Mining method for recovering hanging wall ore body through external expansion of surface mine
By opening open sections of trenches and trapezoidal rock walls on the steep slopes of the open-pit mines, the problem of rolling stones threatening the production safety of the lower part is solved, and safe and efficient production of the open-pit mines is achieved.
Patent Information
- Application Number
- CN202411712927.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-27
- Publication Date
- 2025-01-07
AI Technical Summary
In open-pit mines, rolling stones caused by high steep slope expansion operations threaten the safety of lower production equipment and personnel, and the existing technology is difficult to effectively clean pumice stones, affecting production safety.
A section of the ditches with a width of no less than 20m are created on the high and steep slope, and a trapezoidal rock wall is formed on the slope side, for lateral blasting and expansion shoveling and mining, and then return to the slope side after the inner ore is recovered. The trapezoidal rock wall is cleaned, the pumice stone on the slope is formed into a working platform with a width of no less than 40m, and repeat this process until the mining is completed.
Effectively prevent rolling stones from threatening lower production safety, simplify operating processes, improve production efficiency, and ensure safe and efficient production of mines.
Smart Images
Figure CN119266826A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a mining method, in particular to a mining method for recovering hanging ore bodies in an open-pit mine, and belongs to the technical field of open-pit mining. Background Art
[0002] At present, about 90% of my country's large open-pit iron ore mines have been converted to deep pit open-pit mining, and the production capacity has gradually entered a period of decline. However, with the advancement of mineral processing technology, the resource recovery rate has been improved, and the economically reasonable stripping ratio used in the original open-pit mining boundary delineation will increase, so that most open-pit mines have the conditions to expand and extend to recover the hanging ore body to make up for the decline in production capacity. Due to the restrictions of the open-pit top-down layered mining method, if the mine can achieve non-stop production and expansion transition to maintain production, the expansion and extension of the wall will have a spatial relationship with the simultaneous operation of the upper and lower parts, the initial stripping strip trenching operation of the upper high and steep slope expansion, and the rolling stones generated by blasting and shoveling disturbance threaten the safety of the lower production equipment and personnel. In addition, most of the accumulated slag produced as the steep slope is expanded and descended is stored on the slope and platform between the expansion operation and the production operation. Since the height of a single step in a large open-pit mine is generally more than 15m, and the maximum digging height of existing long-arm excavator equipment is about 15m, considering the inclination factor of the slope angle, it is actually only possible to clean up some of the floating stones on the slope surface, and it is difficult to clean up the slag accumulated on the safety platform. Affected by the vibration of the upper horizontal expansion blasting, floating stones are prone to rolling down, which also threatens the safety of the lower production. Summary of the invention
[0003] The technical problem to be solved by the present invention is to provide a mining method for expanding and recovering hanging ore bodies in open-pit mines, which can prevent rolling stones from threatening normal safe production at the bottom and does not require stopping production for transitional expansion.
[0004] The technical solution adopted to solve the above technical problems is: a mining method for expanding and recovering the hanging wall ore body in an open-pit mine, wherein the mining method first opens an open section ditch with a width of not less than 20m along the length direction of the slope on the high and steep slope according to the expansion boundary in the open-pit mine, and forms a trapezoidal rock wall on the side facing the slope, and then performs lateral blasting and wall expansion and shoveling mining operations on the ore rock on the non-slope side in the open section ditch, and after the mining and recovery of the inner ore is completed, the trapezoidal rock wall on the slope side is mined, and after the trapezoidal rock wall is mined, the pumice and rock on the slope surface are cleaned to form a working platform with a width of not less than 40m; then, based on the working platform, the ore rock on the inner side of the working platform is continuously subjected to lateral blasting and wall expansion and shoveling mining operations, and the aforementioned steps are repeated on the side of the working platform facing the slope to form a working platform with a width of not less than 40m in the next section, and so on until the mining of all the open-pit mine expansion and wall recovery ore bodies that need to be mined is completed.
[0005] Furthermore, the width of the top edge of each trapezoidal rock wall formed by the trenching is not less than 5m.
[0006] The preferred embodiment of the above scheme is that, when digging a trench section, an excavator is first used to dig a double-wall trench, and then blasting and mining are performed in the double-wall trench to form a trench section with a width of not less than 20m and an outer trapezoidal rock wall.
[0007] Furthermore, the height of the ore rock mined by each working platform does not exceed 7.5m per section, and the height of the ore rock formed by two adjacent working platforms does not exceed 15m per layer.
[0008] The preferred method of the above scheme is to first design the mining of the open-pit mine expansion and recovery hanging wall ore body based on the exploration data before mining, form a layer of ore rock with a height of no more than 15m according to the single step height, and then divide the layer into at least two sections with a single section height of no more than 7.5m, and then mark the open-pit mine expansion and recovery hanging wall ore body as the basis for tunneling mining and / or blasting mining.
[0009] Furthermore, along the length direction of the working platform, the mining areas sequentially arranged on each working platform may be one or more, and the distance between two adjacent mining areas shall not be less than 100m; the mining layers and / or mining sections recovered and set into the open-pit mine rock body along the width direction of the slope may be one or more.
[0010] The preferred embodiment of the above scheme is that after digging the double-walled trench, the slope angle of one side of the trench wall formed by the sidewall expansion mining operation using lateral blasting and wall expansion shoveling is ≤75°.
[0011] Furthermore, lateral blasting and wall expansion and shoveling are also used during the mining of the trapezoidal rock wall.
[0012] The preferred embodiment of the above scheme is that after the trapezoidal rock wall is mined, the pumice and rocks on the slope surface are cleaned by an excavator and piled on the side slope.
[0013] Furthermore, during the formation of the trapezoidal rock wall, a safety platform with a width of not less than 5m is reserved or formed on the outside and is at the same level or one level lower than the bottom of the opening ditch, and pumice and rocks are accumulated on the safety platform near the side slope.
[0014] The beneficial effects of the present invention are as follows: the mining method provided by the present application first opens an open-section ditch with a width of not less than 20m on a high and steep slope along the length direction of the slope according to the expansion boundary in an open-pit mine, and forms a trapezoidal rock wall on the side facing the slope, and then performs lateral blasting and expansion and shoveling mining operations on the ore rock on the non-slope side in the open-section ditch, and after the mining and recovery of the inner ore is completed, the trapezoidal rock wall on the side facing the slope is mined, and after the trapezoidal rock wall is mined, the pumice and rock on the slope surface are cleaned to form a working platform with a width of not less than 40m; then, based on the working platform, the ore rock on the inner side of the working platform is continuously subjected to lateral blasting and expansion and shoveling mining operations, and the aforementioned steps are repeated on the side of the working platform facing the slope to form a working platform with a width of not less than 40m in the next section, and so on until the mining of all the open-pit mine expansion and recovery hanging ore bodies that need to be mined is completed. In this way, since the mining method of the present application first digs a section trench on the high and steep slope of the open-pit mine and forms a trapezoidal rock wall on the side facing the slope before large-scale mining, and then uses the trapezoidal rock wall to block the rolling stones generated during the section trench operation when mining on the side of the opening trench not facing the slope, and blocks and limits the rolling stones from falling to the deep concave open-pit mining operation area or the adjacent working platform through the trapezoidal rock wall, the purpose of preventing rolling stones from threatening the normal safe production of the lower part and not requiring the production to be stopped for the transition of the expansion wall is achieved, thereby achieving the purpose of simplifying the operation process, improving production efficiency, and ensuring safe production. The mining method of the present application is adopted. Due to the adjustment of the trenching method, the number of rolling stones in the expansion operation of the upper high and steep slope is effectively reduced. By creating slag cleaning conditions to restore the slag receiving capacity of the safety platform, the rolling stone hidden danger of the upper expansion wall to the lower production is eliminated, and the safety of the high and steep slope expansion and lower production of large deep concave open-pit mines under the coordinated operation is improved, ensuring the continuity and efficiency of safe and efficient production operations in the mine. The operation process is simple, the production efficiency is high, the safety is good, the scope of application is wide, and it is worthy of large-scale promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 It is a schematic diagram of the side expansion and segment trenching of the mining method for expanding and recovering the side ore body in an open-pit mine according to the present invention;
[0016] Figure 2 It is a schematic diagram of the platform slag cleaning of the mining method for recovering the hanging ore body in an open-pit mine according to the present invention.
[0017] Markings in the figure are: opening ditch 1, trapezoidal rock wall 2, pumice and rock 3, working platform 4, top edge 5, excavator 6, support slope 7, and safety platform 8. DETAILED DESCRIPTION
[0018] like Figure 1 , Figure 2The present invention provides a mining method for recovering the hanging ore body in an open-pit mine, which can prevent rolling stones from threatening the normal safe production at the bottom and does not require stopping production for transitional expansion. The mining method described is to first open a trench 1 with a width of not less than 20m along the length direction of the slope on a high and steep slope according to the expansion boundary in an open-pit mine, and form a trapezoidal rock wall 2 on the side facing the slope, and then perform lateral blasting and expansion and shoveling mining operations on the ore rock on the non-slope side in the trench 1, and after the mining and recovery of the inner ore is completed, the trapezoidal rock wall 2 on the side facing the slope is mined, and after the trapezoidal rock wall 2 is mined, the pumice and rock 3 on the slope surface are cleaned to form a working platform 4 with a width of not less than 40m; then, based on the working platform 4, continue to perform lateral blasting and expansion and shoveling mining operations on the ore rock on the inner side of the working platform, and repeat the above steps on the side of the working platform facing the slope to form a working platform 4 with a width of not less than 40m in the next section, and so on until all the mining work of the open-pit mine expansion and recovery hanging ore bodies that need to be mined is completed. In this way, since the mining method of the present application first digs a section trench on the high and steep slope of the open-pit mine and forms a trapezoidal rock wall on the side facing the slope before large-scale mining, and then uses the trapezoidal rock wall to block the rolling stones generated during the section trench operation when mining on the side of the opening trench not facing the slope, and blocks and limits the rolling stones from falling to the deep concave open-pit mining operation area or the adjacent working platform through the trapezoidal rock wall, the purpose of preventing rolling stones from threatening the normal safe production of the lower part and not requiring the production to be stopped for the transition of the expansion wall is achieved, thereby achieving the purpose of simplifying the operation process, improving production efficiency, and ensuring safe production. The mining method of the present application is adopted. Due to the adjustment of the trenching method, the number of rolling stones in the expansion operation of the upper high and steep slope is effectively reduced. By creating slag cleaning conditions to restore the slag receiving capacity of the safety platform, the rolling stone hidden danger of the upper expansion wall to the lower production is eliminated, and the safety of the high and steep slope expansion and lower production of large deep concave open-pit mines under the coordinated operation is improved, ensuring the continuity and efficiency of safe and efficient production operations in the mine. The operation process is simple, the production efficiency is high, the safety is good, the scope of application is wide, and it is worthy of large-scale promotion and application.
[0019] Accordingly, combined with the actual situation of the production site, in order to block the rolling stones to the maximum extent and minimize the deflection of the slope, the width of the top edge 5 of each trapezoidal rock wall formed by the segmented ditch of the present application is not less than 5m. When the segmented ditch 1 is opened, the double-walled ditch is first dug out by an excavator, and then the segmented ditch with a width of not less than 20m and the outer trapezoidal rock wall 2 are formed in the process of blasting mining in the double-walled ditch. And the height of the ore rock mined by each working platform 4 does not exceed 7.5m per section, and the height of the ore rock formed by two adjacent working platforms 4 does not exceed 15m per layer. After digging the double-walled ditch, the slope angle of the side of the segmented ditch formed by the side blasting and side shoveling operation is ≤75°. The side blasting and side shoveling method is also used for the recovery of the trapezoidal rock wall 2. After the recovery of the trapezoidal rock wall 2, the floating stones and rocks 3 on the slope surface are cleaned by the excavator 6 and piled on the side slope 7. During the formation of the trapezoidal rock wall 2, a safety platform 8 with a width of not less than 5 m is reserved or formed on the outside and is at the same level as or one level lower than the bottom of the opening ditch. Pumice and rocks 3 are piled on the safety platform 8 near the side slope 7.
[0020] Furthermore, in order to facilitate the actual mining operation, the present application first designs the mining of the open-pit mine expansion recovery hanging ore body based on the exploration data before mining, forms a layer with a ore rock height not exceeding 15m according to the single step height, and then divides the layer into at least two sections with a single section height not exceeding 7.5m, and then marks the open-pit mine expansion recovery hanging ore body as the basis for excavation and / or blasting mining. At the same time, in order to improve production efficiency, along the length direction of the working platform 4, the mining area sequentially set on each working platform 4 can be one or more, and the distance between two adjacent mining areas is not less than 100m; the mining layer and / or mining section recovered and set into the open-pit mine rock body along the slope width direction can be one or more.
[0021] The technical solution of the present application is further described below through specific embodiments:
[0022] 1. Purpose of the invention of this application:
[0023] The purpose of the present invention is to propose a ditching and slag clearing method for high and steep slope expansion, namely the above-mentioned mining method, based on safe production under the coordinated operation of high and steep slope expansion and lower production in large deep open-pit mines. By adjusting the ditching method, the number of rolling stones in the upper high and steep slope expansion operation can be effectively reduced, slag clearing conditions can be created to restore the slag receiving capacity of the safety platform, eliminate the hidden danger of rolling stones caused by the upper expansion to the lower production, and ensure the continuity and efficiency of the safe and efficient production operations of the mine.
[0024] 2. Main technical solutions:
[0025] The technical problem solved by the present invention is to provide a trenching and slag clearing method for safe operation of high-steep slope expansion and lower production in a large deep-concave open-pit mine, wherein the high-steep slope expansion and lower normal production involve two spatial operation areas of the deep-concave open-pit mine, wherein the high-steep slope expansion is a secondary expansion of the boundary, the new level preparation is trenching on the fixed high-steep slope, and the lower normal production is normal mining and stripping operation according to the established deep-concave open-pit boundary, including the following steps:
[0026] 1) The high and steep slopes mentioned above are the high and steep slopes formed by the production of open-pit mines according to the established final boundary. The slope of the existing terrain is generally greater than 45°.
[0027] 2) The high and steep wall expansion described: Open-pit wall expansion is a planar outward expansion based on a predetermined final boundary, with the depth decreasing in layers according to a top-down mining method, and the layer height is the height of a single step.
[0028] 3) The above-mentioned trenching for expanding the wall: The expansion operation is also a type of hillside open-pit mining. It is necessary to dig a new horizontal trench, expand the trench into a working face, and then complete the mining operation. The conventional method of trenching in hillside open-pit mines is to form a minimum working space according to the height of a single step along the terrain. The blasting free surface of the initial stripping strip trenching operation is facing downward, which is prone to blasting and throwing rocks. Based on this, taking into account the shoveling efficiency of the equipment, the trenching operation of the initial stripping strip for expanding the wall adopts a single-step segmented double-arm trench. First, a trapezoidal rock wall is reserved on the outside of the trench, and the direction of the blasting free surface of the trench is changed. The trapezoidal rock wall is recovered again, and the blasting free surface is designed to be in the direction of the trench, thereby preventing the blasting and throwing rocks. This method is repeated once to complete the trenching preparation for a new horizontal step.
[0029] 4) The described expansion and slag removal: When the first segment trenching work is completed on a single step, a long-arm excavator is used to clean the slag on the slope and platform of the next segment to ensure that there is no floating stone on the outside of the blasting segment and that it is not disturbed by the blasting vibration and rolls down. At the same time, a safety platform against the side is cleared as a secondary slag receiving platform.
[0030] 5) The above method is carried out from top to bottom in sequence according to the wall expansion level, and repeated until all levels of wall expansion and platform slag removal operations are completed.
[0031] Embodiment 1
[0032] The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings and implementation methods. The protection scope of the present invention is not limited by the embodiments, and any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
[0033] The present invention proposes a trenching and slag removal method for high and steep slope expansion, involving two spatial operation areas, the upper high and steep slope steps are expanded and mined, and the lower part maintains normal mining operations. The specific implementation method includes the following steps:
[0034] Step 1: Divide the height of the single step of the side slope into sections and dig section trenches.
[0035] Step 2: The first excavation strip on the slope surface is opened by digging a double-wall trench.
[0036] Step 3: After the excavation of the section trench is completed, lateral blasting and expansion and shoveling operations are carried out on the non-air-facing side of the section trench, forming a trapezoidal rock wall on the air-facing side of the section trench to ensure working space and safety.
[0037] Step 4: After the above-mentioned area is recovered, lateral blasting and shoveling operations will be carried out on the trapezoidal rock wall.
[0038] Step 5: After completing the above-mentioned trench expansion and shoveling operations, use long-arm excavators and other excavation equipment to clean up the floating stones on the slope surface and the loose rocks trapped by the original safety platform.
[0039] Step 6: Carry out the above steps (wall expansion and trenching - ore rock mining - platform slag cleaning) from top to bottom according to the wall expansion boundary, and repeat the process until the wall expansion and platform slag cleaning operations of all platforms are completed.
[0040] The height of the segmented steps is 1 / 2 of the height of the single step of the side slope. In this embodiment, the height of the single step of the side slope is ≤15m, and the height of the segmented steps is ≤7.5m.
[0041] The minimum bottom width of the segment trench is determined according to the transportation mode, the type of excavation equipment, the rock properties, etc. In this embodiment, the minimum bottom width of the segment trench is 20m, and the trench slope angle is ≤75°.
[0042] The lateral blasting parameters are determined according to the properties of the ore and rock, geological conditions, blasting purpose and safety requirements.
[0043] The height of the trapezoidal rock wall is consistent with the height of the segmented steps, and the upper base width is not less than the designed safety platform width; in this embodiment, the height of the trapezoidal rock wall is ≤7.5m, and the upper base width is ≥5m.
[0044] The width 7 of the working platform between each layer is determined according to the requirements of equipment operation and personnel operation. In this embodiment, the width of the working platform between each section is ≥40m.
Claims
1. A mining method for recovering hanging ore bodies in open-pit mines, characterized by: The mining method comprises the following steps: firstly, in an open-pit mine, a trench (1) with a width of not less than 20 m is opened along the length direction of the high and steep slope according to the expansion boundary, and a trapezoidal rock wall (2) is formed on the side facing the slope; then, lateral blasting and expansion and shoveling mining operations are performed on the ore rock on the non-slope side in the trench (1); after the mining and recovery of the inner ore is completed, the trapezoidal rock wall (2) on the slope side is mined again; and after the mining of the trapezoidal rock wall (2) is completed, the pumice and rock (3) on the slope surface are cleaned to form a working platform (4) with a width of not less than 40 m; then, based on the working platform (4), lateral blasting and expansion and shoveling mining operations are continued on the ore rock on the inner side of the working platform, and the aforementioned steps are repeated on the side facing the slope of the working platform to form a working platform (4) with a width of not less than 40 m in the next section, and so on until the mining of all the open-pit mine external expansion and recovery hanging ore bodies that need to be mined is completed.
2. The mining method for recovering the hanging ore body in an open-pit mine according to claim 1 is characterized in that: The width of the top edge (5) of each trapezoidal rock wall formed by the trenching is not less than 5m.
3. The mining method for recovering the hanging ore body in an open-pit mine according to claim 1 or 2, characterized in that: When the trench section (1) is opened, a double-wall trench is first excavated by an excavator, and then blasting and mining are performed in the double-wall trench to form a trench section with a width of not less than 20m and an outer trapezoidal rock wall (2).
4. The mining method for recovering the hanging ore body in an open-pit mine according to claim 3 is characterized in that: The height of the ore rock mined by each working platform (4) does not exceed 7.5m per section, and the height of the ore rock formed by two adjacent working platforms (4) does not exceed 15m per layer.
5. The mining method for recovering the hanging ore body in an open-pit mine according to claim 4 is characterized in that: Before mining, the mining design of the open-pit mine expansion and recovery hanging wall ore body is carried out based on the exploration data. The ore rock layer with a height of no more than 15m is formed according to the single step height, and then the layer is divided into at least two sections with a single section height of no more than 7.5m. Then, markings are made on the open-pit mine expansion and recovery hanging wall ore body as the basis for excavation and / or blasting mining.
6. The mining method for recovering the hanging ore body in an open-pit mine according to claim 5 is characterized in that: Along the length direction of the working platform (4), the mining areas sequentially arranged on each working platform (4) may be one or more, and the distance between two adjacent mining areas is not less than 100m; the mining layers and / or mining sections extending into the open-pit mine rock mass along the width direction of the slope may be one or more.
7. The mining method for recovering the hanging ore body in an open-pit mine according to claim 3 is characterized in that: After digging the double-walled trench, the slope angle on one side of the open section trench formed by the side blasting and wall expansion shoveling operation is ≤75°.
8. The mining method for recovering the hanging ore body in an open-pit mine according to claim 7 is characterized in that: When the trapezoidal rock wall (2) is mined, lateral blasting and wall expansion and shoveling are also used.
9. The mining method for recovering the hanging ore body in an open-pit mine according to claim 1, characterized in that: After the trapezoidal rock wall (2) is mined, the pumice and rocks (3) on the slope surface are cleaned by an excavator (6) and piled on the side slope (7).
10. The mining method for expanding and recovering the hanging ore body in an open-pit mine according to claim 1, characterized in that: During the formation of the trapezoidal rock wall (2), a safety platform (8) with a width of not less than 5 m is reserved or formed on the outside and is at the same level as or one level lower than the bottom surface of the opening trench. Pumice and rocks (3) are accumulated on the safety platform (8) close to the side slope (7).