the two boundaries of the stope, so as to form a hole arrangement structure in which empty holes and large-diameter vertical deep holes are alternately arranged at the two boundaries of the stope; S3, charging, blasting and unloading the large-diameter vertical deep hole and the downward inclined deep hole to realize the recovery of the stope; S4. Use high-strength filling bodies to fill the mining area after mining, and repeat steps S2 to S3 to mine other mining areas in the same middle section, and finally mine all the middle sections from bottom to top.

2. The large-diameter deep hole mining method according to claim 1, which is safe, efficient and low mining-cutting ratio under broken ore and rock conditions, is characterized in that: In step S2, the hole spacing of the large-diameter vertical deep holes along the mining direction of the ore body in the stope is 3.0-3.5 m, and the empty hole is arranged in the middle position of two adjacent large-diameter vertical deep holes; the aperture of the large-diameter vertical deep hole is 100-120 mm, and the aperture of the empty hole is 60-80 mm.

3. The large-diameter deep hole mining method according to claim 1, which is safe, efficient and has a low mining-cutting ratio under broken ore and rock conditions, is characterized in that: In step S1, the cutting groove is arranged in the middle of the stope, runs through the entire stope in height, and has a width of 3 to 4 m along the mining direction of the ore body in the stope.

4. The large-diameter deep hole mining method according to claim 1, which is safe, efficient and has a low mining-cutting ratio under broken ore and rock conditions, is characterized in that: The mining field is mined in steps by using an alternate mining method. Before mining in a step mining field, several ore-exiting veins are constructed from the rock drilling tunnels in the adjacent two-step mining fields on both sides to the step mining field. The ore-exiting veins extend to the mining field boundary of the step mining field and are used for ore extraction in the step mining field.

5. The large-diameter deep hole mining method according to claim 1, which is safe, efficient and has a low mining-cutting ratio under broken ore and rock conditions, is characterized in that: In step S1, before the middle section is mined, the rock drilling chamber in the mining area is supported by joint support of anchor rods, anchor cables and metal mesh, and the surface of the rock drilling chamber is treated with shotcrete; the rock drilling tunnel at the bottom of the mining area in the lower middle section is pre-supported, and horizontal blast holes perpendicular to the side walls of the rock drilling tunnel are constructed at its bottom, and the horizontal blast holes are pre-blasted along the direction of the rock drilling tunnel by means of interval charging, so as to separate the mining area floor of the middle section from the bottom surrounding rock.

6. The large-diameter deep hole mining method according to claim 1, which is safe, efficient and has a low mining-cutting ratio under broken ore and rock conditions, is characterized in that: In step S2, the row spacing of the large-diameter vertical deep holes is 3.0-3.5 m, and the hole spacing of the downward inclined deep holes along the mining direction of the stope ore body is 3.0-3.5 m.

7. The large-diameter deep hole mining method according to claim 6, which is safe, efficient and low mining-cutting ratio under broken ore and rock conditions, is characterized in that: The aperture of the downward inclined deep hole is 100-120 mm. The downward inclined deep hole is inclined from the rock drilling chamber to the middle area of ​​the ore body in the mining area, and the angle with the vertical plane is 60°-70°, so as to ensure the blasting effect of the ore body inside the mining area and ensure the uniformity of the blasting block size.

8. The large-diameter deep hole mining method according to claim 1, which is safe, efficient and has a low mining-cutting ratio under broken ore and rock conditions, is characterized in that: In step S2, before mining, shallow horizontal holes are constructed in the columns between two rock drilling chambers of the stope, and explosives are charged and blasted together with the normal blasting row in step S3 to achieve the recovery of the columns.

9. The large-diameter deep hole mining method according to claim 4, which is safe, efficient and low mining-cutting ratio under broken ore and rock conditions, is characterized in that: The angle between the ore-exiting vein and the rock drilling tunnel is 40°-50°, and the spacing between the ore-exiting veins along the direction of the rock drilling tunnel is 10-12 m.

10. The large-diameter deep hole mining method according to claim 1, which is safe, efficient and has a low mining-to-cut ratio under broken ore and rock conditions, is characterized in that: Before the middle section is mined, the ore body is cut and cut, including a middle section transport tunnel located between the middle sections and along the direction of the ore body.

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