Integrated device for heavy metal pollution treatment of tailing sand

Abstract

The utility model discloses an integrated device for heavy metal pollution treatment of tailing sand, which comprises a sand washing tank unit and a water treatment unit, the sand washing tank unit consists of a plurality of groups of sand washing tanks, and each group of sand washing tank comprises a sand washing head, a sand lifting and washing pipe, a sand-water separator, an overflow weir, a baffle, an air inlet pipe, a water inlet pipe, an upper wastewater pipe, a lower wastewater pipe and a sand discharge port. The water treatment unit is positioned behind the sand washing tank unit and comprises a coagulation reaction tank, a flocculation reaction tank and a sedimentation tank. Through the device, the heavy metal content and the leaching concentration of the tailing sand can be reduced, the construction period of a tailing sand restoration treatment project is shortened, the restoration cost is reduced, and resource utilization of the tailing sand is promoted.

Description

Technical Field

[0001] The utility model relates to the technical field of ecological environment governance, and in particular to an integrated device for controlling heavy metal pollution in tailings sand. Background Art

[0002] With the development of economy, the scale of mining is increasing year by year. Tailings, ore dressing tailings, mine waste rock and other products produced by mining are exposed to the surface environment for a long time. The metal minerals in them are constantly releasing various toxic and harmful elements into water and soil under the action of surface runoff, precipitation infiltration, etc., which endangers the ecological environment. At present, safe barrier landfill is one of the main engineering measures for the treatment of tailings and tailings contaminated soil. After mixing the treatment agent (such as solidifying agent, stabilizing agent) with the tailings, it is transported to a rigid / flexible landfill for barrier landfill, which reduces the environmental risk of heavy metal pollutants in the tailings to a certain extent. However, most of the tailings in my country have a high total amount of heavy metals, a large treatment volume, a large landfill area and a high grade, resulting in high treatment project costs. The treatment progress and project implementation of tailings are slow, so that many tailings have not been timely reduced, harmless and resourced, which has increased the release time of heavy metals in tailings to the surrounding environment to a certain extent.

[0003] Small particles of soil and weathering layers adsorbed on tailings are one of the main sources of heavy metals released from tailings into the surrounding environment. Therefore, pre-treatment of tailings to reduce the content of small particles of soil and weathering layers can reduce the total amount of pollutants in tailings, which is of great significance for the subsequent comprehensive management and resource utilization of tailings. Summary of the invention

[0004] In view of the defects of the prior art, the utility model provides an integrated device for the treatment of heavy metal pollution in tailings sand. Through the device, the heavy metal content and leaching concentration of tailings sand can be reduced, the construction period of tailings sand repair and treatment projects can be shortened, the cost of treatment and repair can be reduced, and the resource utilization of tailings sand can be promoted.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] The utility model specifically relates to an integrated device for the treatment of heavy metal pollution in tailings sand, the device comprising a sand washing tank unit and a water treatment unit; the sand washing tank unit is composed of a plurality of groups of sand washing tanks, and a single group of sand washing tanks comprises a sand washing head, a sand lifting and washing pipe, a sand-water separator, an overflow weir, a baffle, an air inlet pipe, a water inlet pipe, an upper wastewater pipe, a lower wastewater pipe, and a sand discharge port; the lower part of the sand washing head is connected with the air inlet pipe and the water inlet pipe, compressed air is introduced into the air inlet pipe, high-pressure water is introduced into the water inlet pipe, and the water inlet pipe is fixed to the sand washing head to prevent falling off; the upper part of the sand washing head is connected with the lower part of the sand lifting and washing pipe; the upper part of the sand lifting and washing pipe is connected with the sand-water separator; the sand-water separator is connected with the overflow weir, and a baffle is arranged on the upper part of the sand-water separator; the overflow weir is connected with the upper wastewater pipe; the upper wastewater pipe is connected with the water treatment unit, the lower wastewater pipe is located at the side of the bottom of the sand washing tank, and the sand discharge port is located at the bottom of the sand washing tank. The water treatment unit comprises a coagulation reaction tank, a flocculation reaction tank and a sedimentation tank.

[0007] Furthermore, the sand lifting and washing pipe is divided into a tailings rushing section L1, a tailings friction section L2, and a tailings flushing section L3, and the length ratio L1:L2:L3=0.32:0.38:0.30.

[0008] Furthermore, the coagulation reaction tank, flocculation reaction tank and sedimentation tank are connected in sequence and are all equipped with a special stirring device.

[0009] Furthermore, the sedimentation tank is provided with PP filler, channel steel, mud outlet and mud collecting tank.

[0010] Furthermore, the sedimentation tank is equipped with a pH meter and a dedicated sedimentation filler, which is located in the middle of the sedimentation tank and below the water surface.

[0011] The utility model provides an integrated device for treating heavy metal pollution in tailings sand, which has the following beneficial effects:

[0012] (1) The water and air sand washing components can screen and wash the tailings sand, and at the same time, remove the heavy metals in the tailings sand, thereby reducing the heavy metal pollution load of the tailings sand.

[0013] (2) After the tailings sand is initially treated by this device, the total amount of pollutants and the leaching concentration are greatly reduced, which can reduce the subsequent disposal costs, shorten the subsequent treatment time, and speed up the efficiency of tailings sand treatment, which is more conducive to the resource utilization of tailings sand and has good economic benefits.

[0014] (3) By treating flushing wastewater and achieving wastewater recycling, the amount of pollution emissions in the region can be significantly reduced, promoting the synergy of pollution reduction and carbon reduction, and having good environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1It is a process roadmap for an integrated device to treat heavy metal pollution in tailings sand.

[0016] Figure 2 Schematic diagram of the internal structure of a single sand washing tank unit.

[0017] Figure 3 Schematic diagram of the sand washing head in the sand washing tank.

[0018] Figure 4 This is the plan layout of the integrated device for the treatment of heavy metal pollution in tailings sand.

[0019] Figure 5 This is a schematic diagram of the sedimentation tank cross section.

[0020] In the figure: sand washing head 1, sand lifting and washing pipe 2, sand-water separator 3, overflow weir 4, baffle 5, air inlet pipe 6, water inlet pipe 7, upper wastewater pipe 8, lower wastewater pipe 9, sand discharge port 10, 1# dosing tank 11, 2# dosing tank 12, 3# dosing tank 13, coagulation reaction tank 14, flocculation reaction tank 15, sedimentation tank 16, clean water outlet 17, PP filler 18, channel steel 19, mud discharge port 20, mud collecting tank 21. DETAILED DESCRIPTION

[0021] The technical solution of the utility model is further described in detail below in conjunction with the accompanying drawings:

[0022] like Figure 1 As shown, an integrated device for treating heavy metal pollution in tailings sand comprises a sand washing tank unit and a water treatment unit. The sand washing tank unit comprises a plurality of groups of sand washing tanks, and the water treatment unit comprises a coagulation reaction tank, a flocculation reaction tank and a sedimentation tank.

[0023] like Figure 2 , Figure 3As shown, the sand washing tank unit includes a sand washing head 1, a sand lifting and washing pipe 2, a sand-water separator 3, an overflow weir 4, a baffle 5, an air inlet pipe 6, a water inlet pipe 7, an upper wastewater pipe 8, a lower wastewater pipe 9, and a sand discharge port 10. The lower part of the sand washing head 1 is connected to the air inlet pipe 6 and the water inlet pipe 7. The air inlet pipe 6 is fed with compressed air, and the water inlet pipe 7 is fed with high-pressure water flow for cleaning tailings. The water inlet pipe is fixed to the sand washing head to prevent it from falling off; the upper part of the sand washing head 1 is connected to the lower part of the sand lifting and washing pipe 2; the sand lifting and washing pipe is used to lift and clean tailings. The sand lifting and washing pipe is divided into a tailings rushing section L1, a tailings friction section L2, and a tailings flushing section L3, with a length ratio of L1:L2:L3=0.32:0.38:0.30. The tailings rushing section L1 is used to accelerate the tailings in the pipe, and the tailings are discharged from the tailings. The sand friction section L2 is used for full friction cleaning of tailings in the pipe, and the tailings flushing section L3 is used for flushing tailings and promoting the separation of tailings adsorbents; the upper part of the sand lifting and washing pipe 2 is connected to the sand-water separator 3, and the sand-water separator 3 is used to separate the tailings after washing and the washing wastewater; the sand-water separator 3 is connected to the overflow weir 4, and a baffle 5 is arranged on the upper part of the sand-water separator 4 to prevent the tailings from flowing out; the overflow weir 4 is connected to the upper wastewater pipe 8, and the suspended matter and impurities enter the upper wastewater pipe with the washing wastewater through the overflow weir; the upper wastewater pipe 8 is connected to the water treatment unit. The lower wastewater pipe is located at the bottom side of the sand washing tank, and is used to empty the sand washing wastewater; the sand discharge port is located at the bottom of the sand washing tank to discharge the tailings after washing.

[0024] like Figure 4 , Figure 5 As shown, the cleaning wastewater and suspended solids enter the water treatment system, and then enter the coagulation reaction tank 14 and the flocculation reaction tank 15 in turn. The 1# dosing tank 11 and the 2# dosing tank 12 respectively add drugs and stir, and then enter the sedimentation tank 16 after being evenly mixed. The water quality pH is fed back online through the pH meter 22, and the pH is adjusted by adding drugs through the 3# dosing tank. After the precipitation reaction, the treated wastewater is discharged through the clean water outlet 17 or recycled. The sludge containing heavy metals is discharged through the sludge outlet 20 and classified and treated according to its pollution degree.

[0025] The 1# dosing tank 11, the 2# dosing tank 12 and the 3# dosing tank 13 are all provided with stirring devices.

[0026] The sedimentation tank 16 is provided with PP filler 18 , channel steel 19 , a mud discharge port 20 , and a mud collecting tank 21 .

[0027] The utility model is applied to a method for an integrated device for treating heavy metal pollution in tailings sand, comprising the following steps:

[0028] (1) Pour an appropriate amount of contaminated tailings sand from the top of the sand washing tank, inject cleaning water from the clean water inlet pipe 7, inject compressed air from the air inlet pipe 6, start the sand lifting and washing pipe 2 to fully clean the tailings sand, and the cleaning time is 10-30 minutes. The water injection flow rate of the clean water inlet pipe 7 is 0.5-5m3 / h, the air pressure injected into the air intake pipe 6 is 0.3-0.8MPa.

[0029] (2) After separation by the sand-water separator 3, the cleaning wastewater and suspended solids enter the water treatment system through the overflow weir 4 and the upper wastewater pipe 8, and the tailings after cleaning are discharged from the sand outlet 10. Sampling is performed to detect the total content of heavy metals and leaching concentration of the tailings after cleaning discharged from the sand outlet 10.

[0030] (3) After the cleaning wastewater and suspended solids enter the water treatment system, coagulants, flocculants, and acid-base regulators are added to the 1# dosing tank 11, 2# dosing tank 12, and 3# dosing tank 13, respectively, and stirred. Coagulants include but are not limited to aluminum chloride, aluminum sulfate, ferric sulfate, and ferric chloride. Flocculants include but are not limited to polyaluminum chloride (PAC), polyaluminum sulfate (PAS), polyaluminum phosphate (PAP), and polyferric sulfate (PFS). Acid-base regulators include but are not limited to NaOH, Na2CO3, HCl, and H2SO4. The stirring rate is 50-80r / min.

[0031] (4) After the flocculation reaction is completed, the wastewater enters the sedimentation tank 16. After sedimentation and separation by the PP filler 18, the treated wastewater flows out through the clean water outlet 17. The effluent is discharged or recycled. The sludge containing heavy metals is discharged through the sludge outlet 20 and classified according to its degree of pollution.

Claims

1. An integrated device for treating heavy metal pollution in tailings, characterized in that: The invention comprises a sand washing tank unit and a water treatment unit. The sand washing tank unit is composed of a plurality of sand washing tanks. A single sand washing tank comprises a sand washing head (1), a sand lifting and washing pipe (2), a sand-water separator (3), an overflow weir (4), a baffle (5), an air inlet pipe (6), a water inlet pipe (7), an upper wastewater pipe (8), a lower wastewater pipe (9), and a sand discharge port (10). The lower part of the sand washing head (1) is connected to the air inlet pipe (6) and the water inlet pipe (7). Compressed air is introduced into the air inlet pipe (6), and high-pressure water is introduced into the water inlet pipe (7). The water inlet pipe (7) is fixed to the sand washing head (1) to prevent it from falling off. The upper part of the sand washing head (1) is connected to the lower part of the sand lifting and washing pipe (2). The upper part of the sand lifting and washing pipe (2) is connected to the upper part of the sand lifting and washing pipe (2). The sand-water separator (3) is connected to the sand-water separator (3), the sand-water separator (3) is connected to the overflow weir (4), a baffle (5) is arranged on the upper part of the sand-water separator (3), the overflow weir (4) is connected to the upper wastewater pipe (8), the upper wastewater pipe (8) is connected to the water treatment unit, the lower wastewater pipe (9) is located at the side of the bottom of the sand washing tank, the sand discharge port (10) is located at the bottom of the sand washing tank, the water treatment unit is located behind the sand washing tank unit, and comprises a coagulation reaction tank (14), a flocculation reaction tank (15) and a sedimentation tank (16), which are connected in sequence and are all provided with a stirring device, and the sedimentation tank is provided with a PP filler (18), a channel steel (19), a mud discharge port (20), and a mud collecting tank (21) 1.

2. An integrated device for treating heavy metal pollution in tailings sand according to claim 1, characterized in that: The sand lifting and washing pipe (2) is divided into a tailings rushing section L1, a tailings friction section L2, and a tailings flushing section L3, and the length ratio L1:L2:L3=0.32:0.38:0.30 2.

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