Acid wastewater treatment system capable of saving earth surface land

Abstract

The invention discloses an acid wastewater treatment system capable of saving earth surface land, and relates to the technical field of wastewater treatment systems, the acid wastewater treatment system comprises an artificial wetland, a limestone drainage channel and an aeration channel; the limestone drainage channel is of a ditch-shaped structure, the top of the limestone drainage channel is provided with a top plate with a closed upper opening, the limestone drainage channel extends around the constructed wetland, the water outlet end of the limestone drainage channel is communicated with the constructed wetland, and the water inlet end of the limestone drainage channel is used for water inflow; the aeration channel is of a ditch-shaped structure, the top of the aeration channel is provided with a top plate with a closed upper opening, the aeration channel extends around the limestone drainage channel, the water outlet end of the aeration channel is communicated with the water inlet end of the limestone drainage channel, and the water inlet end of the aeration channel is used for water inflow. According to the scheme, the utilization rate of earth surface resources can be increased, and the risk of secondary environmental pollution is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment systems, and particularly to an acidic wastewater treatment system that saves surface land use. Background Art

[0002] In the field of acidic wastewater treatment, traditional processes generally adopt a stepped layout of aeration oxidation, chemical precipitation, and constructed wetland in sections. Although pollutant step-by-step reduction can be achieved, the following systematic defects are exposed in engineering practice: waste of land resources and high infrastructure costs. Existing planar layouts require independent facilities such as aeration tanks and sedimentation tanks to be set up, with a large floor area and redundant unit spacing. Statistics show that such layouts result in a land utilization rate of less than 40%, and the pipeline laying length increases by 20% - 30%, significantly pushing up infrastructure costs. The risk of environmental secondary pollution is prominent. Alkaline agents (such as Na(OH)2) diffuse from open limestone drainage ponds and aeration ponds under rainfall scouring. Monitoring data shows that the polluted area with a soil pH > 9.0 around expands by 12% annually. Summary of the Invention

[0003] The object of the present invention is to provide an acidic wastewater treatment system that saves surface land use, so as to solve the problems existing in the above-mentioned prior art, improve the utilization rate of surface resources, and reduce the risk of environmental secondary pollution.

[0004] To achieve the above object, the present invention provides the following solution: The present invention provides an acidic wastewater treatment system that saves surface land use, including: a constructed wetland, a limestone drainage channel, and an aeration channel; the limestone drainage channel is in a ditch-like structure, and the top of the limestone drainage channel has a roof that closes the upper opening. The limestone drainage channel extends around the constructed wetland, and the water outlet end of the limestone drainage channel is communicated with the constructed wetland, and the water inlet end is used for water inlet; the aeration channel is in a ditch-like structure, and the top of the aeration channel has a roof that closes the upper opening. The aeration channel extends around the limestone drainage channel, and the water outlet end of the aeration channel is communicated with the water inlet end of the limestone drainage channel, and the water inlet end of the aeration channel is used for water inlet.

[0005] Preferably, the aeration channel and the limestone drainage channel are arranged in the space below the ground.

[0006] Preferably, the bottom surface of the limestone drainage channel extends downward at an inclination of 5 - 25° from the water inlet end to the water outlet end; the bottom surface of the aeration channel extends downward at an inclination of 5 - 25° from the water inlet end to the water outlet end.

[0007] Preferably, it further includes an electric turning device, which is configured in the limestone drainage channel, and the electric turning device is used to disturb the limestone blocks in the limestone drainage channel.

[0008] Preferably, the diameter D1 of the artificial wetland is 20-50 m, and the water depth is 0.8-1.5 m; the width W1 of the limestone drainage channel is 5-8 m; and the width W2 of the aeration channel is 3-5 m.

[0009] Preferably, an aeration pipe is provided at the bottom of the aeration channel, and a Na(OH)2 automatic dosing pump is provided at the water inlet end of the aeration channel.

[0010] Preferably, it also includes a water reservoir and a backwash system, wherein the water reservoir is used to store purified water from the artificial wetland, and the backwash system includes a backwash pipe and a drive pump, wherein the backwash pipe is pre-buried at the bottom of the limestone drainage channel, and the drive pump is used to pump part of the water in the water reservoir from the backwash pipe to the inside of the limestone drainage channel to backwash the limestone in the limestone drainage channel.

[0011] Preferably, the artificial wetland comprises a gravel layer and a biochar mixed layer arranged in sequence from bottom to top, and the artificial wetland is used for planting reeds and cattails.

[0012] Preferably, a small transport vehicle is further included, which is used to transport limestone blocks through the aeration channel toward the inlet end of the limestone drainage channel. The electric turning device and the bottom surface of the limestone drainage channel are gradually tilted downward from the water inlet end to the water outlet end, and cooperate with each other to achieve the movement of the limestone blocks at the inlet end of the limestone drainage channel toward the water outlet end.

[0013] Preferably, a scraper is also included, which includes a scraper blade, a lifting drive device and a translation drive device. The top of the scraper blade is fixedly connected to the driving end of the lifting drive device, and the lifting drive device is fixedly connected to the driving end of the translation drive device. The lifting drive device can drive the scraper blade to lift and lower, and the translation drive device can drive the lifting drive device to drive the scraper blade to move along the extension direction of the bottom plate of the aeration channel.

[0014] Compared with the prior art, the present invention has achieved the following technical effects: This invention utilizes a unique arrangement of artificial wetlands, limestone drainage channels, and aeration channels to create a compact overall system architecture, reducing floor space and improving the utilization of surface resources. This makes it particularly suitable for use in areas with limited surface area. Furthermore, both the limestone drainage channels and aeration channels in this application are enclosed channel structures, which reduces the risk of secondary environmental pollution. Furthermore, the enclosed structure reduces oxygen content, thereby slowing the oxidation rate of limestone within the limestone drainage channels and reducing maintenance costs.

[0015] Furthermore, the aeration channels and limestone drainage channels in the present invention are arranged in the space below the ground, so that only the constructed wetland exists on the ground surface, thereby further reducing the surface area used. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0017] Figure 1 Top view of the acidic wastewater treatment system for saving surface land provided by the embodiment of the present invention; Figure 2 Vertical cross-sectional schematic diagram of the acidic wastewater treatment system for saving surface land provided by the embodiment of the present invention; Figure 3 Vertical cross-sectional schematic diagram of the constructed wetland; Figure 4 Partial structural schematic diagram of the electric turning device; Figure 5 Structural schematic diagram of the sludge scraper.

[0018] In the figure: 1 - constructed wetland; 2 - limestone drainage channel; 3 - aeration channel; 4 - acidic wastewater collection pool; 5 - mud sump; 6 - detection point; 7 - drain pipe; 8 - exhaust pipe; 9 - aeration pipe; 10 - gravel layer; 11 - biochar mixed layer; 12 - turning chain; 13 - rotary drive motor; 14 - drive chain; 15 - rack; 16 - driving gear; 17 - integrated body; 18 - lifting drive device; 19 - carriage; 20 - slide rail; 21 - sludge scraping plate; 22 - water injection pipe. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0020] The purpose of the present invention is to provide an acidic wastewater treatment system for saving surface land to solve the problems existing in the above-mentioned prior art, improve the utilization rate of surface resources, and reduce the risk of environmental secondary pollution.

[0021] To make the above objects, features, and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] First, some technical terms involved in the embodiments of the present application are introduced.

[0023] An artificial wetland is an ecological engineering system designed and constructed artificially by simulating the structure and function of a natural wetland ecosystem, mainly used for sewage treatment, water purification, ecological restoration, and landscape creation. Its core principle is to utilize the physical, chemical, and biological synergistic effects among plants, microorganisms, substrates (such as soil and gravel), and water bodies in the wetland to achieve efficient removal of pollutants and ecological circulation.

[0024] The following Figures 1 to 5 describes the embodiments of the present invention.

[0025] The present invention provides an acidic wastewater treatment system that saves surface land use, including: an artificial wetland 1, a limestone drainage channel 2, and an aeration channel 3; the limestone drainage channel 2 is in a ditch-like structure, and the top of the limestone drainage channel 2 has a roof that closes the upper opening. The limestone drainage channel 2 extends around the artificial wetland 1. The water outlet end of the limestone drainage channel 2 is connected to the artificial wetland 1, and the water inlet end is used for water inlet; the aeration channel 3 is in a ditch-like structure, and the top of the aeration channel 3 has a roof that closes the upper opening. The aeration channel 3 extends around the limestone drainage channel 2. The water outlet end of the aeration channel 3 is connected to the water inlet end of the limestone drainage channel 2, and the water inlet end of the aeration channel 3 is used for water inlet.

[0026] A certain height of limestone blocks is stacked in the limestone drainage channel 2, and the limestone blocks are used to neutralize the acidic substances in the acidic wastewater and adjust its pH value.

[0027] The present invention uses a special arrangement of the artificial wetland 1, the limestone drainage channel 2, and the aeration channel 3 to make the entire system structure compact, reduce the floor area, and improve the utilization rate of surface resources, which is particularly suitable for use in areas with limited surface area. In addition, both the limestone drainage channel 2 and the aeration channel 3 in the present application are closed-channel structures, which can reduce the risk of environmental secondary pollution. In addition, the closed structure reduces the oxygen content, thereby reducing the oxidation rate of limestone in the limestone drainage channel and further reducing the maintenance cost.

[0028] In some embodiments, an acidic wastewater collection pool 4 is further included. The acidic wastewater collection pool 4 is used to collect acidic wastewater, and the acidic wastewater collection pool 4 is connected to the water inlet end of the aeration channel 3.

[0029] In some embodiments, a drain pipe 7 is also connected to one side of the constructed wetland 1. The drain pipe 7 is used to discharge the clarified water purified by the constructed wetland to a designated location, such as a reservoir. The drain pipe 7 is connected with a bypass, and the bypass diverts the water in the drain pipe 7 to the detection point 6 for detection. If the detected water quality meets the standard, it is discharged into the clean water reservoir; if the detected water quality does not meet the standard, it is discharged into the waste water tank.

[0030] In some embodiments, an exhaust pipe 8 communicating with the atmosphere is provided on the top plate of the aeration channel 3.

[0031] In some embodiments, the aeration channel 3 and the limestone drainage channel 2 are arranged in the space below the ground.

[0032] In this embodiment, the aeration channel 3 and the limestone drainage channel 2 are arranged in the space below the ground, so that only the constructed wetland 1 exists on the ground surface, thereby further reducing the land use area on the ground surface.

[0033] In some embodiments, the bottom surface of the limestone drainage channel 2 extends downward at an inclination of 5 - 25° from the water inlet end to the water outlet end, preferably 20°; the bottom surface of the aeration channel 3 extends downward at an inclination of 5 - 25° from the water inlet end to the water outlet end, preferably 20°.

[0034] In this embodiment, by setting the bottom surfaces of the limestone drainage channel 2 and the aeration channel 3 to extend downward obliquely, the waste water therein can flow by gravity to the downstream constructed wetland 1.

[0035] In some embodiments, the embodiment of the present invention further includes an electric turning device, which is arranged in the limestone drainage channel 2, and the electric turning device is used to disturb the limestone blocks in the limestone drainage channel 2.

[0036] In this embodiment, the electric turning device is used to turn the limestone blocks in the limestone drainage channel 2 regularly to prevent them from caking. After caking, the passing property of the waste water in the limestone drainage channel 2 will be reduced, and thus its treatment efficiency will be reduced. However, this application can prevent caking, and thus can maintain the treatment efficiency of the waste water treatment system.

[0037] Specifically, the electric turning device includes a turning chain 12 and a chain driving device. The turning chain 12 is arranged inside the limestone drainage channel 2 and extends along the extension direction of the limestone drainage channel 2. The turning chain 12 is buried in the limestone blocks, and the chain driving device can drive the turning chain 12 to vibrate or rotate to disturb the limestone blocks to avoid caking.

[0038] Specifically, the chain driving device can be set according to the actual situation. For example, as Figure 4As shown, it can be driven by multiple vertically and / or horizontally arranged drive chains 14, crankshafts, and rotary drive motors 13. The multiple drive chains 14 are arranged in sequence along the extension direction of the turning chain 12. Adjacent two, three, or four drive chains 14 are respectively arranged at different positions of the turning chain 12. One drive chain 14 corresponds to one rotary drive motor 13 and one crankshaft. The rotary drive motor 13 drives the crankshaft to rotate. One end of the crankshaft and the drive chain 14 away from the turning chain 12 are hinged so as to drive the drive chain 14 to move along the direction away from and close to the turning chain 12, thereby driving the turning chain 12 to move in three-dimensional space, and further achieving the purpose of disturbing the stones. Figure 4 In it, the circular symbol with a + sign represents a bidirectional arrow up and down.

[0039] In some examples, the period of turning the limestone blocks in the limestone drainage channel 2 is set according to the actual usage situation. For example, in some cases, it can be turned once every quarter.

[0040] In some embodiments, the diameter D1 of the constructed wetland 1 is 20 - 50 m, and the water depth is 0.8 - 1.5 m; the width W1 of the limestone drainage channel 2 is 5 - 8 m; the width W2 of the aeration channel 3 is 3 - 5 m.

[0041] This embodiment provides the sizes of the various units in the specific acidic wastewater treatment system. It can be understood that in some examples, when the available land area is small, the constructed wetland 1, the width of the limestone drainage channel 2, and the width of the aeration channel 3 can also be set smaller.

[0042] In some embodiments, the heights of both the limestone drainage channel 2 and the aeration channel 3 are above 1 m, preferably 1.5 m, and can also be set to about 2 m when necessary.

[0043] In some embodiments, an air diffuser pipe 9 is provided at the bottom of the aeration channel 3, and a Na(OH)2 automatic dosing pump is provided at the water inlet end of the aeration channel 3.

[0044] This embodiment realizes the automatic dosing of the Na(OH)2 reagent, and the Na(OH)2 reagent is used to adjust the pH value of the wastewater and neutralize the acidic wastewater.

[0045] In some embodiments, the embodiment of the present invention further includes a reservoir and a backwashing system. The reservoir is used to store the water purified by the constructed wetland 1. The backwashing system includes a backwashing pipe and a driving pump. The backwashing pipe is buried at the bottom of the limestone drainage channel 2, and the driving pump is used to pump a part of the water in the reservoir from the backwashing pipe into the limestone drainage channel 2 to backwash the limestone in the limestone drainage channel 2.

[0046] In this embodiment, a backwashing system is used to spray high-pressure cleaning water into the limestone drainage channel 2, so as to achieve the purpose of cleaning the limestone blocks. In addition, this application does not require an external water source and can directly use the water source in the self-owned reservoir in the wastewater treatment system.

[0047] Specifically, the backwashing pipe is a pipeline with a diameter of DN100 and an opening rate of 15%. In actual implementation, high-pressure water flushing is carried out twice a week (pressure 0.4MPa, flow rate 50m³ / h, lasting for 10 minutes).

[0048] In some embodiments, the constructed wetland 1 includes a gravel layer 10 and a biochar mixed layer 11 arranged in sequence from bottom to top. Reed and cattail are planted in the constructed wetland 1.

[0049] The gravel layer 10 and the biochar mixed layer 11 in this embodiment can be called the filler layer. In a specific example, the particle size of the lower gravel layer 10 is 3 - 5cm, with a thickness of 50cm, and the proportion of biochar in the upper biochar mixed layer 11 is 25%, with a thickness of 100cm.

[0050] In the actual implementation process, microorganisms also need to be added into the constructed wetland 1, such as: sulfate-reducing bacteria (SRB) agent (dosage 2kg / m², viable bacteria count ≥ 10 8 CFU / g) The plant configuration of the constructed wetland 1 is: reed (18 plants / m²) + cattail (10 plants / m²), and the root depth is 60 - 80cm.

[0051] A water injection pipe 22 is arranged at the bottom of the constructed wetland 1.

[0052] In some embodiments, the embodiment of the present invention further includes a small transport vehicle, which is used to transport limestone blocks to the inlet end of the limestone drainage channel 2 through the aeration channel 3. The electric turning device and the bottom surface of the limestone drainage channel 2 gradually slope downward from the water inlet end to the water outlet end to cooperate to realize the transportation of the limestone blocks at the inlet end of the limestone drainage channel 2 in the direction of the water outlet end.

[0053] The solution provided by the embodiment of the present invention realizes the purpose of replenishing limestone blocks into the limestone drainage channel 2, and fully utilizes the two solutions of the electric turning device and the fact that the bottom surface of the limestone drainage channel 2 gradually slopes downward from the water inlet end to the water outlet end, so that the entire system does not need to add additional transportation equipment, and the transportation of limestone blocks can be directly realized by the cooperation of the electric turning device and the fact that the bottom surface of the limestone drainage channel 2 gradually slopes downward from the water inlet end to the water outlet end.

[0054] The particle size of the limestone blocks in this embodiment is 8 - 12cm, and the CaCO3 content in the limestone blocks is ≥ 90%.

[0055] Embodiment Two The embodiment of the present invention provides another acidic wastewater treatment system for saving surface land use. Different from the first embodiment, a sludge scraper is added on the basis of the first embodiment in this embodiment. The sludge scraper includes a sludge scraping plate 21, a lifting drive device 18 and a translation drive device. The top of the sludge scraping plate 21 is fixedly connected to the drive end of the lifting drive device 18, and the drive end of the lifting drive device 18 is fixedly connected to the drive end of the translation drive device. The lifting drive device 18 can drive the sludge scraping plate 21 to lift, and the translation drive device can drive the lifting drive device 18 to drive the sludge scraping plate 21 to move along the extension direction of the bottom plate of the aeration channel 3.

[0056] Specifically, the translation drive device includes an arc-shaped rack 15 arranged on the top of the aeration channel 3, a carriage 19, a slide rail 20 arranged on the side wall of the aeration channel 3, a driving gear 16, a driving motor and a speed reducer. The driving motor, the speed reducer and the driving gear 16 are connected in sequence. The rack 15 has the same extension trajectory as the bottom plate of the aeration channel 3, only the height is different, that is, the vertical distance between the rack 15 and the bottom plate of the aeration channel 3 is the same everywhere. The driving gear 16 meshes with the rack 15. The driving motor and the speed reducer are integrated into an integrated body 17. The lifting drive device 18 is a linear electric cylinder, which is fixedly connected to the integrated body 17 through a carriage 19. The carriage 19 is slidably connected to the slide rail 20 arranged on the side wall of the aeration channel 3. The slide rail 20 has the same extension trajectory as the bottom plate of the aeration channel 3, only the height is different, that is, the vertical distance between the slide rail 20 and the bottom plate of the aeration channel 3 is the same everywhere. In this way, the driving motor can be used to drive the carriage 19 and the lifting drive device 18 and the sludge scraping plate 21 thereon to move along the extension direction of the bottom plate, so as to achieve the purpose of scraping the sludge outwards.

[0057] In addition, the lifting drive device 18 in this embodiment can also drive the sludge scraping plate 21 to lift to adjust its height, and adjust the height of the sludge scraping plate 21 according to different usage scenarios. For example, when the sludge at the bottom of the aeration channel 3 is thick, in order to avoid the situation that the power of the drive motor is insufficient to scrape the overly thick sludge, the sludge scraping plate 21 can be adjusted to descend so that there is a certain interval between its bottom edge and the bottom surface of the aeration channel 3. After scraping the upper layer of sludge first, then gradually lower the sludge scraping plate 21, thereby achieving the purpose of scraping sludge in layers. In addition, when the sludge is scraped to the water inlet end of the aeration channel 3, the sludge scraping plate 21 needs to return to the water outlet end of the aeration channel 3 before scraping the sludge again. Before returning, the sludge scraping plate 21 is lifted to a certain height in advance, thereby avoiding the sludge scraping plate 21 scraping the sludge back to the inside of the aeration channel 3. In order to avoid damage to the sludge scraper due to excessive water level in the aeration channel 3, it is necessary to design the electrical components in the sludge scraper for waterproofing, or after scraping the sludge, lift the sludge scraping plate 21 to a certain height and drive the lifting drive device 18 and the sludge scraping plate 21 to move outward to the outside of the water inlet end of the aeration channel 3, thereby avoiding damage to components such as the lifting device in the standby state due to excessive water level in the aeration channel 3.

[0058] In some embodiments, the air diffuser pipe 9 at the bottom of the aeration channel 3 is buried below the bottom surface of the aeration channel 3. In this case, the bottom surface of the aeration channel 3 is a flat structure. Therefore, the bottom edge of the sludge scraping plate 21 can be set to extend along a straight line.

[0059] In other embodiments, if the air diffuser pipe 9 at the bottom of the aeration channel 3 is placed above the bottom surface of the aeration channel 3, the bottom edge of the sludge scraping plate 21 needs to be set in a grooved style so that the air diffuser pipe 9 is located in the groove, thereby avoiding the situation that the bottom edge of the sludge scraping plate 21 cannot contact the bottom surface of the aeration channel 3 due to the presence of the air diffuser pipe 9 and avoiding the influence of the setting of the air diffuser pipe 9 on the sludge scraping process.

[0060] In some embodiments, a sludge sump 5 is provided on the outside (i.e., the water inlet end) of the aeration channel 3, and the sludge sump 5 is used to temporarily store the sludge scraped from the inside of the aeration channel 3.

[0061] Embodiment III An embodiment of the present invention provides another acidic wastewater treatment system that saves surface land use. Different from the first embodiment, a sludge scraper is added to this embodiment on the basis of the first embodiment. The sludge scraper is an automatically operated or manually driven sludge scraper vehicle, and a sludge scraping plate is provided at its bottom. When in use, it is necessary to control or manually drive the sludge scraper vehicle to walk into the aeration channel 3 and reach the innermost side (i.e., the water outlet end), then lower the sludge scraping plate, and finally control or manually drive the sludge scraper vehicle to walk towards the outer side (i.e., the water inlet end) of the aeration channel 3. A sludge sump 5 is dug on the outer side of the aeration channel 3. While the sludge scraper vehicle walks towards the outer side of the aeration channel 3, the sludge scraping plate will scrape the sludge at the bottom of the aeration channel 3 towards the outer side, and finally the sludge can be scraped into the outer sludge sump 5.

[0062] It can be understood that the height and width of the sludge scraper vehicle need to be smaller than the height and width of the aeration channel 3 to facilitate the smooth operation of the sludge scraper vehicle inside the aeration channel 3. In addition, considering the slope of the bottom surface and the presence of sludge, anti-slip tires need to be set when implementing this embodiment, and anti-slip chains need to be added if necessary.

[0063] Specific examples are applied in the present invention to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An acidic wastewater treatment system for saving surface land use, characterized in that: include: artificial wetlands; A limestone drainage channel is a ditch-like structure having a top plate that closes an upper opening. The limestone drainage channel extends around the artificial wetland. The water outlet of the limestone drainage channel is connected to the artificial wetland, and the water inlet is used for water intake. The aeration channel is a ditch-like structure with a top plate that closes the upper opening. The aeration channel extends around the limestone drainage channel. The water outlet of the aeration channel is connected to the water inlet of the limestone drainage channel. The water inlet of the aeration channel is used for water intake.

2. The acid wastewater treatment system for saving surface land use according to claim 1, characterized in that: The aeration channel and the limestone drainage channel are arranged in a space below the ground.

3. The acid wastewater treatment system for saving surface land use according to claim 1, wherein: The bottom surface of the limestone drainage channel extends downward at an angle of 5 to 25 degrees from the water inlet end to the water outlet end; the bottom surface of the aeration channel extends downward at an angle of 5 to 25 degrees from the water inlet end to the water outlet end.

4. The acid wastewater treatment system for saving surface land use according to claim 1, characterized in that: It also includes an electric turning device, which is arranged in the limestone drainage channel and is used to disturb the limestone blocks in the limestone drainage channel.

5. The acid wastewater treatment system for saving surface land use according to claim 1, characterized in that: The diameter D1 of the artificial wetland is 20-50m, and the water depth is 0.8-1.5m; the width W1 of the limestone drainage channel is 5-8m; and the width W2 of the aeration channel is 3-5m.

6. The acid wastewater treatment system for saving surface land use according to claim 1, characterized in that: An aeration pipe is provided at the bottom of the aeration channel, and a Na(OH)2 automatic dosing pump is provided at the water inlet end of the aeration channel.

7. The acid wastewater treatment system for saving surface land use according to claim 1, characterized in that: It also includes a water reservoir and a backwash system, wherein the water reservoir is used to store purified water from the artificial wetland, and the backwash system includes a backwash pipe and a drive pump, wherein the backwash pipe is pre-buried at the bottom of the limestone drainage channel, and the drive pump is used to pump part of the water in the water reservoir from the backwash pipe to the inside of the limestone drainage channel to backwash the limestone in the limestone drainage channel.

8. The acid wastewater treatment system for saving surface land use according to claim 1, characterized in that: The artificial wetland comprises a gravel layer and a biochar mixed layer arranged in sequence from bottom to top, and the artificial wetland is used for planting reeds and cattails.

9. The acid wastewater treatment system for saving surface land use according to claim 4, characterized in that: It also includes a small transport vehicle, which is used to transport limestone blocks through the aeration channel toward the inlet end of the limestone drainage channel. The electric turning device and the bottom surface of the limestone drainage channel, which is gradually inclined downward from the water inlet end to the water outlet end, cooperate to achieve the movement of the limestone blocks at the inlet end of the limestone drainage channel toward the water outlet end.

10. The acid wastewater treatment system for saving surface land use according to claim 1, characterized in that: It also includes a scraper, which includes a scraper blade, a lifting drive device and a translation drive device. The top of the scraper blade is fixedly connected to the driving end of the lifting drive device, and the lifting drive device is fixedly connected to the driving end of the translation drive device. The lifting drive device can drive the scraper blade to lift and lower, and the translation drive device can drive the lifting drive device to drive the scraper blade to move along the extension direction of the bottom plate of the aeration channel.

Images