Multi-section ring flow disposal device and method suitable for abandoned mine drainage

Abstract

This invention discloses a multi-stage circulating treatment device and method suitable for wastewater from abandoned mine shafts, comprising a circulating reaction zone, a sedimentation zone, and a circulating adsorption zone. The circulating reaction zone includes circulating channels I and II. The sedimentation zone is connected to the outlet of the circulating reaction zone, and the circulating adsorption zone is connected to the outlet of the sedimentation zone. The adsorption zone also includes circulating channels III and IV. This invention employs an elliptical baffle plate design, combined with partition plates, to form multiple independent circulating channels, further optimizing and improving the migration path and unsteady-state nature of wastewater within the device. This extends the contact time between the contaminated acidic wastewater and neutralizing and adsorbing materials, resulting in a short-process, multi-contact, highly efficient mine shaft wastewater treatment device and process.

Description

Technical Field

[0001] This invention belongs to the field of mine pollution prevention and control, and specifically relates to a multi-stage circulation treatment device and method for drainage of abandoned mine shafts. Background Technology

[0002] With rapid socio-economic development, the demand for mineral resources has increased dramatically, but mining operations also bring numerous environmental pollution problems. In particular, the large amounts of waste ore left in mine shafts after mining, after prolonged water erosion, oxidation, and other physicochemical processes, generate large quantities of polluted wastewater. Wastewater from copper mine shafts, especially, is highly acidic and contains sulfides and heavy metal ions. Most of these abandoned copper mine shafts have not been effectively controlled, resulting in significant environmental pollution. Therefore, effectively reducing the impact of mine wastewater on the surrounding environment is crucial for mine remediation.

[0003] Currently, there are three main methods for treating mine wastewater: sedimentation, microbial methods, and constructed wetlands. Relatively speaking, sedimentation is the most widely used method due to its simplicity, ease of reactant extraction, and lower cost. Sedimentation combines physical and chemical methods. First, chemical agents are added to the wastewater to increase the alkalinity of acidic wastewater. Then, sulfide agents that readily form heavy metal precipitates are added, converting ionic substances in the water into insoluble or sparingly soluble substances. The precipitates are then removed through sedimentation or mechanical force, thus treating the wastewater. However, the amount of wastewater generated in abandoned mine shafts is uncertain, leading to significant variations in the demand for reagents and other materials. Long-term operation requires even greater reagent consumption, and this method requires dedicated personnel for monitoring. Microbial methods have high requirements for environmental factors in practical applications; excessively high or low temperatures will affect the treatment effect, and the treatment cycle is long. Furthermore, most microorganisms require artificial carbon sources, increasing economic costs. In particular, the uncertainty of mine drainage volume means that microorganisms cannot be quickly adapted to short-term increases in discharge. Constructed wetland methods remove harmful substances from wastewater through the synergistic effect of microorganisms and plants by artificially creating wetland environments. However, constructed wetlands are costly to build, complex to maintain, and their treatment effectiveness is affected by seasonality, making them ineffective in controlling acidic mine drainage. Currently, most domestic patents involving acidic mine wastewater utilize sedimentation and microbial methods. In addition to the aforementioned problems, both methods suffer from low modularity and complex installation.

[0004] Based on the above-mentioned problems, a multi-stage circulation treatment device and method for drainage in abandoned mine shafts has been developed, which helps to ensure the safety of the mine's ecological environment. Summary of the Invention

[0005] To address the problem of insufficient treatment of wastewater discharged from abandoned mine shafts, this invention provides a multi-stage circulating treatment device and method suitable for wastewater from abandoned mine shafts, so as to achieve effective treatment of mine wastewater.

[0006] The technical solution adopted by this invention to solve its technical problem is as follows:

[0007] A multi-stage circulation treatment device suitable for drainage of abandoned mine shafts, including:

[0008] Circulating reaction zone, precipitation zone, circulating adsorption zone;

[0009] The circulating reaction zone is mainly filled with granular limestone; multiple baffles arranged in a zigzag pattern are set at intervals in the circulating reaction zone to form a circulating channel; multiple sequentially connected partitions are installed in the circulating channel to divide the circulating channel into circulating channel I and circulating channel II, and the baffles located on the same side are separated into circulating channels on the corresponding sides.

[0010] The sedimentation zone and the circulatory reaction zone are connected at their effluent outlets, and multiple sieve plates are installed at intervals within the zone. A sludge hopper is installed below each sieve plate.

[0011] The outlet of the circulating adsorption zone is connected to the sedimentation zone, and it is mainly filled with modified zeolite and diatomaceous earth. In the circulating adsorption zone, multiple baffles are also arranged at intervals in a zigzag pattern to form a circulating channel. In the circulating channel, multiple sequentially connected partitions are also installed to divide the circulating channel into circulating channel III and circulating channel IV, and the baffles located on the same side are separated into circulating channels on the corresponding sides.

[0012] Furthermore, circulation channels I and II are connected to inlet I and inlet II respectively; circulation channels III and IV are connected to outlet I and outlet II respectively.

[0013] Furthermore, the barrier plate is an elliptical barrier plate, and the interval between adjacent barrier plates is 0.5 to 1 m, and the partition plate is an arc-shaped partition plate.

[0014] Furthermore, the sieve plate includes a fine-pore sieve plate and a coarse-pore sieve plate spaced apart, with a spacing of 10 cm between them.

[0015] Furthermore, the bottom of the sludge hopper is provided with a single-sided movable sludge unloading plate, and the top of the sludge hopper is provided with a pull-out baffle plate.

[0016] Furthermore, the particle size range of the granular limestone in the circulating reaction zone is 10–40 mm to reduce clogging in the neutralization zone.

[0017] Furthermore, the ratio of modified zeolite to diatomite in the circulating adsorption zone ranges from 3:1 to 6:1.

[0018] Furthermore, the length ratio of the circulating reaction zone to the circulating adsorption zone is 3:2.

[0019] Furthermore, the circulating reaction zone, sedimentation zone, and circulating adsorption zone are all installed in a stainless steel water tank.

[0020] Furthermore, the sedimentation zone is provided with a longitudinal partition that divides it into two parts, with each side of the longitudinal partition connected to a separator plate.

[0021] The present invention also aims to provide a multi-stage circulation treatment method for drainage of abandoned mine shafts, comprising:

[0022] The device is installed at the mine drainage outlet, and the wastewater discharged from the mine enters the device through the pipes from inlet I and inlet II.

[0023] Wastewater flows through the circulating reaction zone and undergoes a neutralization reaction with granular limestone in circulating channel I and circulating channel II to reduce the pH of the acidic wastewater;

[0024] The wastewater with reduced acidity flows through the sedimentation zone, and the resulting flocs settle into the sludge hopper below. When the sludge hopper is full, the water in the sedimentation zone is blocked by a pull-out baffle plate, and then the sludge unloading operation is carried out by opening the movable sludge unloading plate on one side.

[0025] Wastewater flows through the adsorption zone to remove heavy metals, and is then discharged into the environment through outlets I and II.

[0026] The beneficial effects of this invention are as follows:

[0027] 1) This invention is an integrated-multi-stage enhanced treatment process mainly used for the treatment of wastewater discharged from abandoned mine shafts. It has clear structural features, is simple to operate and easy to implement, and can reduce on-site construction difficulty and treatment costs.

[0028] 2) This invention adopts an elliptical barrier plate design, which, together with a partition plate, forms multiple independent circulation channels, thereby optimizing and improving the migration path and unsteady state of wastewater in the device, thus extending the contact time between the contaminated acidic wastewater and the neutralizing and adsorbing materials, forming a short-process, multi-contact, high-efficiency mine wastewater treatment device and process. Attached Figure Description

[0029] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0030] Figure 1 This is a top view of the structure of this multi-stage circulating treatment device;

[0031] Figure 2 This is a schematic diagram of the sedimentation zone structure of this multi-stage circulating treatment device;

[0032] In the picture:

[0033] 1-Inlet I; 2-Inlet II; 3-Front row elliptical baffle plate; 4-Divider plate; 5-Outlet I; 6-Outlet II; 7-Rear row elliptical baffle plate; 8-Circulating adsorption zone; 9-Circulating reaction zone; 10-Stainless steel water tank; 11-Sliding wall; 12-Sedimentation zone; 13-Fine pore screen plate; 14-Coarse pore screen plate; 15-Sludge hopper; 16-Pull-out baffle plate; 17-Single-sided movable sludge discharge plate. Detailed Implementation

[0034] 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.

[0035] In the description of this invention, it should be understood that the terms "upper side", "lower side", "upper end", "both ends", "width", "height", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and 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.

[0036] In this invention, unless otherwise explicitly specified and limited, the terms "set up," "install," "connect," "link," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; a mechanical connection; a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0037] Reference Figures 1-2 This embodiment describes in detail a multi-stage circulation treatment device suitable for drainage from abandoned mine shafts, including:

[0038] Circulating reaction zone 9, precipitation zone 12, circulating adsorption zone 8;

[0039] The circulating reaction zone 9 is mainly filled with granular limestone with a particle size range of 10-40mm to reduce clogging in the neutralization zone. Multiple baffles arranged in a zigzag pattern are set in the circulating reaction zone 9. The baffles are designed as elliptical baffles, divided into front row elliptical baffles 3 and rear row elliptical baffles 7, so that the adjacent elliptical baffles are staggered front-to-back and left-to-right, and the adjacent baffles are spaced 0.5-1m apart, thus forming a circulating channel.

[0040] The circulation channel is equipped with multiple partition plates 4 connected sequentially along the direction of wastewater flow. The partition plates 4 are located at the center of the circulation channel, thereby uniformly dividing the circulation channel into circulation channel I and circulation channel II. At the same time, the barrier plates located on the same side are separated into circulation channels on the corresponding sides. This design can significantly optimize the migration path of mine wastewater in the device and improve the non-steady state of the wastewater.

[0041] The circulation channel I and circulation channel II are connected to the inlet I1 and inlet II2 respectively. When this device is installed at the mine drainage outlet, the wastewater discharged from the mine enters the device through the pipe from inlet I1 and inlet II2.

[0042] The sedimentation zone 12 is connected to the upper end of the outlet of the circulating reaction zone 9, but sealed at the lower end. Water flows through the zone via an overflow method. Multiple sieves are spaced from front to back within the sedimentation zone 12. These sieves include fine-pore sieves 13 and coarse-pore sieves 14 spaced apart at varying heights, with a 10cm interval between them. A sludge hopper 15 is located below the sieves. A single-sided movable sludge discharge plate 17 is installed at the bottom of the sludge hopper 15, and a pull-out baffle plate 16 is installed at the top of the sludge hopper 15. Wastewater in the sedimentation zone 12, blocked by the sieves, will produce flocculent deposits such as calcium sulfate, which will then flow down the sieves into the sludge hopper 15 below. An inclined sliding wall 11 is installed above the sludge hopper 15. When the sludge hopper 15 is full, the water in the sedimentation zone 12 is first blocked by the pull-out baffle plate 16, and then the single-sided movable sludge discharge plate 17 is opened to discharge sludge, ensuring that this operation does not affect the overall operation of the device.

[0043] The upper end of the effluent outlet of the circulating adsorption zone 8 is connected to that of the sedimentation zone 12, while the lower end is sealed. Water is fed through an overflow system. The zone is mainly filled with modified zeolite and diatomaceous earth, with a ratio of 3:1 to 6:1. Multiple baffles arranged in a zigzag pattern are also spaced within the circulating adsorption zone 8, forming a circulating channel. The style and staggered arrangement of the baffles can be referenced from the circulating reaction zone 9. Multiple sequentially connected partition plates 4 are also installed within this circulating channel, uniformly dividing it into circulating channel III and circulating channel IV. Baffles on the same side are separated into circulating channels on corresponding sides. The circulating adsorption zone 8 can remove heavy metals from wastewater, ensuring the effluent standards of the device are met.

[0044] The circulation channels III and IV are connected to drain outlets I5 and II6, respectively.

[0045] In one embodiment, in order to make the separated circulation channel smoother, the partition plate 4 is designed as an arc-shaped partition plate 4 to cooperate with the elliptical barrier plate.

[0046] In one embodiment, to enrich the style of the barrier plate, the barrier plate can also be designed as other shapes that are narrower at the top and wider at the bottom, such as a triangle, as long as it can extend the migration path of wastewater, allow wastewater to pass smoothly, and increase the degree of non-steadiness of wastewater in the circulation channel.

[0047] In one embodiment, the circulating reaction zone 9, sedimentation zone 12, and circulating adsorption zone 8 are all installed within a stainless steel water tank 10, wherein the length ratio of the circulating reaction zone 9, sedimentation zone 12, and circulating adsorption zone 8 is 3:1:2. An openable stainless steel top cover is installed on the stainless steel water tank 10 for easy replacement of packing material and cleaning / maintenance.

[0048] In one embodiment, a longitudinal partition is provided in the middle of the sedimentation zone 12 to divide it into two, and the two sides of the longitudinal partition are respectively connected to the corresponding partition plates 4.

[0049] In one embodiment, the sieve plate is installed at an angle and its tilt angle is adjustable. This design can be flexibly adjusted according to the flow rate or liquid level of the acidic wastewater to be treated: when the flow rate is small or the liquid level is low, the sieve plate can be tilted slightly backward to improve the sieve plate blocking effect and prolong the flocculation and sedimentation time of the wastewater in the sedimentation zone 12; when the flow rate is large or the liquid level is high, the sieve plate can be tilted slightly forward to avoid excessive resistance of the sieve plate, which could cause the wastewater to overflow from the stainless steel tank 10 or flow back into the circulating reaction zone 9, resulting in sediment blockage; based on the flow rate or liquid level sensing device and the precision rack and pinion adjustment device that can be linked to the sieve plate, the tilt angle of the sieve plate can be automatically adjusted.

[0050] This embodiment also provides a multi-stage circulation treatment method suitable for drainage of abandoned mine shafts, including:

[0051] The device is installed at the mine drainage outlet, and the wastewater discharged from the mine enters the device through the pipes from inlet I1 and inlet II2.

[0052] Wastewater flows through the circulating reaction zone 9, where it undergoes a neutralization reaction with granular limestone in circulating channels I and II to reduce the pH of the acidic wastewater.

[0053] The wastewater with reduced acidity flows through the sedimentation zone 12, and the resulting flocs settle into the sludge hopper 15 below. When the sludge hopper 15 is full, the water in the sedimentation zone 12 is blocked by the pull-out baffle plate 16, and then the single-sided movable sludge unloading plate 17 is opened to unload the sludge.

[0054] Wastewater flows through the adsorption zone to remove heavy metals, and is then discharged into the environment through outlets I5 and II6.

[0055] This treatment method is mainly used for the integrated-multi-stage enhanced treatment process of wastewater discharged from abandoned mine shafts. In the process of treating acidic wastewater, it can optimize and improve the migration path and non-steady-state degree of wastewater in the device, forming a short-process, multi-contact, and efficient mine shaft wastewater treatment process.

[0056] Test Example I

[0057] Based on the above concept, a small experimental device was designed in the laboratory: the device is 1m long and contains 5 staggered elliptical baffles. Each circulation unit formed occupies 20cm and is designed in sequence as a limestone neutralization zone and a zeolite adsorption zone.

[0058] Wastewater from a copper mine in southern China was collected. The pH value was 2.5, and the copper concentration was 3.0 mg / L. After treatment by this device, the effluent pH value was 6.6, and the copper concentration was 0.6 mg / L.

[0059] Test Example II

[0060] Trial operation was carried out at the copper mine. After assembly, the unit was transported to the site for installation and testing.

[0061] The stainless steel water tank 10 is 6.0m long, 0.4m wide, and 0.5m high. An elliptical baffle plate and a sedimentation zone 12 are installed inside the stainless steel water tank 10. Granular limestone and modified zeolite are filled into the circulating reaction zone 9 and circulating adsorption zone 8 of the bottom water tank. After filling to a certain height, an arc-shaped partition plate 4 is installed, and granular limestone and modified zeolite are filled into the partitions. The stainless steel top cover is then placed on top. The assembly is now complete. The device is installed at the mine drainage outlet, and wastewater is transported to inlet I1 and inlet II2 through pipelines.

[0062] The wastewater sequentially passes through the circulating neutralization zone, sedimentation zone 12, and circulating adsorption zone 8, with an effluent pH of 6.31 and a copper ion removal rate of 85%.

[0063] It should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-stage circulating treatment device suitable for drainage of abandoned mine shafts, characterized in that, include Circulating reaction zone, precipitation zone, and circulating adsorption zone; The circulating reaction zone is filled with granular limestone; multiple baffles arranged in a zigzag pattern are spaced apart in the circulating reaction zone to form a circulating channel; multiple sequentially connected partitions are installed in the circulating channel to divide the circulating channel into circulating channel I and circulating channel II, and the baffles located on the same side are separated into circulating channels on the corresponding sides. The sedimentation zone is connected to the outlet of the circulating reaction zone, and multiple sieve plates are spaced apart inside it. A sludge hopper is installed below the sieve plates. The effluent end of the circulating adsorption zone is connected to the sedimentation zone, and it is filled with modified zeolite and diatomaceous earth. Multiple baffles arranged in a zigzag pattern are also set at intervals in the circulating adsorption zone to form a circulating channel. Multiple sequentially connected partitions are also installed in the circulating channel to divide the circulating channel into circulating channel III and circulating channel IV, and the baffles located on the same side are separated into circulating channels on the corresponding sides. The barrier plate is an elliptical barrier plate, and the partition plate is an arc-shaped partition plate.

2. The multi-stage circulating treatment device according to claim 1, characterized in that, The circulation channel I and circulation channel II are respectively connected to inlet I and inlet II; The circulation channels III and IV are connected to drain outlet I and drain outlet II respectively.

3. The multi-stage loop treatment device of claim 1, wherein, The spacing between adjacent barrier plates is 0.5~1m.

4. The multi-stage loop treatment device of claim 1, wherein, The sieve plate includes a fine-pore sieve plate and a coarse-pore sieve plate spaced apart, with a spacing of 10 cm between them.

5. The multi-stage loop treatment device of claim 1, wherein, The bottom of the sludge hopper is equipped with a single-sided movable sludge discharge plate, and the top of the sludge hopper is equipped with a pull-out baffle plate.

6. The multi-stage loop treatment device of claim 1, wherein, The particle size range of the granular limestone in the circulating reaction zone is 10~40mm; The ratio of modified zeolite to diatomite in the circulating adsorption zone ranges from 3:1 to 6:

1.

7. The multi-stage circulating treatment device according to claim 1, characterized in that, The circulating reaction zone, sedimentation zone, and circulating adsorption zone are all installed in a stainless steel water tank.

8. A multi-stage circulation disposal method suitable for drainage of a legacy mine, characterised in that, This method is applied to the multi-stage circulating treatment device according to any one of claims 1 to 7, comprising: The device is installed at the mine drainage outlet, and the wastewater discharged from the mine enters the device through the pipes from inlet I and inlet II. Wastewater flows through the circulating reaction zone and undergoes a neutralization reaction with granular limestone in circulating channel I and circulating channel II to reduce the pH of the acidic wastewater; The wastewater with reduced acidity flows through the sedimentation zone, and the resulting flocs settle into the sludge hopper below. When the sludge hopper is full, the water in the sedimentation zone is blocked by a pull-out baffle plate, and then the sludge unloading operation is carried out by opening the movable sludge unloading plate on one side. Wastewater flows through the adsorption zone to remove heavy metals, and is then discharged into the environment through outlets I and II.

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