An acidic mine wastewater end passive hydraulic self-regulating treatment device and method

Abstract

The application discloses a kind of acidic mine wastewater end passive type hydraulic self-regulation processing equipment, including water distribution pool, alkali adjusting pool and sedimentation tank sequentially communicated along water flow direction, the alkali adjusting pool is filled with slow-release function material, the water outlet of the sedimentation tank is provided with flow regulating valve, the control mechanism is equipped in the sedimentation tank, the flow regulating valve includes valve body and valve core in the valve body, the control mechanism is connected with the valve core.The equipment of the application has low operation and maintenance cost and is easy to operate;It is passive operation, zero manual intervention without external power supply, without manual control of reagent addition or flow, perfectly adapts to the treatment scene of closed mine "remote, power shortage, difficult to reside operation and maintenance personnel", the operation and maintenance cost is reduced by more than 80% compared with traditional active treatment process, and is reduced by more than 50% compared with existing passive treatment process.

Description

Technical Field

[0001] This invention belongs to the field of mine water inflow treatment technology, and in particular to a passive hydraulic self-regulating treatment device and method for acidic mine wastewater at the end of the process. Background Technology

[0002] Currently, over half of my country's mines require restoration or repair due to ecological damage. The acidic water pollution problem from closed coal mines is severe, generating hundreds of millions of cubic meters of acidic mine wastewater annually. The main pollutants in this wastewater are pH, fluoride, and heavy metal ions such as iron, manganese, arsenic, lead, and antimony. The core difference between treating wastewater from closed and operating mines lies in the control logic, technical conditions, and treatment objectives determined by the "production status."

[0003] Mine water inflow refers to wastewater formed when groundwater and surface water flow into abandoned roadways or goaf areas through mining-induced fissures and water diversion channels after mine production ceases. Its core characteristics are mainly reflected in four aspects: water quality fluctuation, water volume uncertainty, pollution concealment, and limited treatment conditions. The water quality is complex and fluctuates dramatically: it is mainly acidic wastewater, with pH values ​​mostly between 2.87 and 7.92, and some mines are strongly acidic (pH≈3.5), containing high concentrations of iron, manganese, sulfates, and heavy metal ions. Iron content in some mines exceeds 5000 mg / L, making it highly corrosive. Water quality is significantly affected by the source of recharge: old mine workings water is strongly acidic and has high TDS characteristics due to pyrite oxidation; while water from karst aquifers tends to be neutral, leading to significant differences in water quality at different times from the same water inflow point.

[0004] Water volume is dynamic and difficult to predict: water inflow is significantly correlated with rainfall, exhibiting three fluctuation patterns: rapid rise and slow fall, slow rise and slow fall, and steady fluctuation. The ratio of wet to dry water volume can be more than 5 times. Rainfall replenishment has a lag (15 days to 1 month). The water storage capacity of the releasing body and the type of water conduit (karst conduit / fissure) determine the amplitude of water volume fluctuations. The annual water inflow of some mines can vary by several times or even tens of times.

[0005] The pollution sources are hidden and pose a high risk of spread: closed mine goaf areas and tunnels form underground labyrinths, with water inflow sources including atmospheric precipitation infiltration, release of water from carbonate rock aquifers, and retention of water from old workings, resulting in complex and concealed recharge pathways. In addition, the frequent conversion between groundwater and surface water in karst development areas makes it easy for pollution to spread rapidly to surrounding soils and rivers, forming a complex pollution situation of visible pollution and hidden infiltration.

[0006] The treatment scenarios are challenging: the water inrush points are mostly located in remote mountainous areas with inconvenient transportation and power shortages. Furthermore, the pollution points are numerous and widespread, making it difficult to construct large-scale treatment facilities in a centralized manner. Subsequent maintenance personnel and material supplies are also difficult to obtain. Summary of the Invention

[0007] Addressing the core characteristics of closed mine wastewater—complex fluctuations in water quality, unpredictable water volume dynamics, and remote treatment scenarios lacking adequate support—as well as the limitations of existing treatment technologies in handling water quality and volume fluctuations and high operation and maintenance costs in remote areas, this invention discloses a passive hydraulic self-regulating treatment process and equipment for acidic mine wastewater. Through a core hydraulic self-regulating design and passive treatment optimization and upgrades, it achieves a precise solution to the difficulties in treating closed mine wastewater.

[0008] To address the above problems, this invention discloses a passive hydraulic self-regulating treatment device for acidic mine wastewater, comprising a water distribution tank, an alkali adjustment tank, and a sedimentation tank connected sequentially along the water flow direction. The alkali adjustment tank is filled with a slow-release functional material. The outlet of the sedimentation tank is equipped with a flow regulating valve. The sedimentation tank is equipped with a control mechanism. The flow regulating valve includes a valve body and a valve core located within the valve body. The control mechanism is connected to the valve core.

[0009] As a further improvement to the above technical solution: The effective elevation adjustment range of the sedimentation tank is 0.5-2.0 meters, and the adaptive linear flow regulating valve is configured to support 2-20 meters within the elevation adjustment range. 3 / d Water volume fluctuation adjustment.

[0010] The slow-release material is either alkaline or oxidative, with a release rate of 50-70 mol / (t·d). After modification, the slow-release material allows for precise control of the release rate of alkaline substances (such as calcium ions and hydroxide ions) or oxidizing substances, ensuring that under different water quality conditions (pH 2.87-7.92, iron content 0-5000 mg / L), the pH value within the treatment system remains stable within the acceptable range of 6.5-8.5. Heavy metal ions are efficiently removed through neutralization precipitation and oxidation solidification reactions, avoiding fluctuations in treatment effectiveness due to sudden changes in water quality. The effective service life of the slow-release material can reach several years (specifically determined based on the inflow pollution load, ≥3 years under normal scenarios), far exceeding traditional passive treatment media (1-2 years). This significantly reduces the frequency and cost of material replacement in remote areas, addressing the pain point of "difficult media replenishment due to inconvenient transportation."

[0011] The water distribution tank is equipped with a flow guide plate and a pretreatment layer. The pretreatment layer uses crushed stone filter media with a particle size of 5-10mm.

[0012] The flow guide plate includes at least a first filter plate, a second filter plate, and a third filter plate. The mesh size of the first filter plate is smaller than that of the second filter plate, and the mesh size of the third filter plate is smaller than that of the second filter plate. The pretreatment layer is disposed between the first filter plate and the second filter plate.

[0013] The control mechanism includes a level gauge arranged in the sedimentation tank, the level gauge is connected to a controller, an actuator is provided on the valve core, the controller and the actuator are connected, and the controller controls the movement of the actuator to change the valve core opening.

[0014] The outlet is equipped with a hydroelectric generator, which is connected to the controller.

[0015] The alkali adjustment tank and sedimentation tank are equipped with water distributors. The alkali adjustment tank is configured to guide water flow from bottom to top to permeate through the slow-release functional material.

[0016] The sedimentation tank is equipped with an inclined tube sedimentation assembly, and the bottom of the sedimentation tank is provided with a sludge thickening zone.

[0017] The water distribution tank of this invention serves as a water buffer and uniform water distribution unit. After receiving incoming water, it disperses the water flow into a uniform flow through a guide plate, avoiding localized water flow impacts caused by water volume fluctuations. Simultaneously, a pretreatment layer is installed within the tank to initially remove large suspended particles in the water, reducing the risk of blockage in subsequent units. This design is suitable for the characteristics of closed mine water inflows, which are characterized by "high sand content and large fluctuations in suspended solids." The alkali adjustment tank is filled with alkaline slow-release or oxidative slow-release materials. The tank adopts a layered water distribution design, with water slowly permeating from bottom to top, fully contacting and reacting with the materials. The alkaline slow-release materials neutralize acidic wastewater and raise the pH value, while the oxidative slow-release materials oxidize ferrous and manganese ions into higher-valence oxides for precipitation. This dual action ensures effective water purification. The sedimentation tank employs an inclined tube sedimentation design, utilizing gravity to quickly separate the heavy metal precipitates generated in the reaction from the water, increasing sedimentation efficiency by more than 30% compared to traditional sedimentation tanks. A sludge concentration zone is set at the bottom of the tank, allowing the precipitates to settle and concentrate naturally, eliminating the need for frequent cleaning and further reducing maintenance workload.

[0018] This invention also discloses a passive hydraulic self-regulating treatment method for acidic mine wastewater at the end of the treatment process, comprising the following steps: S1: Pretreatment diversion: Acidic mine wastewater is introduced into the distribution tank. Through the diversion plate in the distribution tank, the wastewater flows through the first filter plate, the pretreatment layer and the second filter plate in sequence. The crushed stone filter media in the pretreatment layer intercepts large particulate impurities in the wastewater. After secondary filtration by the third filter plate, it is discharged out of the distribution tank. S2: Slow-release alkalinity adjustment: The wastewater pretreated in step S1 is evenly distributed through the water distributor in the alkalinity adjustment tank, guiding the water flow from bottom to top to penetrate through the slow-release functional material in the alkalinity adjustment tank. The alkaline or oxidizing substances released by the slow-release functional material react with the acidic components and pollutants in the wastewater to achieve the adjustment of wastewater pH and the oxidation removal of pollutants. S3: Sedimentation and separation: The wastewater after the alkali treatment in step S2 is introduced into the sedimentation tank through the water distributor. Under the action of the inclined tube sedimentation component, the reaction product flocs in the wastewater are rapidly settled to the sludge concentration zone at the bottom of the tank. S4: Passive hydraulic self-regulating drainage: When the liquid level in the sedimentation tank changes with the influent flow rate, the control mechanism transmits the liquid level signal to the valve core, driving the valve core to move and changing the flow cross-sectional area between the valve core and the valve body, achieving a flow rate of 2-20m. 3 The water volume fluctuation is adaptively adjusted, and the final treated wastewater is discharged through the outlet.

[0019] Compared with the prior art, the beneficial effects of the present invention are: This invention can specifically remove suspended solids, Fe, Zn, and other pollutants from acidic mine wastewater. It allows for flexible selection of slow-release materials (alkaline / oxidizing) based on water quality characteristics, achieving precise adaptation to a specific mine. Utilizing a level-valve self-feedback system, it achieves a 2-20m level control. 3 The adaptive adjustment of water flow fluctuations perfectly adapts to the unstable flow characteristics of mine wastewater. Combined with hydropower / solar power generation, it requires no external power source or manual intervention, achieving zero maintenance and making it suitable for remote, power-scarce closed mines. Maintenance costs are reduced by over 80% compared to traditional active processes and by over 50% compared to existing passive processes. Long-lasting slow-release materials and modular pool design reduce frequent maintenance and material replacement costs. The pool supports factory prefabrication / on-site construction, with an installation cycle of ≤15 days for rapid deployment. It can adapt to narrow, complex terrain in mountainous mines, solving the construction challenges of dispersed locations. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0021] Reference numerals in the attached drawings: 1. Water distribution tank; 10. Pretreatment layer; 11. Inclined tube sedimentation assembly; 12. Sludge thickening zone; 13. Valve body; 14. Water distributor; 2. Alkali adjustment tank; 3. Sedimentation tank; 4. Slow-release functional material; 5. Flow regulating valve; 6. Control mechanism; 9. Guide plate; 91. First filter plate; 92. Second filter plate; 93. Third filter plate. Detailed Implementation

[0022] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0023] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] like Figure 1 As shown in this embodiment, the core of the passive hydraulic self-regulating treatment equipment for acidic mine wastewater at the end of the treatment process lies in achieving passive and efficient treatment and hydraulic self-regulation of acidic mine wastewater. The equipment consists of a distribution tank 1, an alkalinity adjustment tank 2, and a sedimentation tank 3 connected in series along the water flow direction. Each tank is constructed using reinforced concrete (either factory prefabrication and on-site assembly or factory assembly and on-site hoisting). The tank wall thickness is designed to be 20-30cm based on site geological conditions to ensure structural stability. The distribution tank 1 is used for wastewater diversion and pretreatment; the alkalinity adjustment tank 2 adjusts the wastewater's pH and removes pollutants through oxidation; and the sedimentation tank 3 separates and settles reaction products. The hydraulic self-regulation function is achieved through a flow regulating valve 5 at the outlet of the sedimentation tank 3 and a control mechanism 6 within the tank. The tanks are connected by flanged pipes with an inner diameter of 100-200mm, matched to the designed treatment capacity. Sealing gaskets are installed at pipe connections to prevent wastewater leakage.

[0027] The effective volume of water distribution tank 1 is designed to be 5-8m³. 3This ensures that the wastewater has sufficient pretreatment retention time in the tank (designed retention time is 0.2-2 hours). A guide plate 9 and a pretreatment layer 10 are fixedly installed inside the tank. The guide plate 9 is made of 304 stainless steel or plastic and includes a first filter plate 91, a second filter plate 92, and a third filter plate 93 arranged in parallel. All three filter plates are fixed to the inner wall of the distribution tank 1 using expansion bolts (or by snap-fit ​​or by installing brackets in the distribution tank 1).

[0028] The mesh size of the first filter plate 91 is designed to be 1mm×1mm (or circular holes with a diameter of 1mm), the mesh size of the second filter plate 92 is designed to be 2mm×2mm (or circular holes with a diameter of 2mm), and the mesh size of the third filter plate 93 is designed to be 0.5mm×0.5mm (or circular holes with a diameter of 0.5mm). That is, the mesh sizes of the first filter plate 91 and the third filter plate 93 are smaller than the mesh size of the second filter plate 92. The pretreatment layer 10 is laid between the first filter plate 91 and the second filter plate (92), with a thickness of 30-50cm. It uses granite crushed stone filter media with a particle size of 5-10mm. The crushed stone filter media is laid after washing and screening to ensure that the filter media particles are uniform and the porosity reaches 40-50%. It can effectively intercept large particulate suspended solids (such as mine tailings particles, silt, etc.) in wastewater and avoid clogging of subsequent components. If the water distribution tank 1 adopts a sealed structure, an overflow port should be provided at the top of the first filter plate 91 (the bottom of the first filter plate 91 should not have mesh holes to reduce bottom blockage) so that water can quickly enter the next unit (at the second filter plate 91). A sludge discharge pipe should be installed at the bottom of the water distribution tank 1 to periodically remove the sediment in the water distribution tank 1.

[0029] The effective volume of alkali adjustment tank 2 is 10-15m³. 3 The residence time is designed to be 1-3 hours, and the tank is filled with slow-release functional material 4 to a height of 1.5-2.5m. In this embodiment, the slow-release functional material 4 is an alkaline slow-release material (such as slow-release limestone particles with a particle size of 20-50mm), and its slow-release rate is controlled at 50-70mol / (t·d), which can continuously release alkaline substances (Ca). 2 +、HCO3 - (etc.), to adjust the pH of acidic mine wastewater; if the wastewater contains Fe 2 +、Mn 2 For reducing pollutants such as +, slow-release oxidation materials (such as slow-release potassium permanganate carrier materials) can also be selected to oxidize the pollutants into easily precipitated high-valence compounds by releasing oxidizing substances.

[0030] A water distributor 14 is installed at the bottom of the alkali adjustment tank 2. The water distributor 14 uses a perforated pipe water distribution method. The perforation diameter of the perforated pipe is 5-8mm and the spacing between the perforations is 10-15cm. The water distributor 14 is connected to the upper part of the distribution tank 1 through a pipe (to extract water from the upper part of the third filter plate 93 so that the water in the distribution tank 1 can settle). The water distributor 14 can evenly distribute the pretreated wastewater to the bottom of the alkali adjustment tank 2, guide the water flow from bottom to top to penetrate through the slow-release functional material 4, so that the wastewater and the slow-release functional material 4 can fully contact and react, thereby improving the pH adjustment and pollutant removal effect.

[0031] The effective volume of sedimentation tank 3 is 8-12m³. 3 The sedimentation tank 3 is designed with a residence time of 1-3 hours and an effective elevation adjustment range of 0.5-2.0 meters to adapt to sedimentation requirements under different flow conditions. A water distributor 14 is also installed at the top of the sedimentation tank 3 to evenly introduce the alkali-treated wastewater into the sedimentation tank 3. An inclined tube sedimentation assembly 11 is installed inside the tank. The inclined tubes are made of polypropylene, with a regular hexagonal cross-section, an inscribed circle diameter of 50mm, an inclination angle of 60°, and an installation height of 1.0-1.5m. This significantly increases the sedimentation area and settling efficiency, allowing the reaction product flocs in the wastewater to settle rapidly. A sludge thickening zone 12 is located at the bottom of the sedimentation tank 3. The sludge thickening zone 12 has a conical structure with a cone angle of 60° to facilitate the accumulation of settled sludge. A sludge discharge pipe is installed at the bottom of the sludge thickening zone 12 for periodic discharge of concentrated sludge.

[0032] The outlet of sedimentation tank 3 is equipped with a flow regulating valve 5, which is configured to support a flow rate of 2-20m within an elevation adjustment range of 0.5-2.0 meters. 3 The system adjusts the water flow rate fluctuations to meet the treatment needs of acidic mine wastewater with unstable flow rates. A control mechanism 6 is installed within the sedimentation tank 3. The control mechanism 6 includes a level gauge (using an submersible level transmitter with a measurement accuracy of ±1mm) located within the sedimentation tank 3. The level gauge is connected to a PLC controller, model S7-200SMART. An actuator (using an electric actuator with an output torque of 5-10 N·m) is installed on the valve core of the flow regulating valve 5. The controller and actuator are connected by a cable.

[0033] To achieve passive hydraulic self-regulation, the level gauge monitors the liquid level in sedimentation tank 3 in real time and transmits the liquid level signal to the controller. The controller controls the actuator to move according to the preset liquid level threshold (corresponding to different flow requirements), thereby changing the valve core opening and adjusting the outflow of water from the outlet: when the inflow rate increases and the liquid level in sedimentation tank 3 rises above the preset upper limit, the controller controls the actuator to increase the valve core opening, increasing the outflow and preventing overflow due to excessive liquid level; when the inflow rate decreases and the liquid level in sedimentation tank 3 drops below the preset lower limit, the controller controls the actuator to decrease the valve core opening, reducing the outflow and ensuring sufficient sedimentation level and residence time in the tank.

[0034] Furthermore, a hydroelectric generator (a small axial-flow hydroelectric generator with a power of 500-1000W) is installed at the outlet. The generator is connected to the controller and generates electricity using the kinetic energy of the water flow at the outlet. This provides power to the level gauge, controller, and actuators, enabling passive operation of the equipment without the need for an external power source, thus reducing operating costs. Solar panels can also be installed to avoid situations where there is no power supply in mountainous areas.

[0035] Based on the aforementioned passive hydraulic self-regulating treatment equipment for acidic mine wastewater at the end of the treatment process, the treatment method in this embodiment specifically includes the following steps: S1: Pretreatment diversion: This involves diverting acidic mine wastewater (pH 2.0-4.0, containing suspended solids, Fe...) into the pretreatment system. 2 +、Mn 2 Pollutants (such as chlorine) are introduced into the distribution tank 1 through the inlet pipe. Under the guidance of the guide plate 9, the wastewater flows sequentially through the first filter plate 91, the pretreatment layer 10, and the second filter plate 92. The first filter plate 91 first performs preliminary filtration of the wastewater, intercepting some large particulate impurities. Then, the wastewater enters the pretreatment layer 10, where crushed stone filter media with a particle size of 5-10mm is used to further intercept large particulate suspended solids in the wastewater, reducing the load on subsequent treatment. The pretreated wastewater is then filtered a second time through the second filter plate 92 and the third filter plate 93 to remove residual fine impurities, and then discharged to the alkali adjustment tank 2 through the outlet of the distribution tank 1.

[0036] S2: Slow-release alkalinity adjustment: The pretreated wastewater from step S1 is evenly distributed through the water distributor 14 at the bottom of the alkalinity adjustment tank 2. Under the driving force of the water flow, the water permeates upward through the slow-release functional material 4 (in this embodiment, slow-release limestone particles) within the alkalinity adjustment tank 2. The slow-release functional material 4 slowly releases alkaline substances, which neutralize the acidic components (H+) in the wastewater, adjusting the pH value of the wastewater to 6.5-8.5; simultaneously, if the wastewater contains Fe... 2 Reducing pollutants such as + can be oxidized to Fe(OH)3 flocs under alkaline conditions, thus achieving the oxidative removal of pollutants. During this process, the release rate of the slow-release functional material 4 is controlled at 50-70 mol / (t·d) to ensure stable reaction.

[0037] S3: Sedimentation and separation: The wastewater after the alkali treatment in step S2 is evenly introduced into the sedimentation tank 3 through the water distributor 14 at the bottom of the sedimentation tank 3. Under the action of the inclined tube sedimentation component 11, the reaction product flocs (such as Fe(OH)3, CaSO4, etc.) in the wastewater slide down along the inclined tube and quickly settle to the sludge concentration zone 12 at the bottom of the tank for aggregation and concentration; the supernatant rises along the inclined tube to the outlet area at the top of the sedimentation tank 3.

[0038] S4: Passive hydraulic self-regulating drainage: During the treatment process, the influent flow rate of acidic mine wastewater will fluctuate (2-20m). 3 / d), causing the liquid level in sedimentation tank 3 to change accordingly. At this time, the level gauge in sedimentation tank 3 collects the liquid level signal in real time and transmits it to the controller. The controller, according to the preset liquid level-flow correspondence, controls the actuator to drive the valve core to move, changing the flow cross-sectional area between the valve core and the valve body: when the influent flow rate increases and the liquid level rises, the valve core opening increases, increasing the outfluent flow rate; when the influent flow rate decreases and the liquid level drops, the valve core opening decreases, reducing the outfluent flow rate, achieving 2-20m 3 The system adaptively adjusts the water flow rate based on fluctuations. Simultaneously, the water flow at the outlet drives a hydroelectric generator to supply power to the components of the control mechanism 6. Finally, the treated wastewater (pH 6.5-8.5, suspended solids ≤10mg / L, Fe and Mn content meeting standards) is discharged through the outlet.

[0039] The passive hydraulic self-regulating treatment equipment and method for acidic mine wastewater in this embodiment achieves efficient treatment of acidic mine wastewater through pretreatment in the water distribution tank, slow-release reaction in the alkali adjustment tank, and sedimentation separation in the sedimentation tank. At the same time, by means of a self-feedback system of liquid level monitoring and valve regulation, combined with hydropower generation, passive hydraulic self-regulating operation is achieved, which does not require manual intervention or external power supply. It is suitable for the large fluctuations in the flow rate of mine wastewater and has the advantages of stable operation, low cost, and good treatment effect.

[0040] The following is the water quality of the Junran lead-zinc mine in Nandan County, Hechi City, Guangxi Province, after using the equipment described in this embodiment. The standard is GB25466-2010: using alkaline slow-release material with a slow release rate of 60 mol / (t*d) and observing flow rates of 2~20 m³ / h during dry, normal, and wet seasons. 3 The dimensions were designed based on the d-day variation. The influent and effluent water quality analysis showed that iron and zinc had been removed to the detection limit. This invention creatively optimizes existing treatment technologies to address their weaknesses in responding to fluctuations in water quality and quantity, as well as the high maintenance costs in remote areas. It has the following advantages: It adopts a passive treatment process for acidic mine wastewater, resulting in low operation and maintenance costs and simple operation; passive operation requires zero human intervention, no external power supply, and no manual adjustment of reagent dosage or flow, perfectly adapting to the treatment scenarios of closed mines characterized by "remoteness, power shortages, and difficulty in stationing maintenance personnel." Operation and maintenance costs are reduced by more than 80% compared to traditional active treatment processes and by more than 50% compared to existing passive treatment processes; it has extremely strong adaptability, covering the water inflow changes of the vast majority of closed mines nationwide; long-lasting slow-release materials can be flexibly selected according to specific water quality characteristics (alkaline slow-release materials for acidic inflows, and oxidative slow-release materials for inflows containing reducing heavy metals), achieving precise adaptation to "one mine, one policy"; the three-stage pool can adopt an integrated modular design, prefabricated in the factory and hoisted on-site, or quickly constructed on-site with core control valves installed, with a construction period of ≤15 days; the overall footprint of the device is small, adaptable to narrow mountainous terrain, solving the construction difficulties caused by the "dispersed and complex terrain" of water inflow points in closed mines.

[0041] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics of the solutions is not described in detail here. It will be apparent to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the present invention is defined by the appended claims rather than the foregoing description. Therefore, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A passive hydraulic self-regulating treatment device for acidic mine wastewater, comprising a water distribution tank (1), an alkali adjustment tank (2), and a sedimentation tank (3) connected sequentially along the water flow direction, wherein the alkali adjustment tank (2) is filled with a slow-release functional material (4), characterized in that, The sedimentation tank (3) is equipped with a flow regulating valve (5) at its outlet. The sedimentation tank (3) is equipped with a control mechanism (6). The flow regulating valve (5) includes a valve body and a valve core located inside the valve body. The control mechanism (6) is connected to the valve core.

2. The passive hydraulic self-regulating terminal treatment equipment for acidic mine wastewater according to claim 1, characterized in that, The effective elevation adjustment range of the sedimentation tank (3) is 0.5-2.0 meters, and the adaptive linear flow regulating valve (5) is configured to support 2-20 meters within the elevation adjustment range. 3 / d Water volume fluctuation adjustment.

3. The passive hydraulic self-regulating terminal treatment equipment for acidic mine wastewater according to claim 1, characterized in that, The sustained-release material is an alkaline sustained-release material or an oxidative sustained-release material, and the sustained-release rate of the sustained-release functional material (4) is 50-70 mol / (t·d).

4. The passive hydraulic self-regulating terminal treatment equipment for acidic mine wastewater according to claim 1, characterized in that, The water distribution tank (1) is equipped with a flow guide plate (9) and a pretreatment layer (10), and the pretreatment layer (10) uses crushed stone filter media with a particle size of 5-10mm.

5. The passive hydraulic self-regulating terminal treatment equipment for acidic mine wastewater according to claim 1, characterized in that, The guide plate (9) includes at least a first filter plate (91), a second filter plate (92) and a third filter plate (93). The mesh size of the first filter plate (91) is smaller than that of the second filter plate (92), and the mesh size of the third filter plate (93) is smaller than that of the second filter plate. The pretreatment layer (10) is disposed between the first filter plate (91) and the second filter plate (92).

6. The passive hydraulic self-regulating terminal treatment equipment for acidic mine wastewater according to claim 1, characterized in that, The control mechanism (6) includes a level gauge arranged in the sedimentation tank (3), the level gauge is connected to a controller, an actuator is provided on the valve core, the controller and the actuator are connected, and the controller controls the movement of the actuator to change the valve core opening.

7. The passive hydraulic self-regulating terminal treatment equipment for acidic mine wastewater according to claim 6, characterized in that, The outlet is equipped with a hydroelectric generator, which is connected to the controller.

8. The passive hydraulic self-regulating terminal treatment equipment for acidic mine wastewater according to claim 1, characterized in that, The alkalinity adjustment tank (2) and the sedimentation tank (3) are equipped with water distributors (14). The alkalinity adjustment tank (2) is configured to guide water flow from bottom to top to permeate through the slow-release functional material (4).

9. The passive hydraulic self-regulating terminal treatment equipment for acidic mine wastewater according to claim 8, characterized in that, The sedimentation tank (3) is equipped with an inclined tube sedimentation assembly (11), and the bottom of the sedimentation tank (3) is provided with a sludge thickening zone (12).

10. A passive hydraulic self-regulating treatment method for acidic mine wastewater at the end of the treatment process, based on the passive hydraulic self-regulating treatment equipment for acidic mine wastewater as described in claim 8, characterized in that... Includes the following steps: S1: Pretreatment and diversion: Acidic mine wastewater is introduced into the distribution tank (1). Through the diversion effect of the guide plate (9) in the distribution tank (1), the wastewater flows through the first filter plate (91), the pretreatment layer (10), and the second filter plate (92) in sequence. The crushed stone filter material of the pretreatment layer (10) intercepts large particulate impurities in the wastewater. After secondary filtration by the third filter plate (93), the wastewater is discharged into the distribution tank (1). S2: Slow-release alkalinity adjustment: The wastewater after pretreatment in step S1 is evenly distributed through the water distributor (14) in the alkalinity adjustment tank (2), and the water flow is guided to penetrate from bottom to top through the slow-release functional material (4) in the alkalinity adjustment tank (2). The alkaline or oxidizing substances released by the slow-release functional material (4) react with the acidic components and pollutants in the wastewater to achieve the adjustment of the acidity and alkalinity of the wastewater and the oxidation and removal of pollutants. S3: Sedimentation and separation: The wastewater after the alkali treatment in step S2 is introduced into the sedimentation tank (3) through the water distributor (14). Under the action of the inclined tube sedimentation component (11), the reaction product flocs in the wastewater are rapidly settled to the sludge concentration zone (12) at the bottom of the tank. S4: Passive hydraulic self-regulating drainage: When the liquid level in the sedimentation tank (3) changes with the influent flow rate, the control mechanism (6) transmits the liquid level signal to the valve core, drives the valve core to move, changes the flow cross-sectional area between the valve core and the valve body, and achieves 2-20m 3 The water volume fluctuation is adaptively adjusted, and the final treated wastewater is discharged through the outlet.

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