A multi-unit passive ecological treatment integrated device for acid mine wastewater

Abstract

The present invention discloses an integrated multi-unit passive ecological treatment device for acid mine wastewater. The first-stage regulating tank has several separating baffles / water-passing baffles embedded in the inner wall, dividing the first-stage regulating tank into at least one regulating tank space. A pH adjuster layer is provided at the left end of the separating baffles / water-passing baffles. The second-stage sedimentation tank has several separating baffles / water-passing baffles embedded in the inner wall, dividing the second-stage sedimentation tank into at least one sedimentation tank space. An alkaline slow-release material carrier is provided in the middle of each sedimentation tank space. The third-stage biochemical tank has several separating baffles / water-passing baffles embedded in the inner wall, dividing the third-stage biochemical tank into at least one biochemical tank space. Each biochemical tank space has a vertical flow artificial wetland body. The integrated multi-unit passive ecological treatment device for acid mine wastewater provided by the present invention can be used as a pilot test device for testing the passive ecological treatment of various abandoned mine acid wastewater components.

Description

Technical Field

[0001] The present invention relates to the technical field of mine wastewater treatment, and in particular to an integrated multi-unit passive ecological treatment device for acid mine wastewater. Background Art

[0002] Rapid industrial development has increased the demand for mineral resources. Tailings ponds and spoil dumps created during mining operations generate acid mine drainage (AMD), characterized by a low pH and high concentrations of metal ions and sulfates. This AMD can severely damage the surrounding environment and can remain active for decades or even centuries after mine closure, becoming a global environmental problem. The extent of AMD's environmental pollution depends on its pH and composition, which in turn varies depending on the geology of the mining area. For example, AMD produced at the Maurliden mine in Sweden has a relatively low acidity of 2.3, with zinc ion concentrations of 460 mg / L and iron ion concentrations of 400 mg / L. However, manganese and cadmium ion concentrations are relatively low, ranging from 0.3 to 49 mg / L. In contrast, the acid reservoir at a mine in Anhui Province has a pH of 2.9 ± 0.02, iron ion concentrations of 34.57 ± 4.00 mg / L, and manganese ion concentrations of 199.93 ± 19.48 mg / L.

[0003] Therefore, effective treatment technologies are needed to minimize the negative impact of AMD. In order to protect the environment and enhance ecological sustainability, proper prevention of the occurrence of AMD is one of the important prerequisites. However, once AMD is formed, choosing appropriate treatment and recovery measures becomes a top priority. Existing treatment technologies mainly focus on neutralizing, stabilizing and removing pollutants through physical, chemical and biological technologies. Among all the treatment options, very few are cheap and sustainable. Most are costly and may even cause secondary pollution. Therefore, the development of efficient and energy-saving treatment technologies is the current main trend.

[0004] Currently, there are two main categories of AMD treatment, namely active treatment and passive treatment. Active treatment technology involves applying chemicals to metals.

[0005] Ions can be removed by precipitation, adsorption, ion exchange and membrane technology, but active treatment requires external chemical reagents and consumes a lot of energy.

[0006] Since the early 1990s, passive treatment technologies have been gradually applied to AMD, mainly including biological treatment in constructed wetlands, chemical treatment of limestone drainage systems, and sulfate-reducing microbial reactors. Passive treatment technology for AMD is more suitable for the remediation of abandoned mines than active treatment because it has the advantages of low operating and maintenance costs. Passive treatment technology can be selected based on the ability to produce alkalinity and the efficiency of metal removal. For example, when the pH is less than 6, metals such as zinc and manganese are not easily removed. Therefore, passive treatment technology for limestone is not suitable. In order to effectively remove these metal ions, magnesium oxide or a combination of limestone and magnesium oxide is used as a passive treatment technology. Passive treatment is regarded as an alternative to active treatment because it does not require continuous chemical inputs, the sludge produced is smaller and more stable, and environmentally friendly materials are usually used. However, passive treatment usually requires a longer action time.

[0007] In summary, there's no universal technology for treating AMD. Because its composition and sources vary, the treatment technology and waste generated during treatment also vary. Therefore, developing a passive ecological treatment pilot plant for testing various AMD components to determine engineering parameters such as filler layer type, gradation, hydraulic retention time, and hydraulic loading is essential during the pre-design phase of AMD treatment. Summary of the Invention

[0008] In view of this, the present invention proposes an integrated multi-unit passive ecological treatment device for acid mine wastewater.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] An integrated multi-unit passive ecological treatment device for acid mine wastewater, wherein the integrated pool includes a first-stage regulating pool, a second-stage sedimentation pool, and a third-stage biochemical pool;

[0011] The inner wall of the first-stage regulating tank is provided with a plurality of dividing grooves, each of which is embedded with a separation partition / water-passing partition, dividing the first-stage regulating tank into at least one regulating tank space, and the left end of the leftmost separation partition / water-passing partition is provided with a pH regulator layer; the inner wall of the second-stage sedimentation tank is provided with a plurality of dividing grooves, each of which is embedded with a separation partition / water-passing partition, dividing the second-stage sedimentation tank into at least one sedimentation tank space; an alkaline slow-release material carrier is provided in the middle of each sedimentation tank space; the inner wall of the third-stage biochemical tank is provided with a plurality of dividing grooves, each of which is embedded with a separation partition / water-passing partition, dividing the third-stage biochemical tank into at least one biochemical tank space; each biochemical tank space is provided with a vertical flow artificial wetland tank body;

[0012] A water pipe is provided inside the first-stage regulating tank on the left side of the pH regulator layer, and a water pipe is provided inside all regulating tank spaces and the water pipe is provided in the lower end of all sedimentation tank spaces; a water pipe is provided in the upper end of all sedimentation tank spaces and the water pipe is provided in the lower end of all biochemical tank spaces, and a water pipe is provided in the upper end of all biochemical tank spaces; all water pipes are provided with valves and water pumps.

[0013] Preferably, the separation baffle is a solid baffle; and a water-passing groove is provided on the panel of the water-passing baffle.

[0014] Preferably, there are two pH adjusting agent layers; each of the pH adjusting agent layers is composed of an adjusting top plate connected to the front and rear side walls of the upper end of the first-stage adjusting tank, an adjusting bottom plate connected to the front and rear side walls of the lower end of the first-stage adjusting tank, a permeable plate, a filter plate, a filter plate and a permeable plate arranged longitudinally in sequence at a certain distance between the adjusting top plate and the adjusting bottom plate, and a filler layer filled in the chamber between the permeable plate and the filter plate; the filler layer is made of any one of limestone, magnesium oxide, and a combination of limestone and magnesium oxide.

[0015] Preferably, a tube hole is provided on the adjusting top plate at a position corresponding to the position between the two filter plates; a first flushing pipe is longitudinally passed through the tube hole; a portion of the first flushing pipe extending into the chamber between the two filter plates is provided with a plurality of flushing holes at certain intervals.

[0016] Preferably, the alkaline slow-release material carrier includes a precipitation front plate, a precipitation rear plate, a permeable reaction wall, a filter plate and an alkaline slow-release material carrier layer; the precipitation front plate and the precipitation rear plate are respectively connected to the front side plate and the rear side plate of the second-stage sedimentation tank, and the two permeable reaction walls are arranged between the precipitation front plate and the precipitation rear plate; two filter plates are longitudinally arranged at a certain distance between the two permeable reaction walls; and a plurality of adjacent alkaline slow-release material carrier layers are provided in the cavity between the filter plate and the inner wall of the second-stage sedimentation tank.

[0017] Preferably, the alkaline slow-release material carrier layer includes an activated carbon carrier and an alkaline slow-release material; each of the activated carbon carriers is provided with a plurality of accommodating through holes; the plurality of accommodating through holes are filled with an alkaline slow-release material; the alkaline slow-release material is calcium oxide.

[0018] Preferably, a tube hole is opened on the front plate and the rear plate corresponding to the position between the two filter plates; a second flushing pipe is horizontally passed through the tube hole; and a portion of the second flushing pipe extending into the chamber between the two filter plates is provided with a plurality of flushing holes at certain intervals.

[0019] Preferably, the inner bottom wall of each sedimentation tank space is provided with a stirring blade.

[0020] Preferably, the vertical flow artificial wetland pool body is composed of a ceramsite bottom layer, a uniformly mixed layer of rice straw organic matter and ceramsite, a ceramsite upper layer, an organic soil layer and a plant layer, which are arranged in sequence from bottom to top.

[0021] Preferably, the height of the ceramsite bottom layer is 0.2 m; the height of the uniformly mixed layer of rice straw organic matter and ceramsite is 1.2 m; the height of the ceramsite upper layer is 0.2 m; and the height of the organic soil layer is 0.2 m.

[0022] Compared with the existing technology, the beneficial effects of the present invention are:

[0023] (1) This multi-unit passive ecological treatment integrated device for acid mine drainage is a passive ecological treatment pilot test device that can be used to test the composition of various abandoned mine acid drainage. It can determine engineering technical parameters such as filler type, gradation, hydraulic retention time and hydraulic load, and meets the processes required in the pre-design stage of abandoned mine acid drainage treatment;

[0024] (2) The equipment structure ensures low strength requirements, and the internal cavity partitions of the equipment are designed in a targeted manner. The partitions can be flexibly adjusted according to the needs under different water quality composition combinations; the main function of the first-stage regulating tank is to adjust the pH, the second-stage sedimentation tank is mainly to intercept sediment and reduce the load of heavy metals such as iron and manganese entering the subsequent artificial wetland, and the main function of the third-stage biochemical tank is to further process heavy metals to achieve standard discharge and improve the surrounding environment;

[0025] (3) The multi-unit passive ecological treatment integrated device for acid mine wastewater has low operation and maintenance costs and is easy to operate. The integrated device is made of container-type high-strength carbon steel and can be reused. It has strong applicability and greatly reduces the cost of pilot tests. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall three-dimensional structure of the present invention;

[0027] Figure 2 It is a schematic diagram of the internal three-dimensional structure of the present invention;

[0028] Figure 3 It is an overall top view of the present invention;

[0029] Figure 4 for Figure 3 AA section view in the figure;

[0030] Figure 5 This is a front cross-sectional view of the valve, water pump and packing layer after the whole is installed in the present invention;

[0031] Figure 6 This is a schematic diagram of the three-dimensional structure after the first flushing pipe and the second flushing pipe are integrally installed in the present invention;

[0032] Figure 7 This is a top view of the first flushing pipe and the second flushing pipe after being integrally installed according to the present invention;

[0033] Figure 8 for Figure 7 BB section view in the figure;

[0034] Figure 9 for Figure 8 Enlarged view of part E in FIG;

[0035] Figure 10 for Figure 7 CC section view in the figure;

[0036] Figure 11 It is an overall front sectional view of the present invention;

[0037] Figure 12 Schematic diagram of the internal structure of the third-level biochemical pool of the present invention.

[0038] In the figure: 1. First-stage regulating tank; 101. Regulating tank space; 2. Second-stage sedimentation tank; 201. Sedimentation tank space; 3. Third-stage biochemical tank; 301. Biochemical tank space; 4. Dividing tank; 5. Separating baffle; 6. Adjusting top plate; 7. Adjusting bottom plate; 8. Permeable plate; 9. Filter plate; 10. Filling layer; 11. First flushing pipe; 12. Flushing hole; 13. Precipitation front plate; 14. Precipitation rear plate; 15. Permeable reaction wall; 16. Alkaline slow-release material carrier layer; 17. Accommodating through hole; 18. Second flushing pipe; 19. Stirring blade; 20. Water pipe; 21. Uniformly mixed layer of rice straw organic matter and ceramsite; 22. Ceramsite upper layer; 23. Organic soil layer; 24. Plant layer; 25. Valve; 26. Water pump; 27. Water baffle; 28. Water trough; 29. Ceramsite bottom layer. DETAILED DESCRIPTION

[0039] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0040] In the description of the present invention, unless otherwise specified, "plurality" means two or more; terms such as "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," and "tail" indicate positions or relationships based on those shown in the accompanying drawings. These terms are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limiting the present invention. Furthermore, terms such as "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "connected" and "connection" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integral connection; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediary. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0042] Example:

[0043] like Figure 1-12 As shown, a multi-unit passive ecological treatment integrated device for acid mine wastewater, the integrated pool includes a first-stage regulating pool 1, a second-stage sedimentation pool 2 and a third-stage biochemical pool 3.

[0044] A plurality of partition grooves 4 are provided on the inner wall of the first-stage regulating tank 1. A separation partition 5 / water-passing partition 27 is embedded in each partition groove 4, dividing the first-stage regulating tank 1 into at least one regulating tank space 101. Two pH adjusting agent layers are provided at the left end of the leftmost separation partition 5 / water-passing partition 27.

[0045] Each pH adjusting agent layer is composed of an adjusting top plate 6 connected to the front and rear side walls of the upper end of the first-stage adjusting tank 1, an adjusting bottom plate 7 connected to the front and rear side walls of the lower end of the first-stage adjusting tank 1, a permeable plate 8, a filter plate 9, a filter plate 9 and a permeable plate 8 arranged longitudinally in sequence at a certain interval between the adjusting top plate 6 and the adjusting bottom plate 7, and a filler layer 10 filled in the chamber between the permeable plate 8 and the filter plate 9; the filler layer 10 is made of any one of limestone, magnesium oxide, and a combination of limestone and magnesium oxide.

[0046] A pipe hole is opened on the adjusting top plate 6 at a position corresponding to the position between the two filter plates 9; a first flushing pipe 11 is longitudinally passed through the pipe hole; a portion of the first flushing pipe 11 extending into the chamber between the two filter plates 9 is penetrated by a plurality of flushing holes 12 at certain intervals.

[0047] A plurality of partition grooves 4 are provided on the inner wall of the second-stage sedimentation tank 2. Each partition groove 4 is embedded with a separation partition 5 / water partition 27 to divide the second-stage sedimentation tank 2 into at least one sedimentation tank space 201. An alkaline slow-release material carrier is provided in the middle of each sedimentation tank space 201.

[0048] The alkaline slow-release material carrier includes a front precipitation plate 13, a rear precipitation plate 14, a permeable reaction wall 15, a filter plate 9 and an alkaline slow-release material carrier layer 16; the front precipitation plate 13 and the rear precipitation plate 14 are respectively connected to the front side plate and the rear side plate of the second-stage sedimentation tank 2, and the two permeable reaction walls 15 are arranged between the front precipitation plate 13 and the rear precipitation plate 14; two filter plates 9 are longitudinally arranged at a certain distance between the two permeable reaction walls 15; a plurality of adjacent alkaline slow-release material carrier layers 16 are provided in the chamber between the filter plate 9 and the inner wall of the second-stage sedimentation tank 2.

[0049] The alkaline slow-release material carrier layer 16 includes an activated carbon carrier and an alkaline slow-release material. Each activated carbon carrier is provided with a plurality of accommodating through holes 17 . The plurality of accommodating through holes 17 are filled with an alkaline slow-release material. The alkaline slow-release material is calcium oxide.

[0050] The front and rear sedimentation plates 13 and 14 are provided with holes corresponding to the positions between the two filter plates 9. A second flushing pipe 18 is provided transversely through the holes. The portion of the second flushing pipe 18 that extends into the chamber between the two filter plates 9 is provided with a plurality of flushing holes 12 at regular intervals. A stirring blade 19 is provided on the inner bottom wall of each sedimentation tank space 201.

[0051] A groove is provided at the position of the adjusting base plate 7 corresponding to the first flushing pipe 11, so that the first flushing pipe 11 can be inserted into the groove of the adjusting base plate 7 to limit the position; a groove is provided at the position of the sedimentation rear plate 14 corresponding to the second flushing pipe 18, so that the second flushing pipe 18 can be inserted into the groove of the sedimentation rear plate 14 to limit the position.

[0052] A plurality of partition grooves 4 are provided on the inner wall of the third-level biochemical pool 3, each of which is embedded with a separation partition 5 / water partition 27, dividing the third-level biochemical pool 3 into at least one biochemical pool space 301; each biochemical pool space 301 is provided with a vertical flow artificial wetland pool body.

[0053] The vertical flow artificial wetland pond is composed of a ceramsite bottom layer 29, a uniformly mixed layer of rice straw organic matter and ceramsite 21, a ceramsite upper layer 22, an organic soil layer 23, and a plant layer 24, arranged in order from bottom to top. The height of the ceramsite bottom layer 29 is 0.2m; the height of the uniformly mixed layer of rice straw organic matter and ceramsite 21 is 1.2m; the height of the ceramsite upper layer 22 is 0.2m; and the height of the organic soil layer 23 is 0.2m.

[0054] A water pipe 20 is provided inside the first-stage regulating tank 1 on the left side of the pH regulator layer. A water pipe 20 is provided inside all regulating tank spaces 101 and the water pipe 20 is provided at the lower end of all sedimentation tank spaces 201. A water pipe 20 is provided at the upper end of all sedimentation tank spaces 201 and the water pipe 20 is provided at the lower end of all biochemical tank spaces 301. A water pipe 20 is provided at the upper end of all biochemical tank spaces 301. Valves 25 and water pumps 26 are provided on all water pipes 20.

[0055] The separation partition 5 is a solid partition; a water passage groove 28 is provided on the panel of the water passage partition 27.

[0056] The device can also be filled with other materials according to different experimental requirements and used multiple times. The preferred filler in this embodiment is to adapt to the needs of this experiment.

[0057] The working principle of the present invention is:

[0058] The present invention provides an integrated multi-unit passive ecological treatment device for acid mine drainage, which can be used to test the passive ecological treatment pilot test device of various abandoned acid mine drainage components to determine engineering technical parameters such as filler type, gradation, hydraulic retention time and hydraulic load;

[0059] like Figure 5 As shown, when the first-stage regulating tank 1, the second-stage sedimentation tank 2 and the third-stage biochemical tank 3 are all embedded with water-passing baffles 27, due to the presence of the water-passing slots 28 on the water-passing baffles 27, the first-stage regulating tank 1, the second-stage sedimentation tank 2 and the third-stage biochemical tank 3 actually have only one overall regulating tank space 101, one overall sedimentation tank space 201 and one overall biochemical tank space 301: at this time, the hydraulic retention time in the first-stage regulating tank 1, the second-stage sedimentation tank 2 and the third-stage biochemical tank 3 can be increased by By controlling the flow rate of the water pump 26 and the start time of the water pump 26, the adjustment is achieved. The hydraulic retention time is set to four levels of 30min, 45min, 60min, and 75min to detect the water quality. At this time, the packing layer 10 in the first-stage regulating tank 1 can be tested by using any one of limestone, magnesium oxide, and a combination of limestone and magnesium oxide in batches. The packing layer 10 particle size is tested in four segmented layouts of 5-8mm, 8-10mm, 10-15mm, and 15-20mm.

[0060] like Figure 11As shown, when the first-stage regulating tank 1, the second-stage sedimentation tank 2 and the third-stage biochemical tank 3 are all embedded with separation partitions 5, since the separation partitions 5 are solid partitions, the first-stage regulating tank 1, the second-stage sedimentation tank 2 and the third-stage biochemical tank 3 are actually divided into multiple regulating tank spaces 101, multiple integral sedimentation tank spaces 201 and multiple integral biochemical tank spaces 301: at this time, the hydraulic retention time in the multiple regulating tank spaces 101, the multiple integral sedimentation tank spaces 201 and the multiple integral biochemical tank spaces 301 can be adjusted by controlling the flow rate of the water pump 26 and the start time of the water pump 26. The hydraulic retention time is set to 30min, 45min, The water quality is tested at four levels: 60min and 75min; at this time, the filler layer 10 in each regulating tank space 101 can be tested with any one of limestone, magnesium oxide, and a combination of limestone and magnesium oxide in batches; the filler layer 10 particle size is tested in four segmented layouts of 5-8mm, 8-10mm, 10-15mm, and 15-20mm; and the hydraulic load setting changes in the first-stage regulating tank 1, the second-stage sedimentation tank 2, and the third-stage biochemical tank 3 can be adjusted by the number of blocks of the embedded movable partitions (to separate the number of regulating tank spaces 101, sedimentation tank spaces 201, and biochemical tank spaces 301) and the flow rate of the water pump 26.

[0061] Acid mine drainage (AMD) is pumped into the first-stage regulating tank 1 and drained into the first-stage regulating tank 1 through a water pipe 20. The pH value of the AMD reacts with the alkaline substances in the filler, and the pH is adjusted from about 3 to about 6.0.

[0062] After the water flows through the first-stage regulating tank 1 and adjusts the pH, it carries part of the sludge sediment and enters the lower end of the permeable reaction wall 15 of the second-stage sedimentation tank 2 through the water pipe 20. The water flows from small to upward, and the pollutants are intercepted by the alkaline slow-release material carrier layer 16. The alkaline slow-release material carrier layer 16 is composed of an activated carbon carrier and calcium oxide filled in the activated carbon carrier. The calcium oxide dissolves in water, making the OH in the water － Concentration increased, OH － Combined with various heavy metal ions to form precipitates, achieving the effect of removing various heavy metal ions. The removal effects of various heavy metal ions are shown in Table 1 below. The precipitates settle into the sludge hopper and are regularly self-absorbed and collected for centralized treatment.

[0063] The supernatant from the second-stage sedimentation tank 2 enters the lower end of the vertical flow artificial wetland tank containing the organic layer through the water pipe 20, and the water pipe extending into the lower end of the permeable reaction wall 15 of the second-stage sedimentation tank 2 is provided with multiple water distribution holes to serve as water distribution pipes, and the water pipe extending into the lower end of the vertical flow artificial wetland tank is also provided with multiple water distribution holes to serve as water distribution pipes; the hydraulic load of the artificial wetland is set to 1.5m 3 / (m2 *h)、2.0m 3 / (m 2 *h)、2.5m 3 / (m 2 *h)、3.0m 3 / (m 2 *h) Four levels of effluent quality are tested. The thickness of each layer of the vertical flow constructed wetland pool is as follows: a 0.2m ceramsite bottom layer 29 for wrapping the water inlet distribution pipe, a 1.2m layer 21 of evenly mixed rice straw organic matter and ceramsite to provide conditions for microbial growth and reproduction, a 0.2m ceramsite upper layer 22, and the top 0.2m organic soil layer for planting aquatic plants to improve the environment and provide nutrients for microorganisms. The water flows through the vertical flow constructed wetland pool to further undergo physicochemical and biological reactions, deeply removing heavy metal pollutants such as iron and manganese, so that the effluent meets discharge standards.

[0064] When it is necessary to flush the pH regulator layer and the alkaline slow-release material carrier, the first flushing pipe 11 and the second flushing pipe 18 are respectively inserted into the regulating top plate 6 and the precipitation front plate 13, and the first flushing pipe 11 and the second flushing pipe 18 are connected to the hose and clean water is passed into them, so that the clean water is flushed out from the flushing holes of the first flushing pipe 11 and the second flushing pipe 18 to flush the pH regulator layer and the alkaline slow-release material carrier to prevent the suspended matter and sediment adhered to the permeable plate 8, the filter plate 9 and the permeable reaction wall 15 from being flushed out. After flushing, the first flushing pipe 11 and the second flushing pipe 18 act as water suction pipes again, and under the action of the pump suction, the suspended matter and sediment flushed out from the pH regulator layer and the alkaline slow-release material carrier are adsorbed.

[0065] Based on the tested water quality components and previous test experience data, several test schemes (such as filler type, gradation, hydraulic retention time and hydraulic load and other engineering technical parameters) were set up for comparison to determine the parameters of the optimal combination, enriching the "one mine, one policy, one well, one method" management concept. For example, before the construction drawing design of the comprehensive mine water management project of the closed coal mine in Sanhe Town, Cili County, an on-site pilot test was carried out, and it was determined that the terminal water treatment process adopted was "anaerobic limestone ditch ALD + permeable biochemical reaction wall PRB + vertical flow constructed wetland VCW". The anaerobic limestone ditch filler was calcite with a gradation particle size of 8-20mm, a hydraulic retention time of 30min, and a hydraulic load of 10m 3 / (m 2* h), permeable biochemical reaction wall hydraulic load 3m 3 / (m 2* h), vertical flow artificial wetland hydraulic load 1.5~3m 3 / (m 2* h).

[0066] Table 1 Monitoring results of heavy metal ion concentrations

[0067] project PH Fe (mg / L) Mn (mg / L) Cu (mg / L) Zn (mg / L) Influent water quality 2.0～3.5 20.1～100.8 10.5～21.7 4.4～6.5 20.4～23.5 Outlet water quality 6.2～7.0 0.7～3.6 1.1～2.3 0.9～1.3 4.0～4.6 Average removal rate (%) / 96.5 89.5 79.8 80.4

[0068] The above are only preferred specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A multi-unit passive ecological treatment integrated device for acid mine drainage, characterized in that: The integrated pool includes a first-stage regulating pool (1), a second-stage sedimentation pool (2) and a third-stage biochemical pool (3); The inner wall of the first-stage regulating tank (1) is provided with a plurality of dividing grooves (4), each of which is embedded with a separation partition (5) / water-passing partition (27), dividing the first-stage regulating tank (1) into at least one regulating tank space (101), and a pH adjusting agent layer is provided at the left end of the leftmost separation partition (5) / water-passing partition (27); the inner wall of the second-stage sedimentation tank (2) is provided with a plurality of dividing grooves (4), each of which is embedded with a separation partition (5) / water-passing partition (27), the second-stage sedimentation tank (2) is divided into at least one sedimentation tank space (201); an alkaline slow-release material carrier is provided in the middle of each sedimentation tank space (201); a plurality of separation grooves (4) are provided on the inner side wall of the third-stage biochemical tank (3), and a separation partition (5) / water partition (27) is embedded in each separation groove (4), dividing the third-stage biochemical tank (3) into at least one biochemical tank space (301); a vertical flow artificial wetland tank body is provided inside each biochemical tank space (301); A water pipe (20) is provided inside the first-stage regulating tank (1) on the left side of the pH regulating agent layer, and a water pipe (20) is provided inside all regulating tank spaces (101), and the water pipe (20) is provided at the lower end of all sedimentation tank spaces (201); a water pipe (20) is provided at the upper end of all sedimentation tank spaces (201), and the water pipe (20) is provided at the lower end of all biochemical tank spaces (301); and a water pipe (20) is provided at the upper end of all biochemical tank spaces (301); all water pipes (20) are provided with valves (25) and water pumps (26); The separation partition (5) is a solid partition; a water passage groove (28) is provided on the panel of the water passage partition (27); The alkaline slow-release material carrier comprises a precipitation front plate (13), a precipitation rear plate (14), a permeable reaction wall (15), a filter plate (9) and an alkaline slow-release material carrier layer (16); the precipitation front plate (13) and the precipitation rear plate (14) are respectively connected to the front side plate and the rear side plate of the second-stage precipitation tank (2); the two permeable reaction walls (15) are arranged between the precipitation front plate (13) and the precipitation rear plate (14); two filter plates (9) are longitudinally arranged at a certain interval between the two permeable reaction walls (15); a plurality of adjacent alkaline slow-release material carrier layers (16) are arranged in a chamber between the filter plate (9) and the inner wall of the second-stage precipitation tank (2); The alkaline slow-release material carrier layer (16) includes an activated carbon carrier and an alkaline slow-release material; each of the activated carbon carriers is provided with a plurality of accommodating through holes (17); the plurality of accommodating through holes (17) are filled with an alkaline slow-release material; the alkaline slow-release material is calcium oxide.

2. The multi-unit passive ecological treatment integrated device for acid mine drainage according to claim 1, characterized in that: The pH adjusting agent layer has two layers; each pH adjusting agent layer is composed of an adjusting top plate (6) connected to the front and rear side walls of the upper end of the first-stage adjusting tank (1), an adjusting bottom plate (7) connected to the front and rear side walls of the lower end of the first-stage adjusting tank (1), a water-permeable plate (8), a filter plate (9), a filter plate (9) and a water-permeable plate (8) arranged longitudinally in sequence at a certain interval between the adjusting top plate (6) and the adjusting bottom plate (7), and a filler layer (10) filled in the chamber between the water-permeable plate (8) and the filter plate (9); the filler layer (10) is any one of limestone, magnesium oxide, and a combination of limestone and magnesium oxide.

3. The multi-unit passive ecological treatment integrated device for acid mine drainage according to claim 2, characterized in that: A pipe hole is provided on the adjusting top plate (6) at a position corresponding to the position between the two filter plates (9); a first flushing pipe (11) is longitudinally passed through the pipe hole; and a portion of the first flushing pipe (11) extending into the chamber between the two filter plates (9) is provided with a plurality of flushing holes (12) at regular intervals.

4. The multi-unit passive ecological treatment integrated device for acid mine drainage according to claim 1, characterized in that: The front precipitation plate (13) and the rear precipitation plate (14) are provided with tube holes at positions corresponding to the positions between the two filter plates (9); a second flushing pipe (18) is horizontally passed through the tube holes; and a portion of the second flushing pipe (18) extending into the chamber between the two filter plates (9) is provided with a plurality of flushing holes (12) at regular intervals.

5. The multi-unit passive ecological treatment integrated device for acid mine drainage according to claim 1, characterized in that: The inner bottom wall of each sedimentation tank space (201) is provided with a stirring blade (19).

6. The multi-unit passive ecological treatment integrated device for acid mine drainage according to claim 1, characterized in that: The vertical flow artificial wetland pool body is composed of a ceramsite bottom layer (29), a rice straw organic matter and ceramsite uniformly mixed layer (21), a ceramsite upper layer (22), an organic soil layer (23) and a plant layer (24) arranged in sequence from bottom to top.

7. The multi-unit passive ecological treatment integrated device for acid mine drainage according to claim 6, characterized in that: The height of the ceramsite bottom layer (29) is 0.2 m; the height of the rice straw organic matter and ceramsite uniformly mixed layer (21) is 1.2 m; the height of the ceramsite upper layer (22) is 0.2 m; and the height of the organic soil layer (23) is 0.2 m.

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