Non-pillar long-hole mining method in steeply inclined thick ore body with medium stable surrounding rock

Abstract

The application provides a mining method of middle-deep hole without a bottom pillar under the condition of an extremely inclined thick ore body and medium-stable surrounding rock, and relates to the field of underground mining of metal mines. The application first adopts a drift filling mining method to mine the drift stope in the central part of the upper sublevel ore body in the thickness of the ore body, and does not fill it temporarily, which is reserved as a drilling roadway; then a downward horizontal drift filling mining method is adopted to mine the lower sublevel ore body, and filling is completed to form an artificial false bottom, so as to ensure the stability of the roof in the process of mining the next sublevel middle-deep hole. On this basis, downward fan-shaped blast holes are drilled through the drilling roadway, and the ore in the ore room is transported out through the ore outlet roadway after the ore is blasted and dropped row by row, so that the mining of the middle sublevel ore body can be completed. Through the above method, the application can realize the mining of the middle-deep hole without a bottom pillar under the condition of the extremely inclined thick ore body and the medium-stable surrounding rock, which can ensure the safety and efficiency of the mining process, effectively improve the resource utilization rate, reduce the loss rate and the dilution rate of the ore, and improve the economic benefits.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of underground mining of metal mines, and particularly relates to a middle-deep hole mining method without a sill pillar under the condition of a medium-stable surrounding rock of a steeply inclined thick ore body. BACKGROUND

[0002] In the field of underground mining of metal mines, the loss rate and dilution rate of ore are important control indicators in the mining process. For the mining of underground gold mines, due to the scarcity and high value of the resource properties, it is particularly necessary to strictly control the loss rate and dilution rate of ore in the stoping process in order to achieve high economic benefits.

[0003] At present, when the steeply inclined thick and large medium-stable or more ore body of an underground gold mine is mined, the upward horizontal slicing drift mining method or the downward horizontal drift mining method is generally used. However, based on this mining method, the ore drawing process in the stope is similar to tunneling operation, and the operating personnel need to enter the stope for construction, and safety accidents occur frequently, and the production efficiency is low. Compared with the above-mentioned drift mining method, the mining method using middle-deep holes has the advantages of large production capacity and high construction safety, but the conventional middle-deep hole mining method needs to divide the ore room, and the inter-column, bottom column and top column need to be reserved between the ore rooms, and the inter-column, bottom column and top column have great difficulty in recovery in the later stoping process, and even cannot be recovered, causing resource waste. How to improve the resource utilization rate during middle-deep hole stoping and reduce the loss rate and dilution rate of ore is a problem to be solved at present.

[0004] In the prior art, the patent with publication number CN107939402A provides a mining method for steeply inclined thick ore body with medium or more stable rock in the stoping process. The patent blows out the ore by upwardly drilling shallow holes in the working space and downwardly drilling horizontal parallel middle-deep holes in the downwall direction, and part of the mined ore is temporarily left in the ore room as a buffer layer for protecting the bottom column and the upper wall. After the ore room is mined, a large amount of ore is drawn out to reduce the mixing of waste rock and improve the resource recovery rate. However, since the patent still needs to set the inter-column, top column and bottom column in the stope, and the inter-column, top column and upper middle section bottom column need to be recovered through a complex way after the ore is drawn out of the stope, the overall stoping process is relatively complex, the engineering quantity is large, and part of the bottom column cannot be recovered, and the resource utilization rate needs to be further improved.

[0005] Therefore, it is necessary to design an improved middle-deep hole mining method for the condition of a medium-stable surrounding rock of a steeply inclined thick ore body, in order to solve the above problems. SUMMARY

[0006] In view of the defects of the prior art, the present application aims to provide a non-pillar medium-length hole mining method under the condition of a medium-stable surrounding rock of a steeply inclined thick ore body, which can effectively improve the resource utilization rate, reduce the loss rate and dilution rate of the ore, and guarantee the economic benefits while ensuring the safety and efficiency of the mining process.

[0007] To achieve the above-mentioned purpose, the present application provides a non-pillar medium-length hole mining method under the condition of a medium-stable surrounding rock of a steeply inclined thick ore body, comprising the following steps:

[0008] S1: dividing the ore body into a plurality of mining sections along the vertical direction, each mining section comprising an upper layer ore body, a middle layer ore body and a lower layer ore body from top to bottom, and dividing the mining section into a plurality of ore rooms along the horizontal direction;

[0009] S2: using the drift filling mining method to mine the drift stope located in the central part of the upper layer ore body, and temporarily not filling it, so as to serve as a drilling roadway in the mining process of the middle layer ore body; using the horizontal drift filling mining method to mine the lower layer ore body and complete the filling;

[0010] S3: constructing downward fan-shaped blast holes in the drilling roadway, and after blasting and ore falling in each row, the ore in the ore room is transported out through the ore removal roadway;

[0011] S4: after the ore in the ore room is completely transported out, filling the ore room;

[0012] S5: mining the ore body in the upper layer ore body except the drilling roadway.

[0013] As a further improvement of the present application, in step S2, the horizontal drift filling mining method is a downward horizontal layer drift filling mining method, and after mining the lower layer ore body, high-strength cemented filling material is used for filling.

[0014] As a further improvement of the present application, before mining, the section transport roadway and the stope connecting roadway of each mining section need to be constructed.

[0015] As a further improvement of the present application, the section transport roadway corresponding to each mining section is arranged at the lower disc of the ore body, and the stope connecting roadway connects the section transport roadway and the mining section.

[0016] As a further improvement of the present application, the stope connecting roadway corresponding to each mining section comprises a first stope connecting roadway and a second stope connecting roadway; the first stope connecting roadway is constructed downward from the section transport roadway corresponding to the last mining section of the ore body to be mined, and the second stope connecting roadway is constructed horizontally from the section transport roadway corresponding to the mining section where the ore body to be mined is located.

[0017] As a further improvement of the present invention, the upper layer of ore body is located in the layer after the first stope connecting roadway enters the ore body, and the roof elevation of the upper layer of ore body is the same as the floor elevation of the segment transport roadway corresponding to the previous mining segment of the ore body; the lower layer of ore body is located in the layer where the second stope connecting roadway is located.

[0018] As a further improvement of the present invention, in step S3, a number of ore extraction roadways are arranged at intervals along the direction of the segmented transport roadway, and each ore extraction roadway is constructed by the segmented transport roadway in a direction perpendicular to the ore body.

[0019] As a further improvement of the present invention, in step S3, after the first ore-exit roadway on one side of the ore body reaches the hanging wall of the ore body, a cutting riser is constructed upward along the extension direction of the ore body, and the cutting riser is expanded into a cutting groove.

[0020] As a further improvement of the present invention, in step S4, when the filling height reaches the bottom plate height of the upper layer ore body, the filling is stopped, an artificial false bottom is constructed in the rock drilling tunnel, and filling is carried out.

[0021] As a further improvement of the present invention, in step S5, the downward horizontal layered approach filling mining method is used to mine and fill the ore body in the upper layered ore body except for the rock drilling roadway.

[0022] The beneficial effects of this invention are:

[0023] The present invention provides a method for bottomless deep-hole mining under moderately stable surrounding rock conditions in extremely inclined thick ore bodies. When mining the upper ore body using the horizontal layered approach and filling mining method, the approach stop located in the middle of the ore body thickness is mined first, but not filled immediately, and is reserved as a drilling roadway. When mining the lower ore body using the downward horizontal layered approach and filling mining method, each section is mined and filled sequentially during the mining operation to form an artificial false bottom, ensuring the stability of the roof during the next segment of deep-hole mining. Based on this, downward blast holes are constructed through the reserved drilling roadway to achieve bottomless deep-hole mining. Compared with traditional approach mining methods, the bottomless deep-hole mining method provided by the present invention has higher mining efficiency, better safety, and reduces the number of sections, effectively reducing the amount of preparation work. Compared with conventional deep-hole mining methods, the method provided by the present invention has higher resource utilization, can effectively reduce ore loss and dilution rates, and is conducive to improving economic benefits. Attached Figure Description

[0024] Fig. 1 This is a front view of the stope where the deep-hole mining method without bottom pillars is applied under moderately stable surrounding rock conditions in an extremely inclined thick ore body, as provided by the present invention.

[0025] Fig. 2 A side view of the stope in which the deep-hole mining method without bottom pillars is applied under moderately stable surrounding rock conditions in an extremely inclined thick ore body, as provided by the present invention.

[0026] Fig. 3 This is a top view of the stope where the deep-hole mining method without pillars is applied under moderately stable surrounding rock conditions in an extremely inclined thick ore body, as provided by the present invention.

[0027] Figure Labels

[0028] 1. Upper stratified ore body; 11. Drilling roadway; 2. Lower stratified ore body; 3. Sectional transport roadway; 41. First mining area connecting roadway; 42. Second mining area connecting roadway; 5. Ore extraction roadway; 6. Cutting groove; 7. Fan-shaped blast hole; 8. Ore; 9. Middle stratified ore body. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] It should also be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and / or processing steps closely related to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0031] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0032] This invention provides a method for deep-hole mining without bottom pillars under conditions of extremely inclined thick ore bodies and moderately stable surrounding rock, comprising the following steps:

[0033] S1: The ore body is divided into several mining sections along the vertical direction. Each mining section includes, from top to bottom, an upper layer ore body 1, a middle layer ore body, and a lower layer ore body 2. The mining section is then divided into several mining blocks along the horizontal direction.

[0034] S2: The access stop located in the middle of the thickness of the upper stratified ore body 1 is mined using the access method, and is not backfilled for the time being. It is used as the drilling roadway 11 in the mining process of the middle stratified ore body 9; the lower stratified ore body 2 is mined using the horizontal access backfilling mining method, and the backfilling is completed.

[0035] S3: Construct downward fan-shaped blast holes 7 in the rock drilling tunnel 11, and after detonating the ore in rows, transport the ore 8 in the ore chamber out through the ore outlet tunnel 5.

[0036] S4: After all the ore 8 in the mine has been transported out, the mine will be filled.

[0037] S5: Mining is carried out on the ore body in the upper layer ore body 1, excluding the rock drilling tunnel 11.

[0038] Through the above methods, the drilling roadway 11 reserved during the mining of the upper layered ore body 1 can be used to construct downward blast holes for medium-deep hole mining of the stope. After mining, the lower layered ore body 2 can form an artificial false bottom after backfilling, effectively ensuring the stability of the roof during the next section of medium-deep hole mining. Based on this, the present invention can achieve bottom-pillar-free medium-deep hole mining under moderately stable surrounding rock conditions in extremely inclined thick ore bodies. Compared with traditional access mining methods, it is safer and more efficient, reduces the number of sections, and effectively reduces the amount of preparation work. Compared with conventional medium-deep hole mining methods, it has a higher resource utilization rate, effectively reduces the loss rate and dilution rate of ore 8 and the need for top and bottom pillar mining operations, which is conducive to improving economic benefits.

[0039] Furthermore, the deep-hole mining method without bottom pillars provided by this invention is simple and easy to implement, requires less engineering work, and is applicable to the mining of gold mines in extremely inclined thick ore bodies under moderately stable surrounding rock conditions, thus possessing high practical application value. Here, an extremely inclined thick ore body refers to an ore body with a dip angle greater than 55° and a thickness greater than 20m.

[0040] The following detailed description of the deep-hole mining method without bottom pillars under moderately stable surrounding rock conditions in extremely inclined thick ore bodies provided by the present invention is based on specific embodiments.

[0041] Please refer to the following: Figs. 1-3 The schematic diagram of the stope structure shown illustrates the following steps in a preferred embodiment of the invention: The deep-hole mining method without pillars under conditions of extremely inclined thick ore bodies and moderately stable surrounding rock specifically includes the following steps:

[0042] S1, Ore Body Division

[0043] The ore body is divided vertically into mining sections of 16m each. Each mining section consists of an upper ore body 1, a middle ore body 9, and a lower ore body 2 from top to bottom. The vertical thickness of the upper ore body 1 and the lower ore body 2 is approximately 3 to 4m. The mining sections are also divided horizontally into ore blocks of 40m each.

[0044] It should be noted that in other embodiments of the present invention, the specific division parameters can be adjusted according to the actual ore body conditions and are not limited to the parameters described above.

[0045] S2, Approach and Recovery

[0046] Construct segmented transport roadways 3 at a certain distance from the ore body in the footwall of each mining section.

[0047] The first mining connecting roadway 41, which is constructed from the segment transport roadway 3 corresponding to the previous mining segment of the ore body, is made to descend into the ore body so that the roof elevation of the first mining connecting roadway 41 after entering the ore body is the same as the floor elevation of the segment connecting roadway. The ore body in which the first mining connecting roadway 41 enters the ore body is the upper layer ore body 1.

[0048] When mining the upper stratified ore body 1, the downward horizontal stratified approach mining method is preferred to facilitate the subsequent laying of a false bottom. When mining the upper stratified ore body 1, the approach stope located in the middle of the ore body thickness is mined first. After mining, it is not backfilled and is reserved as the drilling roadway 11 in the mining process of the middle stratified ore body 9, so as to facilitate the subsequent medium-deep hole mining process.

[0049] The second mining area connecting roadway 42 is constructed horizontally from the mining section corresponding to the mining section where the ore body is located. The ore body in the layer where the second mining area connecting roadway 42 is located is the lower layer ore body 2.

[0050] When mining the lower stratified ore body 2, the downward horizontal stratified approach backfilling mining method is also preferred, followed by backfilling after mining is completed. The backfill material used after mining the lower stratified ore body 2 is preferably a high-strength cemented backfill material with a cement-to-sand ratio of not less than 1:6. In other embodiments of the invention, the specific cement-to-sand ratio of the backfill material can be adjusted according to actual conditions, as long as the strength meets the requirements. This configuration allows it to act as an artificial false bottom, ensuring the stability of the roof during deep-hole mining in the next section.

[0051] S3, medium-deep hole mining

[0052] Multiple upward ore extraction roadways 5 are constructed perpendicular to the ore body and are set at intervals. They connect the stope and the ore extraction roadway 3 respectively, so as to transport the ore 8 that has collapsed in the stope to the ore extraction roadway 3.

[0053] Once the first ore-exit roadway 5 on one side of the stope reaches the hanging wall of the ore body, a cutting riser is constructed upwards along the extension direction of the ore body and gradually expanded into a cutting groove 6, which serves as a compensation space during the medium-deep hole mining process.

[0054] In the rock drilling roadway 11, downward fan-shaped blast holes 7 are constructed, and ore is detonated row by row. Then, the ore 8 that has collapsed in the stope is transported to the segmented transport roadway 3 through the ore exit roadway 5 to complete the medium-deep hole mining.

[0055] Using the above methods, the medium-deep hole mining process is simple and efficient, requires less engineering work, does not require the installation of bottom pillars, and has a high resource utilization rate.

[0056] S4, Filling

[0057] After the ore 8 from the intermediate stratum ore body 9 is transported, the ore extraction roadway 5 is sealed, thus completing the stope sealing. The filling pipeline is then suspended into the drilling roadway 11 of the stope, and filling is carried out through the drilling roadway 11. Conventional filling materials are used in this filling process; the specific lime-sand ratio can be selected according to the actual situation, as long as the strength requirements are met.

[0058] Filling is stopped when the filling height reaches the bottom plate height of the upper stratified ore body 1. An artificial false bottom is constructed in the drilling tunnel 11, followed by filling. High-strength cemented filling material is preferred. The cement-to-sand ratio of this high-strength cemented filling material is higher than that of the filling material in the stope, providing more stable support. In some embodiments of the invention, the cement-to-sand ratio of this high-strength cemented filling material is preferably 1:4; in other embodiments, the cement-to-sand ratio can be adjusted according to actual conditions, as long as the strength meets the requirements.

[0059] S5, the remaining part of the upper stratified ore body 1 will be mined.

[0060] The downward horizontal layered approach backfilling mining method is adopted to mine the ore body in the upper layer ore body 1 except for the rock drilling roadway 11. After the mining is completed, backfilling is carried out. The preferred backfilling material is a high-strength cemented backfilling material with a ash-sand ratio of 1:4.

[0061] Through the above methods, the method provided by the present invention can realize deep-hole mining without bottom pillars under the condition of moderately stable surrounding rock in extremely inclined thick ore bodies. Moreover, the overall mining process is simple and easy to carry out, with less engineering work. While ensuring the safety and efficiency of the mining process, it can also effectively improve the resource utilization rate.

[0062] In summary, this invention provides a method for deep-hole mining without pillars under moderately stable surrounding rock conditions in extremely inclined thick ore bodies, relating to the field of underground metal mining technology. This invention first employs a pass-through filling mining method to mine the pass-through stope located in the center of the ore body thickness of the upper stratum ore body 1, without immediately filling it, reserving it as a drilling roadway 11. Then, a downward horizontal pass-through filling mining method is used to mine the lower stratum ore body 2, completing the filling to form an artificial false bottom, ensuring the stability of the roof during the next segment of deep-hole mining. Based on this, this invention constructs downward fan-shaped blast holes 7 through the reserved drilling roadway 11, detonating and dropping ore row by row, and then transporting the ore 8 from the stope through the ore extraction roadway 5, thus completing the mining of the middle stratum ore body 9. Through the above method, this invention can achieve deep-hole mining without pillars under moderately stable surrounding rock conditions in extremely inclined thick ore bodies, effectively improving resource utilization while ensuring safety and efficiency in the mining process, reducing the loss and dilution rate of ore 8, and contributing to improved economic benefits.

[0063] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for deep-hole mining without bottom pillars under conditions of extremely inclined thick ore bodies and moderately stable surrounding rock, characterized in that, Includes the following steps: S1: The ore body is divided into several mining sections along the vertical direction. Each mining section includes an upper layer ore body, a middle layer ore body, and a lower layer ore body from top to bottom. The mining section is then divided into several mining blocks along the horizontal direction. S2: The access stop located in the middle of the ore body thickness in the upper stratum is mined using the access filling mining method, and is not filled temporarily, but is used as a drilling roadway in the mining process of the middle stratum; the lower stratum is mined using the horizontal access filling mining method, and the filling is completed. S3: Construct downward fan-shaped blast holes in the rock drilling tunnel, and after detonating the ore row by row, transport the ore in the ore chamber out through the ore outlet tunnel; S4: After all the ore in the mine has been removed, the mine will be filled. S5: Mining is carried out on the ore body in the upper stratum ore body, excluding the aforementioned drilling tunnel.

2. The deep-hole mining method without bottom pillars under moderately stable surrounding rock conditions in an extremely inclined thick ore body according to claim 1, characterized in that: In step S2, the horizontal access filling mining method is a downward horizontal stratified access filling mining method, in which high-strength cemented filling material is used for filling after the lower stratified ore body is mined.

3. The deep-hole mining method without bottom pillars under moderately stable surrounding rock conditions in an extremely inclined thick ore body according to claim 1, characterized in that: In step S2, before mining begins, it is also necessary to construct the segmented transport roadways for each mining section and the connecting roadways between the mining sites.

4. The deep-hole mining method without bottom pillars under moderately stable surrounding rock conditions in an extremely inclined thick ore body according to claim 3, characterized in that: Each mining segment has a corresponding haulage roadway located in the footwall of the ore body, and the stope connecting roadway connects the haulage roadway to the mining segment.

5. The deep-hole mining method without bottom pillars under moderately stable surrounding rock conditions in an extremely inclined thick ore body according to claim 4, characterized in that: The mining section corresponding to each mining segment includes a first mining section connecting roadway and a second mining section connecting roadway; the first mining section connecting roadway is constructed downward from the segment transport roadway corresponding to the previous mining segment of the ore body, and the second mining section connecting roadway is constructed horizontally from the segment transport roadway corresponding to the mining segment where the ore body is located.

6. The deep-hole mining method without bottom pillars under moderately stable surrounding rock conditions in an extremely inclined thick ore body according to claim 5, characterized in that: The upper stratified ore body is located in the stratum where the first stope connecting roadway enters the ore body, and the roof elevation of the upper stratified ore body is the same as the floor elevation of the segment transport roadway corresponding to the previous mining segment of the ore body; the lower stratified ore body is located in the stratum where the second stope connecting roadway is located.

7. The deep-hole mining method without bottom pillars under moderately stable surrounding rock conditions in an extremely inclined thick ore body according to claim 4, characterized in that: In step S3, several ore extraction roadways are arranged at intervals along the direction of the segmented transport roadway, and each ore extraction roadway is constructed by the segmented transport roadway in a direction perpendicular to the ore body.

8. The deep-hole mining method without bottom pillars under moderately stable surrounding rock conditions in an extremely inclined thick ore body according to claim 7, characterized in that: In step S3, after the first ore-exit roadway on one side of the ore body reaches the hanging wall of the ore body, a cutting riser is constructed upward along the extension direction of the ore body, and the cutting riser is expanded into a cutting groove.

9. The deep-hole mining method without bottom pillars under moderately stable surrounding rock conditions in an extremely inclined thick ore body according to claim 1, characterized in that: In step S4, when the filling height reaches the bottom plate height of the upper layer ore body, the filling is stopped; then, an artificial false bottom is constructed in the rock drilling tunnel and filled.

10. The deep-hole mining method without bottom pillars under moderately stable surrounding rock conditions in an extremely inclined thick ore body according to claim 1, characterized in that: In step S5, the downward horizontal layered approach backfilling mining method is used to mine and backfill the ore body in the upper layered ore body, excluding the rock drilling roadway.

Images