A drainage network layout structure of an open-pit mine dump and a construction method thereof

Abstract

The application provides a strip mine dump drainage network layout structure and a construction method thereof, wherein an underground water collecting layer is arranged below the bottom of an underground water-bearing layer in the dump, and a surface water seepage collecting layer is arranged on the top of a dump step of a sub-top layer of the dump, so that the multiple influences of underground water and surface water on the dump are dealt with in layers and categories, and the negative influence of water bodies on the mechanical properties of dump materials is reduced from the root; the built-in drainage network can be constructed synchronously with the advancing process of the dump, and the water enrichment in the dumping process can be discharged in time without interrupting the normal production of the mine, so that the basic stability of the dump is effectively improved, meanwhile, the multiple parallel arranged collecting bag groups greatly expand the water collecting radiation range, reduce the layout cost of the drainage system, and cooperate with the water absorbing granular material in the collecting bag, the connected collecting pipeline and the negative pressure water collecting equipment, so that the water permeation migration and collection efficiency are strengthened through the negative pressure environment, and the water collecting and drainage effect of the dump is significantly improved.

Description

Technical Field

[0001] This invention relates to the field of open-pit safety production technology, and in particular to a drainage network layout structure and construction method for open-pit mine spoil heaps. Background Technology

[0002] The stability of spoil heaps in open-pit mines is crucial for mine production. In southern China, abundant groundwater and high rainfall lead to significant water accumulation in both shallow and deep sections of spoil heaps during and after their formation, greatly affecting the mechanical properties of the spoil materials and reducing the spoil heap's stability. Traditional open-pit mine drainage systems typically employ vertically installed drainage wells at the top of the spoil heap for pumping. While this method achieves good drainage, it has several drawbacks: first, drainage wells can only be constructed after the spoil heap reaches design standards, preventing timely drainage of accumulated water during the disposal process; second, drainage well installation is costly, and the drainage coverage is limited, requiring companies to weigh the cost against the effectiveness of drainage; and third, relying solely on the natural movement of water within fissures for collection results in limited water collection efficiency. Summary of the Invention

[0003] The purpose of this invention is to provide a drainage network layout structure and construction method for open-pit mine spoil heaps. By using materials above various water collection layers to generate continuous overburden pressure, internal moisture is forced to migrate. Under the dual influence of the negative pressure environment of the water collection network, the water collection effect is improved.

[0004] To achieve the above objectives, the present invention provides a drainage network layout structure for an open-pit mine spoil heap. A groundwater collection layer is located below the bottom of the aquifer within the spoil heap; a surface seepage collection layer is located at the top of the second-to-last spoil heap step; a drainage network is installed within both the groundwater collection layer and the surface seepage collection layer. The drainage network includes multiple rows of parallel water collection bag groups. Each row of water collection bag groups includes multiple sequentially connected water collection bags. The water collection bags are filled with absorbent granular material. Every two adjacent water collection bags in the same water collection bag group are interconnected by a water collection sleeve. A water collection pipe is buried below the water collection sleeve within the collection layer. The bottom end of the water collection sleeve is connected to the water collection pipe. Water collection wells are located on both sides of the bottom side of the open-pit mine. The two ends of the water collection pipe extend into the corresponding water collection wells. A negative pressure water collection device connected to the water collection pipe is installed in each water collection well.

[0005] Furthermore, the inner diameter of the two ends of the water collection bag gradually increases, and the water collection sleeve includes two symmetrical sub-sleeves. Both sub-sleeves are provided with connecting flanges at their ends. The ends of every two adjacent water collection bags in the same row of water collection bags pass through the corresponding sub-sleeves and then turn outward. After the ends of the water collection bags turn outward, they are clamped and sealed by the connecting flanges. The connecting flanges of the two sub-sleeves are fixed by bolts.

[0006] Furthermore, the inner diameter of the sub-sleeve is the same as the outer diameter of the middle part of the water collection bag.

[0007] Furthermore, the bottom end of the sub-sleeve is provided with a water outlet hole, which is connected to the water collection pipe through a three-way pipe, and a filter screen is installed at the connection between the water collection pipe and the water outlet hole.

[0008] Furthermore, the negative pressure water collection device is a vacuum pump, which is fixedly installed on the top of the water collection well.

[0009] Furthermore, the top of the groundwater catchment layer is level with the top of the underground aquifer.

[0010] Furthermore, when the bottom boundary of the underground aquifer is level with or lower than the bottom of the open-pit mine, the groundwater catchment layer is constructed and arranged from the bottom of the open-pit mine.

[0011] Furthermore, the surface infiltration water collection layer is provided in multiple layers along the height direction, and the distance between two adjacent surface infiltration water collection layers is not less than the height of one soil drainage step.

[0012] A construction method for a drainage network layout structure of an open-pit mine spoil heap, based on the drainage network layout structure of the open-pit mine spoil heap, includes the following steps: S1: During the disposal process of open-pit mine spoil heaps, when the conditions for the construction of groundwater aquifers are met, the relevant materials are disposed of to form a groundwater aquifer. When the thickness reaches about 2-3m, multiple water collection bag groups are arranged in parallel on its surface. The starting end of the water collection bag group is equipped with a sub-sleeve and connected to the water collection pipe at the corresponding position. The water collection pipe extends to the water collection well and is connected to the negative pressure water collection equipment. S2: Once all the above equipment is completed and can generate a negative pressure environment, continue to discharge materials normally above the groundwater aquifer, which will continuously increase the overlying pressure on the groundwater aquifer, forcing the internal water to migrate. At the same time, under the dual influence of the negative pressure environment of the water collection network, the water in the groundwater aquifer will seep into the water collection bag, then migrate to the nearest water collection pipe, and then be collected in the water collection well. Finally, the water in the water collection well will be pumped out to the surface by the water pump.

[0013] Furthermore, the groundwater catchment layer and the level below it in the spoil heap extend along the mining advance direction, continuously extending the layout of the water collection bag group. When the extension of the groundwater catchment layer reaches 1 / 2 or 1 / 3 of the annual advance length of the spoil heap, the extension is paused, and a single sub-sleeve is installed at the end of the water collection bag and connected to the corresponding water collection pipe. The water collection pipe extends to the corresponding water collection well, and the level of the spoil heap above the groundwater catchment layer follows the advance. Under the dual action of overlying pressure and negative pressure, water collection is achieved.

[0014] The technical solution of this invention addresses the multiple impacts of groundwater and surface water on the spoil heap by arranging a groundwater collection layer below the bottom of the aquifer within the spoil heap and a surface water collection layer at the top of the second-to-last spoil heap step. This allows for layered and categorized management of the spoil heap, adapting to the drainage conditions of open-pit mines in southern regions with high rainfall and abundant groundwater. It fundamentally reduces the negative impact of water on the mechanical properties of spoil heap materials. The built-in drainage network can be constructed synchronously with the spoil heap construction process, enabling timely drainage of accumulated water during spoil heap construction without interrupting normal mine production. This effectively improves the foundation stability of the spoil heap. Simultaneously, the multiple rows of parallel water collection bags significantly expand the water collection range and reduce the deployment cost of the drainage system. Combined with the absorbent granular material inside the water collection bags, the connected water collection pipelines, and the negative pressure water collection equipment, the negative pressure environment enhances the efficiency of water infiltration, migration, and collection, significantly improving the water collection and drainage effect of the spoil heap. Attached Figure Description

[0015] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is a diagram showing the height of the drainage network according to the present invention.

[0017] Figure 2 This is a top view showing the layout of the drainage network of the present invention.

[0018] Figure 3 This is a diagram showing the connection between the water collection belt and the water collection sleeve.

[0019] Figure 4 This is a schematic diagram of the connection structure between two adjacent water collection bags in the same row of water collection bags.

[0020] Figure 5 This is a diagram showing the relationship between the water collection sleeve and the tee pipe.

[0021] Explanation of reference numerals in the attached diagram: 1-Groundwater catchment layer; 2-Surface seepage catchment layer; 3-Dumping area; 4-Groundwater aquifer; 5-Secondary top dumping step; 6-Water collection bag; 7-Dumping area advancement direction; 8-Water collection sleeve; 9-Bolt; 10-Water collection pipe; 11-Water outlet; 12-T-pipe; 13-Filter screen; 14-Water collection well; 15-Bottom side of open-pit mine; 16-Mining advancement direction. Detailed Implementation

[0022] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. 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.

[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] like Figures 1-5 As shown, the present invention provides a drainage network layout structure for an open-pit mine spoil heap. During the formation of the spoil heap 3, a groundwater collection layer 1 is arranged in the spoil heap 3 at a position 1-2m below the bottom of the underground aquifer 4. The groundwater collection layer 1 is formed by dumping large-fissure materials from the open-pit mine. The top of the groundwater collection layer 1 is level with the top of the underground aquifer 4.

[0026] If the bottom boundary of the underground aquifer 4 is level with or lower than the bottom level of the open-pit mine (representing the absolute height of a certain location relative to sea level), the groundwater catchment layer 1 shall be constructed starting from the bottom level of the pit.

[0027] When the underground aquifer 4 has multiple layers, the groundwater collection layer 1 is arranged one by one. However, when the distance between adjacent underground aquifer 4 is less than the height of one spoil step, only one groundwater collection layer 1 is arranged in the lower underground aquifer 4.

[0028] The top of the third or fourth top spoil heap can also form a surface infiltration water collection layer 2 by discharging materials from large gaps in the open-pit mine; the thickness of the surface infiltration water collection layer 2 is 1 / 3 to 1 / 4 of the height of the corresponding spoil heap. In areas with high rainfall, 1-2 additional surface infiltration water collection layers 2 can be added according to the specific amount of rainfall and water infiltration, and the distance between two adjacent surface infiltration water collection layers 2 should not be less than the height of one spoil heap.

[0029] Both the groundwater catchment layer 1 and the surface seepage catchment layer are equipped with drainage networks. These networks consist of multiple rows of parallel water collection bag groups. Each row comprises several sequentially connected water collection bags 6. The water collection bags 6 are filled with fine sand or other absorbent granular materials with similar properties and small gaps. The water collection bag groups are continuously positioned 2-3 meters above the bottom of each catchment layer, extending parallel to the direction of the spoil heap 7. The spacing between any two adjacent rows of water collection bag groups is approximately 10 meters. If there is a high moisture content within the spoil heap 3, the spacing between the water collection bag groups can be appropriately increased. Within the same water collection bag group, any two adjacent water collection bags 6 are connected by a... The water collection sleeves 8 are interconnected. The water collection bag 6 is a cylindrical structure made of nylon, open at both ends, with an inner diameter of 20-30cm in the middle. The inner diameter of the water collection bag 6 gradually increases to 50-60cm at both ends. The water collection sleeve 8 includes two symmetrical sub-sleeves. The inner diameter of the sub-sleeves is the same as the outer diameter of the middle part of the water collection bag 6. Both sub-sleeves are equipped with connecting flanges at their ends. The ends of every two adjacent water collection bags 6 in the same row of water collection bags pass through the corresponding sub-sleeves and then turn outward. After the ends of the water collection bags 6 turn outward, they are clamped and sealed by the connecting flanges. The connecting flanges of the two sub-sleeves are fixed by bolts 9 to realize the connection between two adjacent water collection bags 6 in the same water collection bag group.

[0030] After the water collection bag assembly is laid out to a certain length, a water collection pipe 10 is installed at the end of the assembly. The water collection bag 6 at the end passes through the sub-sleeve and then folds outward. A sealing cover is installed on the outer end of the sub-sleeve using bolts 9, sealing the water collection bag 6 and the sub-sleeve together. When the sub-sleeve is used to connect two adjacent water collection bags 6, the outlet hole 11 is sealed with bolts 9. The bottom end of the sub-sleeve has an outlet hole 11. When the sub-sleeve is used to connect the water collection pipe 10, a three-way pipe 12 and a filter screen 13 are installed at the outlet hole 11. Each three-way pipe 12 is connected to the water collection pipe 10 and finally connected to the corresponding water collection well 14. Water collection wells 14 are provided on both sides of the bottom wall 15 of the open-pit mine. The two ends of the water collection pipe 10 extend into the corresponding water collection well 14, and a negative pressure water collection device connected to the water collection pipe 10 is installed in the water collection well 14.

[0031] The negative pressure water collection device is a suction fan, which is fixedly installed on the top of the water collection well 14. Its purpose is to create a negative pressure state for the entire water collection network, including the water collection well 14, the water collection pipe 10, and the water collection bag 6, thereby enhancing the collection and infiltration migration rate of internal water. A water pump is installed inside the water collection well 14 to pump the water from the well to the ground surface.

[0032] When the bottom boundary of the underground aquifer 4 is level with or lower than the bottom of the open-pit mine, the groundwater collection layer 1 is constructed and arranged from the bottom of the open-pit mine.

[0033] The technical solution of the present invention also provides a construction method for the drainage network layout structure of the open-pit mine spoil heap 3, which is based on the drainage network layout structure of the open-pit mine spoil heap 3, and includes the following steps: S1: During the dumping process of open-pit mine spoil heap 3, when the conditions for constructing groundwater aquifer 1 are met, the relevant materials are dumped to form groundwater aquifer 1. When the thickness reaches about 2-3m, multiple water collection bag groups are arranged in parallel on its surface. The starting end of the water collection bag group is equipped with a sub-sleeve and connected to the corresponding water collection pipe 10. The water collection pipe 10 extends to the corresponding water collection well 14 and is connected to the negative pressure water collection equipment. S2: Once all the above-mentioned equipment is completed and can generate a negative pressure environment, the construction of the groundwater aquifer 1 will continue above the water collection bag 6. This means that materials will continue to be discharged normally above the groundwater aquifer 1, creating a continuously increasing overburden pressure that forces internal moisture to migrate. Simultaneously, under the dual influence of the negative pressure environment of the water collection network, moisture in the groundwater aquifer 1 will seep into the water collection bag 6, migrate to the nearest collection pipe 10, and then collect in the collection well 14. Finally, a water pump will extract the water from the collection well 14 to the surface. In the two cases where no materials are discharged above the groundwater aquifer 1, there is no overburden pressure, or when the spoil heap 3 is completed and the overburden pressure becomes stable, the overburden pressure has little or no impact on the migration of moisture in the groundwater aquifer 1. In these cases, the negative pressure environment of the water collection network can still achieve the aforementioned water collection effect.

[0034] Concurrently with the aforementioned construction, the steps of spoil heap 3 at the level of groundwater catchment layer 1 and below extend along the mining advance direction 16. Following the method described above, the water collection bag group is continuously extended along the spoil heap advance direction 7, and the Nth water collection pipe 10 and the Nth water collection well 14 are constructed sequentially to achieve water collection and drainage throughout the entire spoil heap 3. The layout of the water collection bag group is continuously extended. When the extension of groundwater catchment layer 1 reaches 1 / 2 or 1 / 3 of the annual advance length of spoil heap 3, the extension is paused, and a single sub-sleeve is installed at the end of the water collection bag 6 and connected to the water collection pipe 10 buried at the corresponding position. The water collection pipe 10 extends to the corresponding water collection well 14. The steps of spoil heap 3 above groundwater catchment layer 1 follow the advancement, and water collection is achieved under the dual action of overburden pressure and negative pressure.

[0035] Following the aforementioned method, the same water collection network is constructed within the surface infiltration water collection layer 2. To reduce construction costs, this part shares a set of water collection wells 14 with the water collection network of the groundwater collection layer 1.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A drainage network layout structure for an open-pit mine spoil heap, characterized in that, A groundwater collection layer is located below the bottom of the aquifer within the spoil heap; a surface seepage collection layer is located at the top of the second-to-top spoil heap step; both the groundwater collection layer and the surface seepage collection layer are equipped with drainage networks, which include multiple rows of parallel water collection bag groups. Each row of water collection bag groups includes multiple water collection bags connected in sequence. The water collection bags are filled with absorbent granular material. Every two adjacent water collection bags in the same water collection bag group are interconnected by a water collection sleeve. A water collection pipe is buried inside the collection layer below the water collection sleeve, and the bottom end of the water collection sleeve is connected to the water collection pipe. Water collection wells are provided on both sides of the bottom side of the open-pit mine. The two ends of the water collection pipe extend into the corresponding water collection wells, and negative pressure water collection equipment connected to the water collection pipe is installed in the water collection wells.

2. The drainage network layout structure of the open-pit mine spoil heap according to claim 1, characterized in that, The inner diameter of the water collection bag gradually increases at both ends. The water collection sleeve includes two symmetrical sub-sleeves. Both sub-sleeves are provided with connecting flanges at their ends. The ends of every two adjacent water collection bags in the same row of water collection bags pass through the corresponding sub-sleeves and then turn outward. After the ends of the water collection bags turn outward, they are clamped and sealed by the connecting flanges. The connecting flanges of the two sub-sleeves are fixed by bolts.

3. The drainage network layout structure of the open-pit mine spoil heap according to claim 2, characterized in that, The inner diameter of the sub-sleeve is the same as the outer diameter of the middle part of the water collection bag.

4. The drainage network layout structure of the open-pit mine spoil heap according to claim 2, characterized in that, The bottom end of the sub-sleeve is provided with a water outlet hole, which is connected to the water collection pipe through a three-way pipe. A filter screen is installed at the connection between the water collection pipe and the water outlet hole.

5. The drainage network layout structure of the open-pit mine spoil heap according to claim 1, characterized in that, The negative pressure water collection device is a vacuum pump, which is fixedly installed on the top of the water collection well.

6. The drainage network layout structure of the open-pit mine spoil heap according to claim 1, characterized in that, The top of the groundwater catchment layer is level with the top of the groundwater aquifer.

7. The drainage network layout structure for open-pit mine spoil heaps according to claim 1, characterized in that, When the bottom boundary of the underground aquifer is level with or lower than the bottom of the open-pit mine, the groundwater catchment layer is constructed and arranged from the bottom of the open-pit mine.

8. The drainage network layout structure of the open-pit mine spoil heap according to claim 1, characterized in that, The surface infiltration water collection layer is provided in multiple layers along the height direction, and the distance between two adjacent surface infiltration water collection layers is not less than the height of one soil drainage step.

9. A construction method for a drainage network layout structure in an open-pit mine spoil heap, characterized in that, The implementation of the drainage network layout structure for open-pit mine spoil heaps according to any one of claims 1-8 includes the following steps: S1: During the disposal process of open-pit mine spoil heaps, when the conditions for the construction of groundwater aquifers are met, the relevant materials are disposed of to form a groundwater aquifer. When the thickness reaches about 2-3m, multiple water collection bag groups are arranged in parallel on its surface. The starting end of the water collection bag group is equipped with a sub-sleeve and connected to the water collection pipe at the corresponding position. The water collection pipe extends to the water collection well and is connected to the negative pressure water collection equipment. S2: Once all the above equipment is completed and can generate a negative pressure environment, continue to discharge materials normally above the groundwater aquifer, which will continuously increase the overlying pressure on the groundwater aquifer, forcing the internal water to migrate. At the same time, under the dual influence of the negative pressure environment of the water collection network, the water in the groundwater aquifer will seep into the water collection bag, then migrate to the nearest water collection pipe, and then be collected in the water collection well. Finally, the water in the water collection well will be pumped out to the surface by the water pump.

10. The construction method of the drainage network layout structure of the open-pit mine spoil heap according to claim 9, characterized in that, The groundwater catchment layer and the lower level of the waste dump extend along the mining advance direction, continuously extending the layout of the water collection bag group. When the extension of the groundwater catchment layer reaches 1 / 2 or 1 / 3 of the annual advance length of the waste dump, the extension is paused, and a single sub-sleeve is installed at the end of the water collection bag and connected to the corresponding water collection pipe. The water collection pipe extends to the corresponding water collection well. The waste dump steps above the groundwater catchment layer follow the advance, and water collection is achieved under the dual action of overburden pressure and negative pressure.

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