A method for benching and trenching in an open pit mine by blasting from both ends

Abstract

The application discloses a kind of open-pit mine two-end blasting layering ditching methods, including perforation, blasting, shovel loading and ditching operation, the ditching method includes the following steps: first, the ditching area is divided into five blast areas, the initial blast area depth is maximum and sets drainage pit;Perforation and blasting operation are carried out in order from both sides to the middle, then temporary drainage pit and access ditch are excavated;Shovel loading and ditching operation are carried out layer by layer, when the current level of shovel loading and ditching operation is completed, the next layer operation is continued, which can ensure that the depth of the drainage pit is always the lowest, reducing the impact of mine water on construction.The open-pit mine two-end blasting layering ditching method has the advantages of improving ditching efficiency, shortening construction time, improving new level of driving speed, timely releasing lower ore quantity, etc., which can maximize the efficiency of open-pit mine ditching.

Description

Technical Field

[0001] This invention relates to the field of blasting operations in open-pit mines, and more specifically to a method for layered trenching by blasting at both ends of an open-pit mine. Background Technology

[0002] Open-pit mine new level preparation mainly refers to expanding the lower working space, releasing lower ore reserves, maintaining the balance of secondary ore reserves in the stope, improving the operating efficiency of machinery and equipment, and ensuring high and stable production to maximize economic benefits by excavating an access trench from the current level and opening a passage connecting to the next level. To ensure rapid excavation of the new level, the width of the access trench is usually chosen to be minimal, only requiring sufficient space for equipment operation. Therefore, the working space is relatively narrow, and the number of equipment is limited, resulting in a relatively slow excavation speed.

[0003] Currently, in open-pit mining, the unidirectional trenching method is commonly used. The specific construction process is as follows: blasting operations are completed in one blasting zone first, then mining equipment is used to enter that zone for loading and trenching. After trenching in that zone is completed, blasting operations continue in the next blasting zone along the same direction, and trenching continues in that zone until the trenching is complete. Using this method, it is impossible to put all mining equipment into production, resulting in low trenching efficiency, slow bench descent, and impacting the mine's encounter time and economic benefits. In open-pit mines with large water inflows, as the mining depth gradually increases and enters the depression or deep depression mining stage, the mining operations at the lower level will be significantly affected by the water inflow, especially when the new level reaches the open-pit mine's static water level. Summary of the Invention

[0004] To address the technical problems in the background art, this invention provides a method for layered trenching via blasting at both ends of an open-pit mine. Based on existing machinery and mining conditions, this method can shorten trenching time, improve construction efficiency, and promptly release the underlying ore volume. It also reduces the impact of mine water inflow on construction, lowers construction difficulty, and ensures stable mine production. This solves the problems of slow progress, low trenching rate, and susceptibility to mine water inflow during new-level mine excavation.

[0005] The technical solution of this invention to solve the technical problem is as follows:

[0006] This invention discloses a method for layered trenching in open-pit mines using blasting at both ends, comprising drilling, blasting, loading, and trenching operations. The trenching area is divided into five blasting zones from both ends towards the middle: Zone 1, Zone 2, Zone 3, Zone 4, and Zone 5. The drilling depth of Zone 1 (Blast Zone 1) is greater than that of the other blasting zones. A drainage pit is set inside Zone 1, and loading is carried out in three layers. The other blasting zones are divided into two stages for trenching operations. In each stage, a first-stage access trench and a second-stage access trench are excavated sequentially from the top of Zone 2 towards the bottom of the first and second layers of Zone 1. The specific steps are as follows:

[0007] S1. First, drill and blast in the No. 1 and No. 2 blasting areas, then drill and blast in the No. 3 and No. 4 blasting areas.

[0008] S2. In Artillery Area 1, shovel loading operations are carried out to excavate the first-stage temporary drainage pit. Then, in Artillery Areas 2 and 4, trenching operations are started to excavate the first half of the first-stage access trench.

[0009] S3. Drilling and blasting are carried out in the No. 5 blasting area, followed by shoveling and trenching operations in the No. 1, No. 3 and No. 5 blasting areas to complete the first stage of trenching operations.

[0010] S4. Carry out shoveling operations in the No. 1 blasting area to dig out the second-stage temporary drainage pit;

[0011] S5. Carry out trenching operations in the order of No. 2, No. 4, No. 5 and No. 3, remove the intermediate ore rock between the first-stage access trench and the second-stage access trench, and complete the excavation operation of the second-stage access trench.

[0012] S6. Carry out shoveling operations in the No. 1 blasting area, dig out the three-stage temporary drainage pit, and complete the trenching operation.

[0013] Furthermore, the drilling depth of the No. 1 blasting zone is 20m, the drilling depth of the No. 2, No. 3, No. 4 and No. 5 blasting zones is 14m, and the step height is 12m.

[0014] Furthermore, the No. 1 gun area is divided into three layers, each 6m deep, and the first-stage temporary drainage pit, the second-stage temporary drainage pit, and the third-stage temporary drainage pit are all 6m deep.

[0015] Furthermore, the slopes of both the first-stage and second-stage entry / exit ditches are less than 8%.

[0016] Furthermore, when excavating and loading the ore around the first-stage or second-stage access trench, the accumulated water in the first-stage or second-stage temporary drainage pit should be pumped out before construction.

[0017] Compared with the prior art, the open-pit mine blasting layered trenching method described in this invention has the following beneficial effects:

[0018] 1. The open-pit mine blasting layered trenching method described in this invention does not require special facilities or conditions and can be carried out based on the existing machinery and equipment and mining conditions of the open-pit mine. It can shorten the trenching time, improve construction efficiency, release the lower ore volume in a timely manner, reduce the impact of mine water inflow on construction, reduce construction difficulty, ensure stable mine production, and solve the problems of slow progress, low trenching rate and influence of mine water inflow in new level mining.

[0019] 2. The open-pit mine blasting layered trenching method described in this invention is applicable to all types of mines, especially in cases where the water inflow is large, the ore body is deeply buried, and the initial stripping ratio is large. Attached Figure Description

[0020] Figure 1 This is a top-view schematic diagram of a method for layered trenching by blasting at both ends of an open-pit mine according to the present invention;

[0021] Figure 2 This is a schematic elevation cross-sectional view of a method for layered trenching by blasting at both ends of an open-pit mine, according to the present invention.

[0022] Figure 3 yes Figure 2 A schematic diagram illustrating the commencement of trenching operations and the first phase of drainage pit construction;

[0023] Figure 4 yes Figure 2 A schematic diagram of the first-stage entry and exit ditch and the second-stage drainage pit operation;

[0024] Figure 5 yes Figure 2 A schematic diagram of the two-stage entry and exit trench and final drainage pit operation;

[0025] In the diagram: 1. Artillery Zone 1; 2. Artillery Zone 2; 3. Artillery Zone 3; 4. Artillery Zone 4; 5. Artillery Zone 5; 6. Drainage pit; 7. Intermediate ore rock; 8. First-stage access ditch; 9. Second-stage access ditch; 10. Bench base; 11. Upper ore rock in Artillery Zone 1; 12. Middle ore rock in Artillery Zone 1; 13. Lower ore rock in Artillery Zone 1; 21. Ore rock above the first-stage access ditch in Artillery Zone 2; 31. Ore rock above the first-stage access ditch in Artillery Zone 3; 41. Ore rock above the first-stage access ditch in Artillery Zone 4; 51. Ore rock above the first-stage access ditch in Artillery Zone 5; 61. First-stage temporary drainage pit; 62. Second-stage temporary drainage pit; 63. Third-stage temporary drainage pit. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art to which this disclosure pertains. The terms "upper," "lower," "left," "right," "front," and "rear" used in the present patent application specification and claims are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship also changes accordingly. Any aspects not detailed in this invention are well-known techniques to those skilled in the art.

[0027] Please see Figure 1-5 This invention discloses a method for layered trenching via blasting at both ends of an open-pit mine, comprising drilling, blasting, loading, and trenching operations. Figure 1 As shown, the trenching area is divided into five sections from both ends towards the middle: Section 1 (blasting zone 1), Section 2 (blasting zone 2), Section 3 (blasting zone 3), Section 4 (blasting zone 4), and Section 5 (blasting zone 5). The drilling depth of Section 1 (blasting zone 1) is greater than that of the other sections. A drainage pit 6 is set inside Section 1 (blasting zone 1). The trenching operation is carried out in three layers: the upper layer 11, the middle layer 12, and the lower layer 13 of the ore in Section 1 (blasting zone 1). The other sections are divided into two stages for trenching operations. The two stages are respectively digging the first-stage access trench 8 and the second-stage access trench 9 from the top of Section 2 (blasting zone 2) towards the bottom of the first and second layers of Section 1 (blasting zone 1). The specific steps are as follows:

[0028] S1. First, drilling and blasting are carried out in blasting area 1 and blasting area 2. The drilling depth in blasting area 1 is 20m and the drilling depth in blasting area 2 is 14m. Then, drilling and blasting are carried out in blasting area 3 and blasting area 4. The drilling depth is 14m and the step height is set to 12m.

[0029] S2. In Artillery Zone 1, shovel and load operations are carried out to excavate a temporary drainage pit 61 (stage 1) with a depth of 6m. Then, trenching operations begin in Artillery Zones 2 and 4, shoveling and loading the ore 21 above the stage 1 access trench in Artillery Zone 2 and the ore 41 above the stage 1 access trench in Artillery Zone 4, forming the first half of the stage 1 access trench 8.

[0030] S3. Drilling and blasting are carried out in blasting area 5, with a drilling depth of 14m. Then, shoveling and trenching operations are carried out in blasting area 1, blasting area 3, and blasting area 5. The ore and rock 51 above the first stage access trench of blasting area 5, the ore and rock 31 above the first stage access trench of blasting area 3, and the upper layer ore and rock 11 of blasting area 1 are shoveled to complete the excavation of the first stage access trench 8, so that the lowest point of the first stage access trench 8 is 6m lower than the previous step. At this time, the horizontal plane of blasting area 1 is 6m lower than the previous step.

[0031] S4. In the No. 1 blasting area 1, the middle layer of ore 12 in the No. 1 blasting area is shoveled and loaded, and the second-stage temporary drainage pit 62 of the drainage pit 6 is dug out. The depth of the second-stage temporary drainage pit 62 is 6m.

[0032] S5. Following the order of No. 2 blasting area 2, No. 4 blasting area 4, No. 5 blasting area 5 and No. 3 blasting area 3, the trenching operation is carried out in sequence. The intermediate rock 7 between the first stage access trench 8 and the second stage access trench 9 is removed, and the excavation operation of the second stage access trench 9 is completed, so that the lowest point of the second stage access trench 9 is 12m lower than the previous step.

[0033] S6. In the No. 1 blasting area 1, the lower layer of ore 13 in the No. 1 blasting area is shoveled and loaded, and the three-stage temporary drainage pit 63 of the drainage pit 6 is dug out. The depth of the three-stage temporary drainage pit 63 is 6m, and the trenching operation is completed.

[0034] In this embodiment, the slopes of the first-stage entry / exit ditch 8 and the second-stage entry / exit ditch 9 are both less than 8%, which facilitates construction.

[0035] In this embodiment, in order to ensure that the mine water inflow does not affect production, the No. 1 blasting area 1 and the drainage pit 6 within it are always kept at the deepest point during the construction process. When excavating and loading the ore around the first-stage access ditch 8 or the second-stage access ditch 9, the water in the first-stage temporary drainage pit 61 or the second-stage temporary drainage pit 62 is pumped out before construction.

[0036] This invention enables the excavation of drainage pits and access trenches for the next stage of open-pit mines to be completed in a relatively short time. According to the above examples, under normal circumstances, the entire excavation operation can be completed within twenty days, thereby greatly improving construction efficiency and increasing mine production benefits.

Claims

1. A method for layered trenching via blasting at both ends of an open-pit mine, comprising drilling, blasting, loading, and trenching operations, characterized in that, The trenching area is divided into five sections from both ends toward the middle: Section 1 (1), Section 2 (2), Section 3 (3), Section 4 (4), and Section 5 (5). The drilling depth of Section 1 (1) is greater than that of the other sections. A drainage pit (6) is set up inside Section 1 (1). The trenching operation is carried out in three layers. The other sections are divided into two stages for trenching. The two stages are respectively excavated from the top of Section 2 (2) toward the bottom of the first layer and the bottom of the second layer of Section 1 (1) to form a first-stage access trench (8) and a second-stage access trench (9). The specific steps are as follows: S1. First, drilling and blasting are carried out in the No. 1 blasting area (1) and the No. 2 blasting area (2), and then drilling and blasting are carried out in the No. 3 blasting area (3) and the No. 4 blasting area (4); S2. In the No. 1 blasting area (1), a shovel operation is carried out to dig out a temporary drainage pit (61) of the first stage of the drainage pit (6). Then, in the No. 2 blasting area (2) and the No. 4 blasting area (4), trenching operations are started to dig out the first half of the first stage access trench (8). S3. Drilling and blasting are carried out in the No. 5 blasting area (5), and then shoveling and trenching operations are carried out in the No. 1 blasting area (1), the No. 3 blasting area (3) and the No. 5 blasting area (5) to complete the first stage of the tunneling operation in the trench (8). S4. In the No. 1 blasting area (1), a second-stage temporary drainage pit (62) is dug out to form the drainage pit (6); S5. Following the order of No. 2 blasting area (2), No. 4 blasting area (4), No. 5 blasting area (5) and No. 3 blasting area (3), the trenching operation is carried out in sequence, and the intermediate ore rock (7) between the first stage entry and exit trench (8) and the second stage entry and exit trench (9) is removed to complete the excavation operation of the second stage entry and exit trench (9). S6. In the No. 1 blasting area (1), a three-stage temporary drainage pit (63) of the drainage pit (6) is dug out to complete the trenching operation.

2. The method for layered trenching by blasting at both ends of an open-pit mine according to claim 1, characterized in that: The drilling depth of the No. 1 blasting zone (1) is 20m, and the drilling depth of the No. 2 blasting zone (2), No. 3 blasting zone (3), No. 4 blasting zone (4) and No. 5 blasting zone (5) is 14m, with a step height of 12m.

3. The method for layered trenching by blasting at both ends of an open-pit mine according to claim 2, characterized in that: The No. 1 artillery area (1) is divided into three layers, each 6m deep. The first-stage temporary drainage pit (61), the second-stage temporary drainage pit (62), and the third-stage temporary drainage pit (63) of the drainage pit (6) are all 6m deep.

4. The method for layered trenching by blasting at both ends of an open-pit mine according to claim 1, characterized in that: The slopes of the first-stage entry / exit ditch (8) and the second-stage entry / exit ditch (9) are both less than 8%.

5. The method for layered trenching by blasting at both ends of an open-pit mine according to claim 1, characterized in that: When excavating and loading the ore around the first-stage access trench (8) or the second-stage access trench (9), the water in the first-stage temporary drainage pit (61) or the second-stage temporary drainage pit (62) should be pumped out before construction.

Images