A mining method for fully separating ore bodies under a mined-out subsidence area

Abstract

The present application discloses a method for fully separating the mining of ore bodies under a mined-out subsidence area, which includes mining by sublevel caving method and filling the subsidence area with paste. The underground stope is demarcated with the ore body boundary within the influence range of the subsidence pit as the boundary. Each subsidence pit corresponds to an underground stope one by one, and mining and filling are carried out in sequence according to the stope. The space connection between the filling body and the stoping face is blocked by the waste rock loose body in the subsidence area with a thickness not less than the critical caving loose body column thickness. The subsidence pit is filled with cement, and the stope adopts the technology of diversion ore drawing to guide the waste rock hopper containing waste rock and fine tailings to the footwall side, creating good ore-rock contact surface conditions for the next sublevel. The present application is applicable to steeply inclined ore bodies, realizes the separation of mining and filling spaces, can avoid the mutual interference of mining and filling processes, thus greatly improving the mining and filling efficiency and achieving safe and efficient mining effects.

Description

Technical Field

[0001] This application relates to the technical field of underground mining, and particularly to a mining method for fully separating ore bodies under a mined-out subsidence area. Background Art

[0002] In China, for medium-thick deposits to thick ore bodies with gently inclined strata, caving methods and open stoping methods are used for shallow mining, resulting in a series of collapse pits on the surface. When changing to filling methods for mining such deposits at the bottom, the conventional filling mining process and filling process are complex, with high labor intensity, low production efficiency, and high costs. Filling and mining affect each other. If the mechanization of stoping operations cannot be properly solved, both production efficiency and production capacity are relatively low. To achieve safe and efficient mining, there is an urgent need for a mining method that can fully separate ore bodies under a mined-out subsidence area. Summary of the Invention

[0003] To solve the above problems, the embodiments of this application provide a mining method for fully separating ore bodies under a mined-out subsidence area, which is applicable to steeply inclined ore bodies and can achieve safe and efficient mining effects. The technical solutions are as follows:

[0004] This application provides a mining method for fully separating ore bodies under a mined-out subsidence area, including mining by sublevel caving method and filling the subsidence area with paste. The underground stope is divided with the ore body boundary affected by the collapse pit as the boundary. Each collapse pit corresponds to an underground stope one by one, and mining and filling are carried out in sequence according to the stope. The space connection between the filling body and the stoping face is blocked by waste rock loose bodies in the subsidence area with a thickness not less than the critical caving loose body column thickness. The collapse pit is filled with cemented filling, and the stope adopts the technology of diversion ore drawing, guiding the waste rock and fine tailings waste rock funnels to the footwall side to create good ore-rock contact surface conditions for the next sublevel.

[0005] For example, in the mining method for fully separating ore bodies under a mined-out subsidence area provided in one embodiment, the subsidence area is filled with paste, the filling location is moved up to the surface, and the collapse pit is filled from the surface. The filling body is used to squeeze the side wall of the collapse pit to control the further expansion of the collapse range.

[0006] For example, in the mining method for fully separating ore bodies under a mined-out subsidence area provided in one embodiment, the ore is mined underground by the sublevel caving method with large structural parameters, and the mined-out area formed after mining is filled with waste rock loose bodies moving down in the collapse pit.

[0007] For example, in the mining method for fully separating ore bodies under a mined-out subsidence area provided in one embodiment, mining and filling are carried out in sequence according to the stope. After the stoping of each stope is completed, the collapse pit is filled. After one month of solidification of the filling, underground mining is carried out again.

[0008] For example, in the method for fully separating the mining of ore bodies under the mining subsidence area provided in one embodiment, a geotextile is laid before backfilling to block cracks and prevent the backfill slurry from flowing downward through the cracks.

[0009] For example, in the method for fully separating the mining of ore bodies under the mining subsidence area provided in one embodiment, the thickness of the waste rock loose body in the subsidence area is not less than 100 - 150 m, so as to keep the side wall of the subsidence pit relatively stable and ensure the safety of the operation of laying the geotextile.

[0010] For example, in the method for fully separating the mining of ore bodies under the mining subsidence area provided in one embodiment, after the cemented filling body is dislocated and fragmented, the broken blocks are allowed to drill to a certain depth, and the thickness of the normal overburden layer below it is greater than the critical caving loose body column thickness, so as to ensure the normal mining conditions of the caving method stope.

[0011] For example, in the method for fully separating the mining of ore bodies under the mining subsidence area provided in one embodiment, when ore is drawn from the stope, no ore is drawn from the upper wall side ore drawpoint, and ore is drawn from the lowest wall side ore drawpoint, guiding the waste rock and fine tailings waste rock funnels containing waste rock to the lower wall side, while preventing debris flow.

[0012] The beneficial effects brought by a method for fully separating the mining of ore bodies under the mining subsidence area provided in some embodiments of the present application are as follows: The present application integrates the innovation of the sublevel caving method and the filling technology. The caving method has the technological advantages of safety, high efficiency, less material consumption, and low carbon emissions per unit of ore mined. However, the caving of the goaf causes surface subsidence. The present application also treats the subsidence pit. After backfilling, the subsidence pit is filled with surface floating soil, and the natural landform can be restored after greening, safely and efficiently protecting the surface environment. It realizes the safe and efficient mining of ore bodies using the caving method. At the same time, filling the subsidence pit from the surface is equivalent to filling the mined-out area removed from the surface, achieving the purpose of using the filling body to protect the surface from further expanding the subsidence range. The separation of the mining and filling spaces achieved thereby can avoid the mutual interference between the mining and filling processes, thus greatly improving the mining and filling efficiency and achieving safe and efficient mining results. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present specification or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0014] Figure 1 It is a schematic diagram of the fully separated mining stope structure. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0015] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the protection scope of the present application.

[0016] Unless otherwise defined, the technical terms or scientific terms used in this disclosure shall have the ordinary meanings understood by those of ordinary skill in the art to which this disclosure pertains. The "first", "second" and similar terms used in this disclosure do not denote any order, quantity or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or objects appearing before this term cover the elements or objects listed after this term and their equivalents, without excluding other elements or objects. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections. The terms such as "upper", "lower", "left", "right" are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0017] The present application provides a method for fully separating the mining of ore bodies under a mining-induced collapse area, which is applicable to steeply inclined ore bodies, such as Figure 1 as shown, including mining by sublevel caving method and paste filling the collapse area. The underground stope is divided with the ore body boundary affected by the collapse pit as the boundary. Each collapse pit corresponds to an underground stope one by one, and mining and filling are carried out in sequence according to the stope. The space connection between the filling body and the stoping face is blocked by the waste rock loose body in the collapse area with a thickness not less than the critical caving loose body column thickness. The collapse pit is filled with cement, and the stope adopts the diversion ore drawing technology to guide the waste rock and fine tailings waste rock funnels to the footwall side to create good ore-rock contact surface conditions for the lower sublevel, so as to control the ore loss and dilution of the footwall ore.

[0018] The method for fully separating the mining of ore bodies under the mining-induced collapse area of the present application is essentially an integrated innovation of the sublevel caving method and the filling technology. The caving method has the technological advantages of safety, high efficiency, less material consumption and low carbon emissions per unit of ore mined. However, the caving of the goaf causes surface collapse. The present application also treats the collapse pit at the same time. After the filling is completed, the collapse pit is filled with surface floating soil, and the natural landform can be restored after greening, safely and efficiently protecting the surface environment. Figure 1 The fully separated stope structure shown completely realizes the safe and efficient mining of ore bodies by using the caving method. At the same time, filling the collapse pit from the surface is equivalent to filling and removing the goaf on the surface, achieving the purpose of protecting the surface with the filling body from further expanding the collapse range. And the separation of the mining and filling space achieved thereby can avoid the mutual interference of the mining and filling processes, thus greatly improving the mining and filling efficiency and achieving safe and efficient mining effects.

[0019] For example, in the method for fully separating the mining of ore bodies under the mining subsidence area provided in one embodiment, the subsidence area is filled with paste, the filling location is moved up to the ground surface, the subsidence pit is filled from the ground surface, and the side wall of the subsidence pit is squeezed by the filling body to control the further expansion of the subsidence range.

[0020] For example, in the method for fully separating the mining of ore bodies under the mining subsidence area provided in one embodiment, the ore is safely and efficiently mined underground by the sublevel caving method with large structural parameters, and the mined-out area formed after mining is filled by the downward movement of the waste rock debris in the subsidence pit.

[0021] For example, in the method for fully separating the mining of ore bodies under the mining subsidence area provided in one embodiment, mining and filling are carried out in sequence according to the stope. After the mining of each stope is completed, the subsidence pit is filled. After the filling solidifies for one month, underground mining is carried out again.

[0022] For example, in the method for fully separating the mining of ore bodies under the mining subsidence area provided in one embodiment, a geotextile is laid before filling to block the cracks and surface cracks to prevent the filling slurry from pouring down through the cracks.

[0023] For example, in the method for fully separating the mining of ore bodies under the mining subsidence area provided in one embodiment, the thickness of the waste rock debris in the subsidence area is generally not less than 100 ～ 150 m, so as to keep the side wall of the subsidence pit relatively stable and ensure the safety of the operation of laying the geotextile.

[0024] For example, in the method for fully separating the mining of ore bodies under the mining subsidence area provided in one embodiment, after the cemented filling body is dislocated and fragmented, the broken blocks are allowed to drill a certain depth, and the thickness of the normal overburden layer below it is greater than the critical caving debris column thickness, so as to ensure the normal stoping conditions of the sublevel caving stope.

[0025] For example, in the method for fully separating the mining of ore bodies under the mining subsidence area provided in one embodiment, when ore is drawn from the stope, no ore is drawn from the upper wall side ore drawpoint, and ore is only drawn from the lowest wall side ore drawpoint. The waste rock and fine tailings waste rock funnels are guided to the lower wall side, and at the same time, debris flow is prevented.

[0026] Although the embodiments of the present application have been disclosed as above, they are not limited to only the applications listed in the specification and the embodiments. It can be fully applied to various fields suitable for the present application. For those familiar with the field, additional modifications can be easily achieved. Therefore, without departing from the general concept defined by the claims and the equivalent scope, the present application is not limited to the specific details and the illustrated examples here.

Claims

1. A mining method for fully separating ore bodies under a mining subsidence area, characterized in that, It includes mining by sublevel caving method and paste filling in the subsidence area. The underground stope is demarcated with the ore body boundary affected by the subsidence pit as the boundary. Each subsidence pit corresponds to an underground stope one by one, and mining and filling are carried out in sequence according to the stope. The spatial connection between the filling body and the stoping face is cut off by the waste rock loose body in the subsidence area with a thickness not less than that of the critical caving loose body column. The subsidence pit is filled with cemented paste, and the stope adopts the technology of diversion ore drawing. When ore is drawn from the stope, the ore outlet on the hanging wall side does not draw ore, and ore is drawn from the lowest footwall ore outlet. The waste rock and fine tailings funnels are guided to the footwall side to create good ore-rock contact surface conditions for the next sublevel and prevent debris flow at the same time. Among them, the subsidence area is filled with paste, the filling location is moved up to the ground surface, the subsidence pit is filled from the ground surface, and the side wall of the subsidence pit is squeezed by the filling body to control the further expansion of the subsidence range. Ore is mined underground by the sublevel caving method with large structural parameters, and the mined-out area formed after mining is filled by the downward movement of the waste rock loose body in the subsidence pit. Mining and filling are carried out in sequence according to the stope. After the stoping of each stope is completed, the subsidence pit is filled. After one month of solidification of the filling, underground mining is carried out again.

2. The fully separated mining method for ore bodies under the goaf caused by mining as claimed in claim 1, wherein Before filling, a geotextile is laid to block the cracks to prevent the filling slurry from flowing down through the cracks.

3. The method for fully separating mining of ore bodies under the goaf caused by mining according to claim 2, characterized in that, The thickness of the waste rock loose body in the subsidence area is not less than 100 - 150 m, so as to keep the side wall of the subsidence pit relatively stable and ensure the safety of the operation of laying the geotextile.

4. The method for fully separating mining of ore bodies under the goaf caused by mining according to claim 3, characterized in that, After the cemented filling body is dislocated and fragmented, the broken blocks are allowed to drill a certain depth, and the thickness of the normal overburden layer below it is greater than that of the critical caving loose body column, so as to ensure the normal stoping conditions of the caving stope.

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