A system for treating sour old mine water without power

Abstract

The application relates to the technical field of mine wastewater treatment, in particular to a system for treating acid old pit water without power, which comprises, in sequence from high to low according to the terrain slope, an adjusting pool, a first-stage falling exposure pool, a second-stage falling exposure pool, a third-stage falling exposure pool and a sedimentation pool. A water inlet pipe is arranged through the front end of the adjusting pool, a water outlet pipe is arranged through the rear end of the adjusting pool, the water inlet pipe is used for receiving acid old pit water, and the water outlet pipe is used for connecting the first-stage falling exposure pool. A drainage pipe is arranged at the tail end of the sedimentation pool, so that the problem that the existing acid old pit water treatment technology is strongly dependent on power and is not suitable for remote mining areas is solved.

Description

Technical Field

[0001] This application relates to the field of mine wastewater treatment technology, and in particular to a non-powered system for treating acidic old kiln water. Background Technology

[0002] Due to a lack of environmental awareness in the last century, many coal mines were illegally mined, leading to severe damage to underground mining areas. After the mines closed, groundwater or surface water seeped into the mining areas, forming acidic stagnant water (low pH, high content of sulfates, iron, and manganese). As the groundwater level rose, this acidic old mine water gushed to the surface, seriously polluting the surrounding water and soil environment.

[0003] The current mainstream treatment technology for acidic mine water mainly adopts a combination of mechanical and chemical treatment processes. Centrifugal pumps or multi-stage submersible pumps are used to lift and transport the water, and jet aerators or surface aerators are used for forced oxidation. Mechanical stirring devices are used to promote thorough mixing of reactants. In the chemical treatment stage, neutralizing agents such as lime milk and sodium hydroxide are used to adjust the pH value, and oxidants such as hydrogen peroxide and sodium hypochlorite are used to remove heavy metals.

[0004] The existing technical solutions mentioned above have the following drawbacks: the existing processing methods mainly rely on external energy and complex processes, have high power requirements, and are not suitable for use in remote mining areas. Utility Model Content

[0005] To address the problem that existing acidic old mine water treatment technologies are highly dependent on electricity and have poor applicability in remote mining areas, this application provides a non-powered system for treating acidic old mine water.

[0006] The above-mentioned technical objective of this application is achieved through the following technical solution:

[0007] A non-powered system for treating acidic old kiln water includes an equalization tank, a primary aeration tank, a secondary aeration tank, a tertiary aeration tank, and a sedimentation tank connected in sequence according to the slope of the terrain from high to low. The equalization tank has an inlet pipe at its front end and an outlet pipe at its rear end. The inlet pipe is used to receive acidic old kiln water, and the outlet pipe is used to connect to the primary aeration tank. The sedimentation tank has a drain pipe connected to its rear end.

[0008] By adopting the above scheme, acidic old kiln water enters the system through the inlet pipe. According to the terrain, under the action of gravity, it passes through the regulating tank, the primary aeration tank, the secondary aeration tank, the tertiary aeration tank and the sedimentation tank for filtration and sedimentation. Compared with the existing technology that requires external energy, this scheme solves the problem that the existing acidic old kiln water treatment technology is highly dependent on electricity and has poor applicability in remote mining areas.

[0009] Furthermore, the primary cascading aeration tank is filled with limestone with a particle size of 50-80mm; the secondary and tertiary cascading aeration tanks are both filled with manganese sand with a particle size of 6-10mm.

[0010] Furthermore, the primary, secondary, and tertiary cascading aeration tanks are connected by an effluent component a, with a single-stage drop height of 0.5-1.2m from the primary to the secondary to the tertiary cascading aeration tanks.

[0011] Furthermore, the effluent component a of the primary cascading aeration tank is located on the side wall near the secondary cascading aeration tank, and the effluent component a of the secondary cascading aeration tank is located on the side wall near the tertiary cascading aeration tank. Each effluent component a includes a vertical pipe and a horizontal pipe. The vertical pipe is placed vertically along the height direction of the tank body, and the horizontal pipe is perpendicularly connected to the vertical pipe and is used to connect to the next level tank body. The vertical pipe of each tank body is respectively buried in the packing material of the primary, secondary, or tertiary cascading aeration tank, and several water inlet holes are evenly opened on the periphery of the vertical pipe.

[0012] Furthermore, several effluent components a are provided in the primary, secondary, and tertiary precipitator a, and these components a are arranged horizontally and evenly along the side wall of the primary precipitator near the secondary precipitator or the side wall of the secondary precipitator near the tertiary precipitator.

[0013] Furthermore, the diameter of each of the water inlets is less than 6 mm.

[0014] Furthermore, a sludge collection trough is provided at the bottom of the sedimentation tank. The sludge collection trough is V-shaped with a slope of ≥5%. A sludge discharge pipe is connected to the side wall of the sludge collection trough near the tail end. The sludge discharge pipe is inclined.

[0015] By adopting the above solution,

[0016] In summary, this application has the following technical effects:

[0017] By setting up this system, acidic old kiln water enters the system through the inlet pipe. According to the terrain, under the action of gravity, it passes through the regulating tank, the primary aeration tank, the secondary aeration tank, the tertiary aeration tank and the sedimentation tank for filtration and sedimentation. Compared with the existing technology that requires external energy, this system solves the problem that the existing acidic old kiln water treatment technology is highly dependent on electricity and has poor applicability in remote mining areas.

[0018] A sedimentation tank was installed to collect sludge.

[0019] By setting an inlet hole and adjusting its diameter, the amount of material in the tank that enters the next tank through the inlet hole is reduced. Attached Figure Description

[0020] Figure 1This is a schematic diagram of a non-powered system for treating acidic old kiln water according to this application;

[0021] Figure 2 This is a schematic diagram of the structure of water outlet component a in this application.

[0022] In the diagram, 1 is the equalization tank; 11 is the inlet pipe; 12 is the outlet pipe; 2 is the primary aeration tank; 3 is the secondary aeration tank; 4 is the sedimentation tank; 41 is the drainage pipe; 42 is the sludge collection trough; 421 is the sludge discharge pipe; 5 is the outlet component a; 51 is the vertical pipe; 511 is the inlet hole; 52 is the horizontal pipe; 6 is the filter plate; and 7 is the tertiary aeration tank. Detailed Implementation

[0023] The present application will be further described in detail below with reference to the accompanying drawings.

[0024] Reference Figures 1-2 This embodiment provides a non-powered system for treating acidic old kiln water. In this embodiment, it is preferred to treat acidic old kiln water with a volume of 20 m3 / d, and the treatment system is constructed on an abandoned slope with a slope of ≥3%.

[0025] It includes an equalization tank 1, a primary cascading aeration tank 2, a secondary cascading aeration tank 3, a tertiary cascading aeration tank 7, and a sedimentation tank 4, which are connected in sequence according to the slope of the terrain from high to low. The components are interconnected and form a complete gravity-fed treatment chain based on the natural slope of the mine, which can achieve continuous treatment of acidic old kiln water without the need for external power input.

[0026] The equalization tank 1, as the first treatment unit of the system, is constructed with reinforced concrete and has dimensions of 5m×4m×2m with an effective volume of 30m³. The inlet pipe 11 is connected to the side wall at the front end of the equalization tank 1. The inlet pipe 11 is used to introduce acidic old kiln water. In this embodiment, the inlet pipe 11 is a DN50 PVC-U pipe.

[0027] A water outlet pipe 12 is installed on the side wall of the equalization tank 1 near the primary cascading aeration tank 2. The water outlet pipe 12 is connected to the primary cascading aeration tank 2 and is used to transport the water source in the equalization tank 1 to the primary cascading aeration tank 2. It should be noted that the height of the water outlet pipe 12 is located near the top wall of the primary cascading aeration tank, so that the water source can fully react with the packing material in the primary cascading aeration tank 2 under the action of gravity.

[0028] The equalization tank 1 is equipped with a filter plate 6. The filter plate 6 is placed vertically inside the equalization tank 1 and fixedly connected to the equalization tank 1. The filter plate 6 is located between the inlet pipe 11 and the outlet pipe 12. The filter plate 6 is used to intercept large particulate impurities that enter the equalization tank 1 through the inlet pipe 11, so as to prevent them from entering the first-stage drop aeration tank 2 and reduce the occurrence of subsequent blockage.

[0029] In other embodiments, the filter plate 6 may also be fixed to the side wall of the equalization tank 1 near the primary drop aeration tank 2, thereby increasing the storage space for impurities.

[0030] In this embodiment, the equalization tank 1 is used to receive and temporarily store the incoming water, balance instantaneous flow fluctuations, ensure stable incoming water for subsequent treatment units, mix incoming water from different time periods, reduce water quality fluctuations, create stable incoming water conditions for subsequent treatment, and remove some settleable suspended solids through gravity sedimentation to reduce the load on subsequent treatment.

[0031] The primary cascading aeration tank 2, the secondary cascading aeration tank 3, and the tertiary cascading aeration tank are connected by an effluent component a5. The single-stage drop height from the primary cascading aeration tank 2 to the secondary cascading aeration tank 3 to the tertiary cascading aeration tank 7 is 0.5-1.2m, preferably 0.8m in this embodiment. The effluent component a5 of the primary cascading aeration tank 2 is located near the side wall of the secondary cascading aeration tank 3, and the effluent component a5 of the secondary cascading aeration tank 3 is located near the side wall of the tertiary cascading aeration tank 7.

[0032] Each effluent assembly a5 includes a vertical pipe 51 and a horizontal pipe 52. The vertical pipe 51 is placed vertically along the height of the tank. The horizontal pipe 52 is perpendicularly connected to the vertical pipe 51 and is used to connect to the next stage tank. The vertical pipe 51 is buried in the packing material of the primary cascading aeration tank 2, the secondary cascading aeration tank 3, and the tertiary cascading aeration tank 7. Several water inlet holes 511 are evenly opened on the periphery of the vertical pipe 51, and the diameter of each water inlet hole 511 is less than 6mm. Similarly, the tertiary cascading aeration tank 7 and the sedimentation tank 4 are also connected by several effluent assemblies a5. Their arrangement and connection method are the same as those of the effluent assemblies a5 mentioned above, and will not be described in detail in this embodiment.

[0033] It should be noted that several effluent components a5 are provided in the primary cascading aeration tank 2, the secondary cascading aeration tank 3, and the tertiary cascading aeration tank 7. These effluent components a5 are arranged horizontally and evenly along the side wall of the primary cascading aeration tank 2 near the secondary cascading aeration tank 3 or the side wall of the secondary cascading aeration tank 3 near the tertiary cascading aeration tank 7, thereby increasing the water flow velocity. Similarly, the tertiary cascading aeration tank 7 and the sedimentation tank 4 are also connected by several effluent components a5. Their arrangement and connection are the same as those of the effluent components a5 mentioned above, and will not be elaborated upon in this embodiment.

[0034] A sludge collection trough 42 is provided at the bottom of the sedimentation tank 4. The sludge collection trough 42 is V-shaped with a slope of ≥5%. In this embodiment, the slope is preferably 8%. The side wall of the V-shaped sludge collection trough 42 near the tail end is connected to a sludge discharge pipe 421. The sludge discharge pipe 421 is inclined. The sludge collection trough 42 is used to collect the sediment in the sedimentation tank 4, and because the sludge discharge pipe 421 is inclined, the sediment can be discharged through the sludge discharge pipe 421.

[0035] The primary precipitator is filled with high-purity limestone packing material with a particle size of 50-80mm and a CaCO3 content of over 85%. Through the dissolution and neutralization effect of limestone, the primary precipitator can raise the pH of the influent from 2.5-4.0 to 5.5-6.0, while achieving approximately 50% iron ion precipitation and removal.

[0036] The secondary drop tank and the tertiary drop aeration tank 7 constitute the oxidation treatment section of the system. Both are filled with manganese sand with a particle size of 6-10mm (the particle size is larger than the aperture of the inlet hole 511, which can reduce the loss of manganese sand particles). The MnO2 content is not less than 35%. The secondary drop tank and the tertiary drop aeration tank 7 form a natural drop aeration effect through a drop of more than 0.5m (in this embodiment, the drop value is preferably 0.8m), which increases the dissolved oxygen concentration from 2mg / L of the inlet water to more than 6mg / L, providing a sufficient oxygen source for the catalytic oxidation of iron and manganese.

[0037] It should be noted that in this embodiment, the filter plates 6 in the equalization tank 1, the packing layers in the various stages of the cascading aeration tanks, and the V-shaped sludge collection trough 42 in the sedimentation tank 4 all require regular cleaning and maintenance. Based on the applicant's actual engineering application experience, under normal operating conditions (influent iron content ≤200mg / L, manganese content ≤30mg / L), it is recommended that the cleaning cycle be once every three months. Specifically, this includes: removing the screenings from the filter plates 6 in the equalization tank 1, flushing the sludge accumulated in the packing layer of the tank, and discharging sludge from the sedimentation tank 4. It should be noted that the actual cleaning cycle also needs to be flexibly adjusted based on the fluctuations in influent water quality (such as increased suspended solids due to rainy season scouring), the degree of packing consumption (limestone dissolution rate), and the amount of sludge accumulation, etc. This maintenance cycle is an empirical value derived from long-term operational data statistical analysis (such as packing blockage rate ≤15%, sludge accumulation ≤30% of tank volume, etc.), which falls within the scope of system operation and maintenance and is not part of the core innovation of this technical solution, so it will not be elaborated here.

[0038] It should be noted that this embodiment adopts a stepped series design. The equalization tank 1, with an effective volume of 30m³, provides 36 hours of hydraulic retention time. The first-stage aeration tank 2, the second-stage aeration tank 3, and the third-stage aeration tank 7, each with an effective volume of 20m³, extend the treatment cycle. Finally, a 25m³ sedimentation tank 4 is set up to achieve solid-liquid separation for nearly 30 hours. To prevent short-circuiting, the water inlet at the front end of the equalization tank 1 enters the first-stage aeration tank 2 through the end outlet pipe 12. The outlet components a5 are arranged in 2-3 per meter along the width of the tank. The vertical pipe 51 has <6mm inlet holes 511 (spaced 80mm) to ensure that the water flows evenly through the 1.5m thick limestone packing layer and the 1.5m thick manganese sand packing layer. The porosity of the packing layer of 35-40% provides sufficient reaction surface area while forming moderate water flow resistance. The above settings effectively avoid the phenomenon of water flowing in and out immediately, ensuring that each treatment unit obtains sufficient reaction time.

[0039] The specific implementation principle of the non-powered system for treating acidic old kiln water in this application embodiment is as follows: The acidic old kiln water first enters the equalization tank 1 through a water pipe, where water quality homogenization is completed within a volume of 30m³. During this process, approximately 40% of suspended solids naturally settle, and 15-20% of iron ions are oxidized to Fe³+. Then, the homogenized water enters the primary drop aeration tank 2 through the outlet pipe 12, where it undergoes a neutralization reaction with the limestone packing material, raising the pH from 2.5-4.0 to 5.5-6.0, while simultaneously removing 50% of the iron ions. The treated water then falls into the secondary aeration tank 3 with a drop of 0.8m. Under the catalysis of manganese sand packing, the dissolved oxygen rises to 4mg / L, removing most of the iron and manganese. After further treatment in the tertiary aeration tank 7, the dissolved oxygen exceeds 6mg / L, and the final effluent contains only low levels of iron and manganese with a stable pH of 6.5-7.5. Then, in the sedimentation tank 4, metal hydroxides are precipitated, separating the treated water from the sediment. The treated water is discharged through the drain pipe 41, and the sludge is discharged through the sludge discharge pipe 421.

[0040] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A non-powered system for treating acidic old kiln water, characterized in that: The system includes a regulating tank (1), a primary cascading aeration tank (2), a secondary cascading aeration tank (3), a tertiary cascading aeration tank (7), and a sedimentation tank (4) connected in sequence from high to low according to the terrain slope. The regulating tank (1) has an inlet pipe (11) at the front end and an outlet pipe (12) at the rear end. The inlet pipe (11) is used to receive acidic old cellar water, and the outlet pipe (12) is used to connect to the primary cascading aeration tank (2). The sedimentation tank (4) has a drain pipe (41) connected to its tail end.

2. The system for treating acidic old kiln water without power according to claim 1, characterized in that: The primary cascading aeration tank (2) is filled with limestone with a particle size of 50-80 mm; the secondary cascading aeration tank (3) and the tertiary cascading aeration tank (7) are both filled with manganese sand with a particle size of 6-10 mm.

3. The system for treating acidic old kiln water without power according to claim 1, characterized in that: The primary drop aeration tank (2), the secondary drop aeration tank (3) and the tertiary drop aeration tank (7) are connected by an effluent component a (5). The drop height of a single stage from the primary drop aeration tank (2) to the secondary drop aeration tank (3) to the tertiary drop aeration tank (7) is 0.5-1.2m.

4. The system for non-powered treatment of acidic old kiln water according to claim 3, characterized in that: The effluent component a (5) of the first-stage cascading aeration tank (2) is located on the side wall near the second-stage cascading aeration tank (3), and the effluent component a (5) of the second-stage cascading aeration tank (3) is located on the side wall near the third-stage cascading aeration tank (7). Each effluent component a (5) includes a vertical pipe (51) and a horizontal pipe (52). The vertical pipe (51) is placed vertically along the height direction of the tank body, and the horizontal pipe (52) is perpendicularly connected to the vertical pipe (51) and is used to connect to the next stage tank body. The vertical pipe (51) of each tank is buried in the packing of the primary cascading aeration tank (2), the secondary cascading aeration tank (3) or the tertiary cascading aeration tank (7), and several water inlet holes (511) are evenly opened on the periphery of the vertical pipe (51).

5. The system for non-powered treatment of acidic old kiln water according to claim 4, characterized in that: Several effluent components a (5) are provided in the primary cascading aeration tank (2), the secondary cascading aeration tank (3) and the tertiary cascading aeration tank (7). The several effluent components a (5) are arranged horizontally and evenly along the side wall of the primary cascading aeration tank (2) near the secondary cascading aeration tank (3) or the side wall of the secondary cascading aeration tank (3) near the tertiary cascading aeration tank (7).

6. The system for treating acidic old kiln water without power according to claim 4, characterized in that: The diameter of each of the aforementioned water inlet holes (511) is less than 6 mm.

7. The system for non-powered treatment of acidic old kiln water according to claim 1, characterized in that: The sedimentation tank (4) is provided with a sludge collection trough (42) at the bottom. The sludge collection trough (42) is V-shaped with a slope of ≥5%. The side wall of the sludge collection trough (42) near the tail end is connected to a sludge discharge pipe (421), which is inclined.

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