Anti-blocking subsurface flow constructed wetland equipment
By adopting a layered structure and directional impurity recirculation design in the subsurface flow constructed wetland equipment, the problems of equipment blockage and low purification efficiency are solved, and the long-term, high-efficiency operation and low-cost operation and maintenance of the equipment are achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- RIZHAO ENVIRONMENTAL PROTECTION RES INST CO LTD
- Filing Date
- 2026-03-13
- Publication Date
- 2026-05-12
AI Technical Summary
Existing subsurface flow constructed wetland equipment is prone to clogging during operation, its purification efficiency decreases over time, its operation and maintenance costs are high, and it lacks effective impurity interception and diversion design, resulting in uneven water flow and some sewage not being in sufficient contact with the substrate, thus resulting in low purification efficiency.
A clog-resistant subsurface flow constructed wetland device was designed, which adopts a top-down layered shell structure, including an overflow layer, a solid flow layer and a guide layer. Combined with a sedimentation tank, a water distribution pipe and a return pipe, it achieves directional return and uniform infiltration of impurities through gravity sedimentation, plant strips and gravel filling, ensuring full contact between sewage and substrate and avoiding impurity accumulation.
It effectively solves the clogging problem of subsurface flow constructed wetlands, extends the fault-free operation cycle of equipment, reduces operation and maintenance costs, improves purification efficiency and equipment operation stability, and achieves efficient wastewater treatment.
Smart Images
Figure CN122010307A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of constructed wetland technology, specifically to a clog-resistant subsurface flow constructed wetland device. Background Technology
[0002] Subsurface flow constructed wetlands, with their advantages of being eco-friendly, having low operation and maintenance costs, and providing comprehensive purification effects, have become an important technology for treating urban domestic sewage, rural decentralized sewage, and industrial light wastewater, and are widely used in the field of water environment management. However, their core structure and water flow control design have inherent defects, leading to frequent clogging problems in actual operation, and the purification efficiency rapidly declines with operating time, significantly shortening the equipment's trouble-free operating cycle and increasing the operation and maintenance costs of dredging and substrate replacement. These defects have become the constraints on the large-scale and long-term application of subsurface flow constructed wetlands.
[0003] The influent pretreatment process in existing subsurface flow constructed wetlands is poorly designed, often lacking precise flow guidance and interception structures. Sludge and large suspended particles in the wastewater can easily enter the wetland substrate layer, creating a potential for sedimentation at the source. Simultaneously, the water distribution system lacks a uniform distribution design, easily leading to localized excessively fast or stagnant flow. Under these conditions, excessively fast flow can erode the substrate, causing the packing material to be lost, while stagnant flow can easily create an anaerobic environment, leading to excessive growth of microbial biofilms that adhere to the substrate pore surface, gradually causing substrate compaction and blocking water infiltration channels.
[0004] Secondly, the existing equipment's bottom water collection and diversion structure lacks a matching design for directional sludge discharge. Small particulate impurities carried by sewage during infiltration tend to accumulate at the bottom layer and cannot be effectively collected and discharged, forming a hardened layer over time, which further exacerbates the blockage. Although some are equipped with diversion pipes, the pipes are poorly matched with the particle size of the bottom filler, which can easily lead to gravel blocking and perforation of the pipes. Moreover, the diversion pipes lack precise power and structural guidance, making it impossible to achieve directional backflow and collection of impurities, and instead becoming new accumulation points.
[0005] Furthermore, existing subsurface flow constructed wetlands lack diversion and level adaptation designs, making them prone to short-circuiting issues. Some wastewater is discharged rapidly without sufficient contact with plant roots and substrate, significantly reducing purification efficiency. Simultaneously, the sedimentation tank and flow guiding structure are poorly connected, lacking backflow prevention designs, allowing collected impurities to easily flow back into the flow guiding layer. Moreover, the sludge removal system is often a crude design, resulting in incomplete sludge removal. Blockages necessitate excavation and cleaning of the constructed wetland equipment, increasing maintenance difficulty and severely impacting the overall operational stability. Therefore, designing a subsurface flow constructed wetland system that can solve the blockage problem at its source has become an urgent industry need. Summary of the Invention
[0006] Therefore, it is necessary to provide a clog-resistant subsurface flow constructed wetland device to address the existing technical problems.
[0007] To solve the problems of the prior art, the technical solution adopted by the present invention is as follows:
[0008] A clog-resistant subsurface flow constructed wetland device, comprising:
[0009] The shell has an inlet channel at one end and an outlet at the other end. The middle of the shell has an overflow layer for intercepting debris and draining water, a solid flow layer for stabilizing flow and infiltration, and a flow guiding layer for collecting and guiding water in sequence from top to bottom. Overflow holes for drainage are arranged at equal intervals on both sides of the shell. Three plant strips with their upper ends penetrating the overflow layer are planted along the long side of the solid flow layer.
[0010] The lower end of the inlet channel is equipped with a sedimentation hopper for collecting silt. The middle part of the sedimentation hopper is connected to the overflow layer. The lower part of the sedimentation hopper is connected to an inclined water distribution pipe that penetrates the guide layer. The lower end of the water distribution pipe is connected to the sedimentation hopper. The two sides of the water distribution pipe are connected to return water pipes that divert and guide the water flow in an equally spaced array. The return water pipes are provided with perforations for water return in an equally spaced array.
[0011] The flow guide layer is filled with gravel that wraps the water distribution pipe and the return pipe. After the water flows from top to bottom through the overflow layer, the solid flow layer and the flow guide layer, the impurities in the water flow back to the sedimentation tank through the return pipe and the water distribution pipe.
[0012] Furthermore, two sludge pumps are installed at one end of the shell near the water inlet channel, and the input ends of the two sludge pumps are respectively connected to the lower part of the sedimentation hopper.
[0013] Furthermore, a diversion plate is installed at the lower end of the inlet channel. The upper part of the diversion plate is inclined, and the upper part of the diversion plate covers the connection between the sedimentation tank and the solid flow layer to prevent the sewage injected through the upper end of the sedimentation tank from flowing directly into the solid flow layer.
[0014] Furthermore, a flow stop cover is installed on the side of the sedimentation hopper away from the water distribution pipe, and the flow stop cover is coaxial with the return water pipe.
[0015] The upper end of the flow stop cover is hinged to the sedimentation hopper by a torsion spring. When the flow stop cover is impacted by the water flow, it deflects to the side away from the water distribution pipe.
[0016] Furthermore, a perforated plate is provided on the side of the water inlet channel. The perforated plate is fixed to the inner wall of the shell. The perforated plate has through holes along its long side for the plants of the three plant belts to pass through.
[0017] Furthermore, an overflow plate is slidably installed on the side of the overflow hole near the perforated plate;
[0018] A plastic hollow pipe is fixed to the middle of the overflow plate. The water overflowing to the upper part of the perforated plate pushes the plastic hollow pipe upward.
[0019] Furthermore, an overflow plate is installed at the upper end of the perforated plate near the water inlet channel, and guide pins are arranged in an equidistant array along the circumference of the overflow plate, and the guide pins are fixedly connected to the perforated plate.
[0020] A spring is coaxially sleeved on the guide pin. The upper end of the spring is fixedly connected to the upper end of the guide pin, and the lower end is fixedly connected to the upper end of the overflow plate.
[0021] Furthermore, three planting pots are arranged in an array along the long side at the lower end of the perforated plate, and the lower end of the planting pots is provided with connecting holes at equal intervals.
[0022] Furthermore, a keel plate is provided at the lower end of the planting pot, which is fixed to the shell. An impermeable membrane is provided at the upper end of the keel plate, which abuts against the lower end of the planting pot.
[0023] Furthermore, a filter screen is installed on the side of the water outlet near the planting pot to intercept impurities in the water.
[0024] The beneficial effects of this invention compared to the prior art are:
[0025] Firstly, this equipment effectively solves the technical defects of existing subsurface flow constructed wetland pretreatment, such as extensive methods and easy clogging of the bottom layer. Through the layered and coordinated overflow layer, solid flow layer and guide layer set from top to bottom of the shell, together with the sedimentation hopper at the bottom of the inlet channel, it intercepts and settles floating debris, silt and large particles in the sewage from the source, preventing impurities from entering the subsequent layered structure and causing siltation hazards. At the same time, the gravel filled in the guide layer wraps the water distribution pipe and return pipe. Combined with the inclined setting of the water distribution pipe and the perforated design of the return pipe, the impurities are directed back to the sedimentation hopper, forming a closed loop of sludge discharge. This completely solves the problem of bottom impurity accumulation and compaction, extends the equipment's trouble-free operation cycle, and reduces dredging and maintenance costs.
[0026] Secondly, this equipment addresses the technical shortcomings of existing subsurface flow constructed wetlands, such as uneven water distribution, susceptibility to short-circuiting, and reduced purification efficiency. Through the synergistic design of the overflow layer for debris interception and drainage, the solid flow layer for stable infiltration and ecological protection with plant belts, and the guide layer for directional flow, it ensures uniform sewage infiltration without local stagnation or scouring. This allows sewage to fully contact plant roots and substrate, improving purification efficiency. At the same time, the sedimentation tank connects smoothly with the distribution and return pipes, enabling directional collection of impurities and preventing secondary blockages caused by backflow. The overflow holes on both sides of the shell are suitable for flood drainage during the rainy season, ensuring the stability of equipment operation. It eliminates the need for frequent substrate replacement and is easy to maintain. Attached Figure Description
[0027] Figure 1 This is a three-dimensional structural diagram of an embodiment;
[0028] Figure 2 This is a three-dimensional half-sectional view of the embodiment;
[0029] Figure 3 yes Figure 2 Enlarged view of the structure at point A in the middle;
[0030] Figure 4 yes Figure 2 Enlarged view of the structure at point B in the middle;
[0031] Figure 5 yes Figure 2 Enlarged view of the structure at point C;
[0032] Figure 6 This is an exploded three-dimensional structural diagram of the embodiment;
[0033] Figure 7 yes Figure 6 Enlarged view of the structure at point D;
[0034] Figure 8 yes Figure 6 Enlarged view of the structure at point E in the middle.
[0035] The numbers on the map are:
[0036] 1. Shell; 2. Inlet channel; 3. Drainage plate; 4. Sedimentation hopper; 5. Flow stop cover; 6. Sludge pump; 7. Water distribution pipe; 8. Return pipe; 9. Overflow layer; 10. Perforated plate; 11. Overflow tray; 12. Guide pin; 13. Overflow plate; 14. Overflow hole; 15. Plastic hollow pipe; 16. Solid flow layer; 17. Planting strip; 18. Planting pot; 19. Connection hole; 20. Flow guide layer; 21. Impermeable membrane; 22. Keel plate; 23. Outlet; 24. Filter screen. Detailed Implementation
[0037] To further understand the features, technical means, and specific objectives and functions achieved by the present invention, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.
[0038] refer to Figures 1 to 8 A clog-resistant subsurface flow constructed wetland device, comprising:
[0039] The shell 1 has an inlet channel 2 at one end and an outlet 23 at the other end. The middle of the shell 1 has an overflow layer 9 for intercepting debris and draining water, a solid flow layer 16 for stabilizing flow and infiltration, and a flow guiding layer 20 for collecting and guiding water from top to bottom. Overflow holes 14 for drainage are arranged at equal intervals on both sides of the shell 1. The solid flow layer 16 has three plant strips 17 with their upper ends passing through the overflow layer 9 along its long side.
[0040] The lower end of the inlet channel 2 is provided with a sedimentation hopper 4 for collecting silt. The middle part of the sedimentation hopper 4 is connected to the overflow layer 9. The lower part of the sedimentation hopper 4 is connected to a water distribution pipe 7 that is inclined and penetrates the guide layer 20. The lower end of the water distribution pipe 7 is connected to the sedimentation hopper 4. The two sides of the water distribution pipe 7 are connected to return water pipes 8 that divert and guide the water body in an equally spaced array. The return water pipes 8 are provided with perforations for water body return in an equally spaced array.
[0041] The guide layer 20 is filled with gravel that wraps the water distribution pipe 7 and the return pipe 8. After the water flows from top to bottom through the overflow layer 9, the solid flow layer 16 and the guide layer 20, the impurities in the water flow back to the sedimentation tank 4 through the return pipe 8 and the water distribution pipe 7.
[0042] During operation, wastewater first enters the equipment through the inlet channel 2 at one end of the shell 1. At this point, the sedimentation hopper 4 at the lower end of the inlet channel 2 utilizes gravity settling to quickly collect most of the sludge and large particulate impurities carried in the wastewater, preventing easily accumulating substances from entering the subsequent stratified structure and reducing the overall risk of blockage. Simultaneously, the overflow layer 9 at the top center of the shell 1 simultaneously performs a dual anti-blocking function, intercepting floating debris such as fallen leaves and other objects on the wastewater surface to prevent them from clogging the lower pores. When the water level is too high during the rainy season, the overflow holes 14, evenly spaced on both sides of the shell 1, open simultaneously to quickly drain excess water, preventing long-term water accumulation in the bed and the formation of an anaerobic environment. This avoids excessive growth of the microbial film and sludge accumulation, providing stable operating conditions for subsequent filtration processes. The pretreated wastewater then flows evenly into the overflow layer 9 through the connection between the sedimentation hopper 4 and the overflow layer 9, smoothly transitioning to the next filtration stage.
[0043] After passing through the overflow layer 9 from top to bottom, the wastewater enters the middle solid flow layer 16, where it completes core filtration and prevents clogging. Three plant strips 17, planted sequentially along the long side of the shell 1 in the solid flow layer 16 (with the upper ends of the plants in the plant strips 17 penetrating the overflow layer 9), play a core ecological role in preventing clogging and filtration. Their root systems form a three-dimensional network, which can physically intercept small suspended particulate impurities in the wastewater and secrete antibacterial substances to inhibit excessive microbial growth and prevent biofilm adhesion from clogging the substrate pores. Based on the stable flow and infiltration design of the solid flow layer 16, part of the wastewater infiltrates vertically while another part flows slowly laterally. This ensures sufficient contact between the wastewater and the plant roots and substrate, improving the filtration and purification effect, while effectively preventing excessively fast water flow from eroding the substrate or causing stagnation and sedimentation, further reducing the risk of clogging. After being treated layer by layer in the solid flow layer 16, most impurities in the wastewater are intercepted, and the water is initially purified. It then slowly infiltrates to the bottom guide layer 20, entering the subsequent water collection and diversion stage.
[0044] After the wastewater enters the diversion layer 20, the diversion layer 20 completely eliminates bottom blockage through water collection and diversion and closed-loop sludge discharge, ultimately achieving compliant discharge. During this process, the gravel filling the diversion layer 20 completely encloses the distribution pipe 7 and the return pipe 8. The gravel particle size is precisely matched to the pipe design, providing a clear flow channel for the infiltrated wastewater while preventing the gravel from clogging the pipes. At the same time, it carries away small particulate impurities remaining beside the pipes. The wastewater diffuses along the gaps between the gravel and evenly enters the return pipes 8 (branch of distribution pipe 7) on both sides of the distribution pipe 7, and then converges into the inclined distribution pipe 7 (main distribution pipe 7). Since the lower end of the distribution pipe 7 faces the sedimentation hopper 4, under the action of gravity and the slight negative pressure formed by the sedimentation hopper 4, the water carrying the remaining small particulate impurities flows back to the sedimentation hopper 4 along the distribution pipe 7, completing the closed-loop collection of impurities and completely preventing the accumulation of impurities at the bottom.
[0045] During wastewater treatment, the sedimentation tank 4 continuously collects various impurities and periodically discharges sludge through its bottom sludge discharge structure, maintaining a low internal liquid level and creating a slight negative pressure. This negative pressure continuously attracts the end of the distribution pipe 7, pulling the water carrying impurities back into the pipe. Together, these factors ensure that small particles of impurities and sludge do not accumulate in the guide layer 20 or the pipes, but instead flow back to the sedimentation tank 4 for collection. Simultaneously, the gaps between the gravel in the guide layer 20 provide a clear channel for impurity movement. Combined with the comprehensive layout of the return pipe 8 and the distribution pipe 7, there are no dead zones where impurities accumulate, further ensuring smooth backflow.
[0046] Finally, the qualified water, after undergoing three layers of filtration and full-process anti-clogging treatment, is discharged through the outlet 23 at the other end of the shell 1. The entire process achieves synergistic promotion of water flow filtration and anti-clogging, effectively solving the pain point of easy siltation and clogging in subsurface flow constructed wetlands, while improving wastewater purification efficiency and ensuring stable, long-term, and efficient operation of the equipment.
[0047] In order to regularly clean the sludge in sedimentation hopper 4, the following features are specifically designed:
[0048] like Figure 1 As shown, two sludge pumps 6 are installed at one end of the shell 1 near the water inlet channel 2, and the input ends of the two sludge pumps 6 are respectively connected to the lower part of the sedimentation hopper 4.
[0049] During the long-term operation of sedimentation hopper 4, sludge will continue to accumulate at the bottom of the hopper. The simultaneous operation of two sludge pumps 6 can achieve rapid and thorough cleaning of sludge, preventing sludge from accumulating too high and overflowing into the overflow layer 9 or return water pipe 8, further enhancing the anti-clogging effect of the pretreatment stage. There is no need to frequently excavate sedimentation hopper 4, reducing the difficulty of operation and maintenance, which is in line with the design goal of long-term operation of the equipment. It works in synergy with the sludge collection function of sedimentation hopper 4 to ensure the integrity of the closed-loop sludge discharge system.
[0050] In order to buffer the sewage flowing into the sedimentation hopper 4 and prevent the sewage from being directly injected into the solid flow layer 16, the following features are specifically provided:
[0051] like Figure 2 and Figure 3 As shown, a diversion plate 3 is installed at the lower end of the inlet channel 2. The upper part of the diversion plate 3 is inclined, and the upper part of the diversion plate 3 covers the connection between the sedimentation tank 4 and the solid flow layer 16, preventing sewage injected from the upper end of the sedimentation tank 4 from flowing directly into the solid flow layer 16. When sewage enters the sedimentation tank 4 from the inlet channel 2, the inclined diversion plate 3 can buffer the impact force of the water flow, preventing the water flow from directly hitting the connection and the surface substrate of the solid flow layer 16, preventing substrate loss and loosening of plant roots. At the same time, it forces the sewage to stay in the sedimentation tank 4 for a sufficient amount of time and settle steadily, ensuring that most of the sludge and large particles are deposited at the bottom of the tank, preventing untreated sewage from short-circuiting into the solid flow layer 16, and reducing the risk of blockage in the solid flow layer 16 from the source.
[0052] To prevent wastewater in sedimentation tank 4 from flowing back into return water pipe 8, the following features are specifically designed:
[0053] like Figure 4 As shown, a flow stop cover 5 is provided on the side of the sedimentation tank 4 away from the water distribution pipe 7. The flow stop cover 5 is coaxial with the return water pipe 8.
[0054] The upper end of the flow-stopping cover 5 is hinged to the sedimentation hopper 4 via a torsion spring. When impacted by water flow, the flow-stopping cover 5 deflects away from the distribution pipe 7. During normal operation, the flow-stopping cover 5 adheres to the end of the return pipe 8 under the force of the torsion spring, forming a seal to prevent the sludge or unsettled wastewater accumulated in the sedimentation hopper 4 from flowing back to the distribution pipe 7 and the return pipe 8, avoiding blockage of the perforations in the return pipe 8, and ensuring the normal functioning of the diversion and impurity return of the return pipe 8. When water carrying impurities flows from the distribution pipe 7 to the sedimentation hopper 4, the impact force of the water flow can push the flow-stopping cover 5 to deflect, without affecting the normal return of impurities, achieving a two-way adaptation between backflow prevention and normal sludge discharge.
[0055] To prevent excessive evaporation of water in constructed wetlands during the dry season, and also to prevent external contaminants from polluting the constructed wetlands, the following features are specifically designed:
[0056] like Figure 1 As shown, a perforated plate 10 is provided on the side of the water inlet channel 2. The perforated plate 10 is fixedly connected to the inner wall of the shell 1. The perforated plate 10 has through holes along its long side for the plants of the three plant belts 17 to pass through.
[0057] During equipment operation, the perforated plate 10 covers the upper part of the shell 1, which can effectively reduce the excessive evaporation of water inside the equipment during the dry season, prevent the substrate of the solid flow layer 16 from hardening due to lack of water, and ensure the smooth flow of water infiltration channels. At the same time, the perforated plate 10 can block external debris such as fallen leaves and other impurities from entering the equipment, preventing impurities from clogging the pores of the overflow layer 9, the substrate of the solid flow layer 16, or the perforations of the return water pipe 8, further strengthening the anti-clogging protection of the equipment. The setting of the through holes can ensure the normal growth of the plant strip 17 without affecting its ecological anti-clogging and purification functions.
[0058] In order to shield the overflow hole 14 during daily use and release water flow when there is excessive water at the upper end of the perforated plate 10, the following features are also provided:
[0059] like Figure 6 and Figure 7 As shown, an overflow plate 13 is slidably disposed on the side of the overflow hole 14 near the perforated plate 10;
[0060] A plastic hollow pipe 15 is fixedly connected to the middle of the overflow plate 13. The water overflowing to the upper end of the perforated plate 10 pushes the plastic hollow pipe 15 to move upward.
[0061] Under normal, non-rainy season operating conditions, the overflow plate 13 is in a closed state, blocking the overflow hole 14 to prevent external impurities from entering the equipment through the overflow hole 14, thus avoiding blockage of the overflow layer 9, the solidification layer 16, or the guide layer 20, and reducing water evaporation inside the equipment. When the water level rises during the rainy season, the overflow plate 13 can slide open according to the water level change, working with the overflow hole 14 to quickly discharge excess water, realizing the on-demand opening and closing of the overflow hole 14, taking into account both daily protection and rainy season drainage, and strengthening the equipment's water level adaptive anti-clogging capability.
[0062] When excessive water accumulates at the top of the perforated plate 10, the gravity of the accumulated water pushes the plastic hollow pipe 15 upward, which in turn drives the overflow plate 13 to move upward simultaneously, automatically opening the overflow hole 14 to release the accumulated water. This allows for adaptive water level adjustment without manual operation, preventing excessive water accumulation at the top of the perforated plate 10 from flowing back into the inlet channel 2 or seeping into the solid flow layer 16, which could lead to anaerobic substrate water accumulation. This also prevents excessive growth of the microbial film that could cause blockage and ensures the stability of equipment operation.
[0063] To facilitate the flow of excess water from the lower end of the perforated plate 10 to its surface, allowing the overflow hole 14 to release the excess water, the following features are specifically provided:
[0064] like Figure 2 and Figure 5 As shown, an overflow plate 11 is provided at the upper end of the perforated plate 10 near the water inlet channel 2. The overflow plate 11 is provided with guide pins 12 arranged at equal angles along the circumference, and the guide pins 12 are fixedly connected to the perforated plate 10.
[0065] A spring is coaxially sleeved on the guide pin 12. The upper end of the spring is fixedly connected to the upper end of the guide pin 12, and the lower end is fixedly connected to the upper end of the overflow plate 11.
[0066] During equipment operation, if excess water cannot seep down from the lower end of the perforated plate 10, the water will converge into the overflow plate 11. When the weight of the water reaches a certain level, it will compress the spring from bottom to top, causing the overflow plate 11 to move upward along the guide pin 12, creating a gap between the overflow plate 11 and the perforated plate 10. This allows excess water at the lower end of the perforated plate 10 to flow through this gap to the surface of the perforated plate 10. Subsequently, the water pushes the plastic hollow pipe 15 to open the overflow plate 13, allowing the water to be discharged smoothly through the overflow hole 14. This prevents excess water from accumulating at the lower end of the perforated plate 10, further enhancing the water level regulation and anti-clogging effect. The guide pin 12 ensures that the overflow plate 11 moves smoothly up and down, preventing deviation and jamming that could affect water flow.
[0067] To prevent the roots of the plants in the plant strip 17 from rotting, and also to facilitate the modular assembly and disassembly of the three types of plant strips 17, the following features are specifically designed:
[0068] like Figure 6 As shown, three planting pots 18 are arranged in an array along the long side of the lower end of the perforated plate 10, and connecting holes 19 are evenly spaced at the lower end of the planting pots 18. During the planting of the plant strips 17, the three planting pots 18 correspond to the three plant strips 17 respectively, which can realize modular planting and disassembly of plants, facilitate the replacement and maintenance of plants later, and reduce the difficulty of operation and maintenance. The connecting holes 19 at the lower end of the planting pots 18 can allow water to seep smoothly downward, avoid water accumulation and rotting at the plant roots, ensure the normal growth of plant roots, give full play to their three-dimensional interception and antibacterial and anti-clogging functions, and at the same time, the connecting holes 19 can intercept some large particles of impurities, further reducing the impurity load entering the guide layer 20.
[0069] To further filter the water flowing into the guide layer 20, the following features are specifically designed:
[0070] like Figure 6 and Figure 8As shown, a keel plate 22 is provided at the lower end of the planting pot 18, which is fixedly connected to the shell 1. An impermeable membrane 21 is provided at the upper end of the keel plate 22, which abuts against the lower end of the planting pot 18. During the process of water infiltrating from the solid flow layer 16 to the guide flow layer 20, the impermeable membrane 21 can guide the water flow to infiltrate in an orderly manner only through the connecting hole 19 at the lower end of the planting pot 18, prolonging the residence time of the water flow in the solid flow layer 16, allowing the plant roots and substrate to fully exert their filtering effect, and further intercepting fine impurities. The keel plate 22 can provide stable support for the planting pot 18 and the impermeable membrane 21, preventing the water flow from short-circuiting due to damage to the impermeable membrane 21, and at the same time preventing the substrate in the solid flow layer 16 from sliding directly to the guide flow layer 20, preventing the gaps between the gravel in the guide flow layer 20 from being blocked, and strengthening the synergistic effect of filtration and anti-blocking.
[0071] To prevent some impurities from flowing directly out of the shell 1 via the water flow, the following features are specifically provided:
[0072] like Figure 8 As shown, a filter screen 24 is installed on the side of the water outlet 23 near the planting pot 18. The filter screen 24 intercepts impurities in the water. Before the qualified water is discharged from the equipment, the filter screen 24 can perform a final interception of small impurities in the water that have not been completely collected, preventing impurities from being discharged with the water and causing secondary pollution. At the same time, it avoids small impurities from clogging the water outlet 23, ensuring smooth water discharge. The setting of the filter screen 24 works synergistically with the filtration and anti-clogging functions of the sedimentation tank 4, the solid flow layer 16, and the flow guiding layer 20 to build a full-process impurity interception system, further improving the purification effect and anti-clogging stability of the equipment.
[0073] The detailed working principle of this equipment is as follows: The wastewater to be treated first enters the equipment through the inlet channel 2 at one end of the shell 1. The sedimentation hopper 4 at the lower end of the inlet channel 2 immediately exerts gravity sedimentation to initially collect sludge and large particulate impurities in the wastewater, preventing easily accumulating substances from entering the subsequent stratified structure from the source, thus building a solid first line of defense against clogging. At the same time, the overflow layer 9 at the top of the shell 1 simultaneously intercepts floating debris on the surface of the wastewater, preventing it from clogging the pores of the lower layers. When the water level is too high during the rainy season, the overflow holes 14 on both sides of the shell 1 quickly open to drain water, preventing water accumulation in the bed from causing excessive growth of microbial film and sludge accumulation, thus ensuring stable operation.
[0074] The pretreated wastewater enters the overflow layer 9 evenly through the connection between the sedimentation tank 4 and the overflow layer 9, and then permeates from top to bottom into the middle solid flow layer 16. Three plant strips 17 are planted sequentially along the long side of the shell 1 within the solid flow layer 16. The upper ends of the plants in the plant strips 17 penetrate the overflow layer 9, and their roots form a three-dimensional network within the solid flow layer 16. This network not only physically intercepts small suspended particulate impurities in the wastewater but also secretes antibacterial substances to inhibit excessive microbial growth, preventing biofilm from clogging the substrate pores. Utilizing the stable flow and permeability characteristics of the solid flow layer 16, part of the wastewater permeates vertically downwards, while another part slowly permeates laterally towards the outlet, ensuring full contact between the wastewater and the plant roots and substrate. This improves the purification effect and prevents water flow from eroding the substrate or causing stagnation and sedimentation, further reducing the risk of clogging.
[0075] After being purified by the solid flow layer 16, the wastewater slowly seeps down to the lowest guide layer 20. The gravel filling the guide layer 20 completely encloses the distribution pipe 7 and the return pipes 8 on both sides. The gravel and the pipes are precisely matched, providing a clear water flow channel while preventing the gravel from clogging the perforations of the return pipes 8. The wastewater diffuses along the gaps between the gravel and enters the return pipes 8 through the perforations, then converges into the inclined distribution pipe 7. Since the lower end of the distribution pipe 7 faces the sedimentation tank 4, under the combined action of gravity and the slight negative pressure formed by the sedimentation tank 4, the water carrying the remaining fine impurities flows back to the sedimentation tank 4 along the distribution pipe 7, completing the closed-loop collection of impurities and completely preventing bottom sedimentation.
[0076] During equipment operation, the perforated plate 10 reduces water evaporation and blocks external impurities. If excess water cannot seep down in time at its lower end, it will converge at the lower end of the overflow plate 11 near the inlet channel 2 at the upper end of the perforated plate 10. When the short-term water flow is too large, causing the water flow to accumulate to a certain level, the water flow will push the overflow plate 11 upward along the guide pin 12, allowing the water flow to flow through the gap between the overflow plate 11 and the perforated plate 10 to the surface of the perforated plate 10. Subsequently, the gravity of the accumulated water pushes the plastic hollow pipe 15 on the overflow plate 13 upward, causing the overflow plate 13 to slide open, and the excess water flow will be discharged through the overflow holes 14 on both sides of the shell 1, realizing adaptive water level adjustment and avoiding backflow or blockage caused by siltation. Throughout the process, the sedimentation tank 4 continuously collects various impurities to ensure that there is no excessive accumulation of impurities in the subsequent layered structure. The gravel in the guide layer 20, together with the water distribution pipe 7 and the return water pipe 8, achieve full-area water collection and directional flow, with no dead corners where impurities are trapped. Finally, the qualified water, after being filtered through three layers and treated with anti-clogging measures throughout the process, is smoothly discharged through the outlet 23 at the other end of the shell 1. This achieves the synergistic promotion of water flow filtration and anti-clogging, effectively solving the problem of frequent clogging in existing subsurface flow constructed wetlands and ensuring the stable, long-term, and efficient operation of the equipment.
[0077] The above embodiments only illustrate one or more implementations of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.
Claims
1. A clog-resistant subsurface flow constructed wetland device, characterized in that, include: The shell (1) has an inlet channel (2) at one end and an outlet (23) at the other end. The middle of the shell (1) is provided with an overflow layer (9) for intercepting debris and draining water, a solid flow layer (16) for stabilizing flow and infiltration, and a flow guiding layer (20) for collecting and guiding water in sequence from top to bottom. Overflow holes (14) are provided at equal intervals on both sides of the shell (1). The solid flow layer (16) is planted with three plant strips (17) with their upper ends passing through the overflow layer (9) in sequence along the long side. A sedimentation hopper (4) is installed at the lower end of the inlet channel (2). The middle part of the sedimentation hopper (4) is connected to the overflow layer (9). The lower part of the sedimentation hopper (4) is connected to a water distribution pipe (7) that is inclined and penetrates the guide layer (20). The two sides of the water distribution pipe (7) are connected to perforated return water pipes (8) at equal intervals. The guide layer (20) is filled with gravel that wraps the water distribution pipe (7) and the return water pipe (8). After the water passes through the overflow layer (9), the solid flow layer (16) and the guide layer (20) from top to bottom, the impurities in the water flow back to the sedimentation tank (4) through the return water pipe (8) and the water distribution pipe (7).
2. The anti-clogging subsurface flow constructed wetland device according to claim 1, characterized in that, Two sludge pumps (6) are installed at one end of the shell (1) near the water inlet channel (2), and the input ends of the two sludge pumps (6) are respectively connected to the lower part of the sedimentation hopper (4).
3. The anti-clogging subsurface flow constructed wetland device according to claim 1, characterized in that, A diversion plate (3) is installed at the lower end of the inlet channel (2). The upper part of the diversion plate (3) is inclined. The upper part of the diversion plate (3) covers the connection between the sedimentation tank (4) and the solid flow layer (16) to prevent the sewage injected through the upper end of the sedimentation tank (4) from flowing directly into the solid flow layer (16).
4. The anti-clogging subsurface flow constructed wetland device according to claim 3, characterized in that, A flow stop cover (5) is provided on the side of the sedimentation tank (4) away from the water distribution pipe (7), and the flow stop cover (5) is coaxial with the return water pipe (8); The upper end of the stop cover (5) is hinged to the sedimentation hopper (4) by a torsion spring. When the stop cover (5) is impacted by the water flow, it deflects to the side away from the water distribution pipe (7).
5. The anti-clogging subsurface flow constructed wetland device according to claim 3, characterized in that, A perforated plate (10) is provided on the side of the water inlet channel (2). The perforated plate (10) is fixed to the inner wall of the shell (1). The perforated plate (10) has through holes along its long side for the plants of the three plant belts (17) to pass through.
6. The anti-clogging subsurface flow constructed wetland device according to claim 5, characterized in that, An overflow plate (13) is slidably provided on the side of the overflow hole (14) near the perforated plate (10); A plastic hollow pipe (15) is fixed in the middle of the overflow plate (13). The water overflowing to the upper end of the perforated plate (10) pushes the plastic hollow pipe (15) upward.
7. The anti-clogging subsurface flow constructed wetland device according to claim 6, characterized in that, An overflow plate (11) is provided at the upper end of the perforated plate (10) near the water inlet channel (2). The overflow plate (11) is provided with guide pins (12) arranged at equal angles along the circumference. The guide pins (12) are fixedly connected to the perforated plate (10). A spring is coaxially sleeved on the guide pin (12). The upper end of the spring is fixedly connected to the upper end of the guide pin (12), and the lower end is fixedly connected to the upper end of the overflow plate (11).
8. The anti-clogging subsurface flow constructed wetland device according to claim 7, characterized in that, Three planting pots (18) are arranged in an array along the long side of the lower end of the perforated board (10), and the lower end of the planting pots (18) is provided with connecting holes (19) arranged at equal intervals.
9. A clog-resistant subsurface flow constructed wetland device according to claim 8, characterized in that, The lower end of the planting pot (18) is provided with a keel plate (22), which is fixedly connected to the shell (1). The upper end of the keel plate (22) is provided with a waterproof membrane (21), which abuts against the lower end of the planting pot (18).
10. A clog-resistant subsurface flow constructed wetland device according to claim 1, characterized in that, A filter screen (24) is installed on the side of the water outlet (23) near the planting pot (18) to intercept impurities in the water.