Open pit backfill drainage system and method

Abstract

The invention aims to provide a backfill drainage system and method for an open-air pit, aiming at solving the problems of the existing backfill drainage technology for the open-air pit. The backfilling drainage system for the open pit comprises a drainage pipe, a floating pump, a conveying pipeline, a backfilling body, a water filtering pipe, a vertical water well, a water suction pump, a water collecting pipe and a water guide pipe. Through the combined structure of the water filtering pipe and the vertical water well, internal seepage of the backfill body can be effectively discharged, and the drainage problem of internal seepage of backfill slurry of an open pit is solved. The drainage system has the advantages of simple structure, convenience in operation, high practicability and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of mine drainage, and in particular relates to an open pit backfill drainage system and method. Background Art

[0002] For open pits that are converted to underground mining, backfilling is required. Using cemented backfill slurry to treat open pits will produce a large amount of seepage. If the water in the pit cannot be discharged in time, it will inhibit the strength improvement of the backfill body. At the same time, there are seepage channels inside the backfill body. The seepage of backfill slurry into the underground mining area will seriously affect the normal progress of underground mining activities. In addition, open pits will also produce a large amount of water due to atmospheric precipitation.

[0003] Chinese patent CN 107268761 B discloses a partitioned step-stage energy dissipation relay drainage system and method for open-pit mines. This drainage method is based on making full use of the characteristics of large open-pit mines with high steps and wide platforms, changing the original design method of building intercepting ditches only on a single platform, and adopting a step-stage relay layout of multiple adjacent platforms, and at the same time, equipped with relevant supporting facilities such as a water collection pool, a step-stage relay drainage pipe and an energy dissipation clarification pool, changing the original single-layer single-zone water collection mode to a multi-layer multi-zone water collection mode. Chinese patent CN 219744196U discloses a drainage device at the bottom of an open-pit mine, including a mobile pump pool for collecting water and a clean water pump for drainage. The mobile pump pool is simple to construct and low in cost, and has the function of natural clarification of sewage. It can give play to the advantages of large flow and large head of the clean water pump, thereby achieving the purpose of efficient drainage at the bottom of the open-pit mine. However, the device does not propose an effective way to drain the backfill of the open pit. Chinese patent CN217781943 U provides a drainage structure for ecological restoration of open-pit mines. A positioning plate is placed on the drainage channel, an adjustment mechanism is arranged inside the positioning plate, a sleeve is arranged on the adjustment mechanism and is retracted by a first spring, and a baffle is arranged on the sleeve, and a blocking net is arranged on the baffle, which can intercept the surface debris of the water flow in the drainage channel to prevent the blockage of the drainage channel. However, the structure does not propose measures for internal drainage of mine ecological restoration. Since there is no effective method to solve the internal seepage of backfill slurry in open pits in the prior art, it is necessary to study this problem. Summary of the invention

[0004] The purpose of the present invention is to provide an open pit backfill drainage system and method to solve the problem that water seepage inside the slurry is difficult to discharge during the open pit backfill process in order to solve the problem that water seepage inside the slurry is difficult to discharge during the open pit backfill process.

[0005] One of the technical solutions of the present invention is an open pit backfill drainage system, comprising: a drainage pipe, a floating pump, a delivery pipeline, a backfill body, a filter pipe, a vertical well, a water pump, a water collection pipe, and a water guide pipe;

[0006] The filter pipe is located at the bottom of the backfill body of the open pit, and is arranged obliquely along the flow direction of the slurry. Several filter pipes are arranged in parallel on the same plane, and the lower ends of the filter pipes extend to the edge of the open pit and are connected to the water collecting pipe arranged at the edge of the open pit; a vertical water well is arranged on the surface of the open pit step, and the depth is the same as the height of the open pit step. A water pump is arranged at the bottom of the vertical water well, and the water pump is connected to the drainage pipe. The water collecting pipe is connected to the vertical water well through a water guide pipe; a conveying pipeline is arranged along the slope on one side of the open pit, which is used to convey the backfill slurry into the open pit to form a backfill body; a floating pump is arranged on the surface of the water body where water seeps from the surface of the backfill body and flows to the water collecting area formed away from one end of the conveying pipeline, and the floating pump is connected to the drainage pipe;

[0007] The middle and upper part of the water filter pipe wall is provided with a water permeable hole, and the water filter pipe can prevent fine particles from blocking the water permeable hole.

[0008] Furthermore, in the above-mentioned open pit backfill drainage system, the inclination angle between the filter pipe and the horizontal plane is 1 to 3 degrees.

[0009] Furthermore, in the above-mentioned open pit backfill drainage system, the water filter pipe has a water permeable hole diameter of 1.5-2.5 mm, a hole spacing of 3-6 mm, and the surface of the water filter pipe is wrapped with a geotextile or an anti-filter layer made of other materials to prevent fine particles from blocking the water permeable holes.

[0010] Furthermore, in the above-mentioned open pit backfill drainage system, the spacing between the filter pipes is 15 to 20 meters.

[0011] The second technical solution of the present invention is a method for backfilling and draining an open pit, comprising the following steps:

[0012] S1. Before the backfilling operation of the open pit, arrange the filter pipe, connect the water collecting pipe and the water guide pipe; complete the construction of the vertical well on the construction plane closest to the backfilling operation, arrange the drainage pipe connected to the floating pump, and arrange the water pump and the drainage pipe connected to the drainage pump at the bottom of the vertical well;

[0013] S2. Transport the backfill slurry to form a backfill body in the open pit. As the backfill body gradually solidifies, water seeps from the surface of the backfill body and flows to the end far away from the transport pipeline to form a water collection area. Place a floating pump in the water collection area to pump out the accumulated water and discharge it to the surface through a drainage pipe. The seepage inside the backfill body enters the water filter pipe. The seepage water flows along the water filter pipe to the water collection pipe and the water guide pipe, and enters the bottom of the vertical water well through the water guide pipe. The seepage water is pumped out by a water pump and discharged to the surface through the drainage pipe.

[0014] S3. When the height of the backfill slurry is less than 2 to 4 cm from the lower edge of the upper step of the open pit, the backfill process is terminated, that is, the backfill operation of one layer is completed; then the water pump in the vertical water well is taken out for next use, and the vertical water well of this layer is blocked to prevent a new layer of backfill slurry from flowing into the vertical water well;

[0015] S4. When a new layer of backfill is being carried out, steps S1-S3 are repeated.

[0016] The beneficial effects of the above technical solution of the present invention are as follows:

[0017] 1. The present invention can effectively discharge the internal seepage of the backfill body through the combined structure of the water filter pipe and the vertical water well, solving the drainage problem of the internal seepage of the backfill slurry in the open pit.

[0018] 2. The drainage system of the present invention has the advantages of simple structure, convenient operation and strong practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the drainage system of the present invention;

[0020] Figure 2 A schematic diagram of the water filter pipe structure of the drainage system of the present invention;

[0021] Figure 3 It is a schematic diagram of the drainage structure of the combined water filter pipe and vertical water well of the drainage system of the present invention;

[0022] Among them: 1-open pit; 2-drainage pipe; 3-floating pump; 4-water collection area; 5-transmission pipeline; 6-backfill body; 7-water filter pipe; 8-geotextile filter layer; 9-permeable hole; 10-vertical well; 11-water pump; 12-water collection pipe; 13-water guide pipe. DETAILED DESCRIPTION

[0023] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0024] Example 1

[0025] An open pit backfill drainage system, comprising: a drainage pipe 2, a floating pump 3, a delivery pipeline 5, a backfill body 6, a water filter pipe 7, a vertical water well 10, a water pump 11, a water collecting pipe 12, and a water guide pipe 13;

[0026] The filter pipe is located at the bottom of the open pit backfill body and is arranged obliquely along the slurry flow direction. The inclination angle of the filter pipe is 1 to 3 degrees. Several filter pipes are arranged in parallel on the same plane. The spacing of the filter pipes is 15 to 20 meters. The lower ends of the several filter pipes extend to the edge of the open pit and are connected to the water collecting pipe arranged at the edge of the open pit; the vertical water well is arranged on the surface of the open pit step, and the depth is the same as the height of the open pit step. A water pump is arranged at the bottom of the vertical water well, and the water pump is connected to the drainage pipe. The water collecting pipe is connected to the vertical water well through a water guide pipe; a conveying pipeline is arranged along the slope on one side of the open pit, which is used to convey the backfill slurry into the open pit to form a backfill body; a floating pump is arranged on the water body surface where water seeps from the surface of the backfill body and flows to the water collection area 4 formed away from one end of the conveying pipeline, and the floating pump is connected to the drainage pipe;

[0027] The middle and upper part of the water filter pipe wall is provided with water permeable holes, and the water permeable holes 9 of the water filter pipe are circular, with a hole diameter of 1.5-2.5mm and a hole spacing of 3-6mm. The surface of the water filter pipe is wrapped with a geotextile filter layer 8 to prevent fine particles from blocking the water permeable holes.

[0028] Example 2

[0029] A method for backfilling and draining an open pit, using the drainage system of Example 1, comprises the following steps:

[0030] S1. Before the backfilling operation of the open pit 1 is carried out, a water filter network is arranged, and the water collecting pipe and the water guide pipe are connected; the vertical water well is constructed on the construction plane closest to the backfilling operation, a drainage pipe connected to the floating pump is arranged, and a water pump and a drainage pipe connected to the drainage pump are arranged at the bottom of the vertical water well;

[0031] S2. Transport the backfill slurry to form a backfill body in the open pit. As the backfill body gradually solidifies, water seeps from the surface of the backfill body and flows to the end far away from the transport pipeline to form a water collection area. Place a floating pump in the water collection area to pump out the accumulated water and discharge it to the surface through a drainage pipe. Seepage inside the backfill body enters the water filter pipe. The seepage water flows along the water filter pipe to the water collection pipe and the water guide pipe, and enters the bottom of the vertical water well through the water guide pipe. The seepage water is pumped out by a water pump and discharged to the surface through the drainage pipe.

[0032] S3. When the height of the backfill slurry is less than 2 to 4 cm from the lower edge of the upper step of the open pit, the backfill process is terminated, that is, the backfill operation of one layer is completed; then the water pump in the vertical well is taken out for next use, and the vertical well of this layer is sealed with steel mesh and concrete to prevent a new layer of backfill slurry from flowing into the vertical well;

[0033] S4, when a new layer of backfilling is carried out, the steps of S1-S3 are repeated. As the open pit area is expanded with the backfilling, the length and number of the filter pipes 7 are also increased synchronously.

Claims

1. An open pit backfill drainage system, characterized in that: include: Drain pipes, floating pumps, delivery pipelines, backfill bodies, filter pipes, vertical wells, water pumps, water collection pipes, and water guide pipes; The filter pipe is located at the bottom of the backfill body of the open pit, and is arranged obliquely along the flow direction of the slurry. Several filter pipes are arranged in parallel on the same plane, and the lower ends of the filter pipes extend to the edge of the open pit and are connected to the water collecting pipe arranged at the edge of the open pit; a vertical water well is arranged on the surface of the open pit step, and the depth is the same as the height of the open pit step. A water pump is arranged at the bottom of the vertical water well, and the water pump is connected to the drainage pipe. The water collecting pipe is connected to the vertical water well through a water guide pipe; a conveying pipeline is arranged along the slope on one side of the open pit, which is used to convey the backfill slurry into the open pit to form a backfill body; a floating pump is arranged on the surface of the water body where water seeps from the surface of the backfill body and flows to the water collecting area formed away from one end of the conveying pipeline, and the floating pump is connected to the drainage pipe; The middle and upper part of the water filter pipe wall is provided with a water permeable hole, and the water filter pipe can prevent fine particles from blocking the water permeable hole.

2. The open pit backfill drainage system according to claim 1, characterized in that: The inclination angle between the water filter pipe and the horizontal plane is 1 to 3 degrees.

3. The open pit backfill drainage system according to claim 1, characterized in that: The water permeable holes of the water filter pipe have a diameter of 1.5 to 2.5 mm, a hole spacing of 3 to 6 mm, and a reverse filter layer for preventing fine particles from blocking the water permeable holes is wrapped on the surface of the water filter pipe.

4. The open pit backfill drainage system according to claim 1, characterized in that: The spacing between the water filter pipes is 15 to 20 meters.

5. The open pit backfill drainage system according to claim 3, characterized in that: The filter layer is geotextile.

6. A method for backfilling and draining an open pit, characterized in that: The steps include: S1. Before the backfilling operation of the open pit, arrange the filter pipe, connect the water collecting pipe and the water guide pipe; complete the construction of the vertical well on the construction plane closest to the backfilling operation, arrange the drainage pipe connected to the floating pump, and arrange the water pump and the drainage pipe connected to the drainage pump at the bottom of the vertical well; S2. Transport the backfill slurry to form a backfill body in the open pit. As the backfill body gradually solidifies, water seeps from the surface of the backfill body and flows to the end far away from the transport pipeline to form a water collection area. Place a floating pump in the water collection area to pump out the accumulated water and discharge it to the surface through a drainage pipe. The seepage inside the backfill body enters the water filter pipe. The seepage water flows along the water filter pipe to the water collection pipe and the water guide pipe, and enters the bottom of the vertical water well through the water guide pipe. The seepage water is pumped out by a water pump and discharged to the surface through the drainage pipe. S3. When the height of the backfill slurry is less than 2 to 4 cm from the lower edge of the upper step of the open pit, the backfill process is terminated, that is, the backfill operation of one layer is completed; then the water pump in the vertical water well is taken out for next use, and the vertical water well of this layer is blocked to prevent a new layer of backfill slurry from flowing into the vertical water well; S4. When a new layer of backfill is being carried out, steps S1-S3 are repeated.

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