Modularized combined constructed wetland system
By using modular design and electric gates, the problem of sewage inflow caused by wetland module failure in the subsurface flow constructed wetland system was solved, achieving stable system operation and efficient sewage treatment, and reducing maintenance costs and blockage risks.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-12
- Publication Date
- 2026-04-07
AI Technical Summary
In existing subsurface flow constructed wetland treatment systems, when a wetland module malfunctions, wastewater still flows into the malfunctioning module, affecting treatment efficiency and water quality, and potentially causing environmental pollution.
The modular design incorporates perforated walls and electric gates on both sides of each wetland module. Combined with intelligent monitoring and high-precision gate valves, it enables flexible control of the sewage flow path and automatic isolation of faulty modules.
It improves the stability and reliability of the system, reduces maintenance costs, extends the clogging cycle of the wetland module, and enhances processing efficiency and system adaptability.
Smart Images
Figure CN224091717U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of wastewater treatment technology, specifically to a modular combined constructed wetland system. Background Technology
[0002] In the fields of environmental protection and water resource treatment, constructed wetland treatment systems have been widely used as an eco-friendly and cost-effective wastewater treatment technology. Traditional constructed wetland treatment systems are mainly divided into two categories based on the flow characteristics of wastewater within the wetland: surface flow constructed wetland treatment systems and subsurface flow constructed wetland treatment systems.
[0003] Surface flow constructed wetland systems treat wastewater by creating a shallow, horizontal flow layer (typically 0.1 to 0.6 meters above the surface) at a slow velocity. This system relies on the combined physical, chemical, and biological interactions between wetland plants, substrate, and internal microorganisms to purify the wastewater. While surface flow constructed wetland systems offer advantages such as simple design, low investment, and low operating costs, their low hydraulic load results in a large footprint, a significant limiting factor in situations with limited land resources. To overcome this drawback, subsurface flow constructed wetland systems have emerged. Subsurface flow systems involve wastewater flowing beneath the surface of the wetland bed, with the water level below the wetland packing material layer. Wastewater flows slowly across the packing bed, where pollutants are effectively removed through the biofilm growing on the packing surface, the abundant plant roots, and the packing material's interception effect. Subsurface flow constructed wetland systems not only fully utilize the treatment capacity of the packing material and plant roots, improving treatment efficiency, but also require a relatively smaller footprint compared to surface flow systems, making them more suitable for environments with limited land resources.
[0004] Current subsurface flow constructed wetland treatment systems typically consist of several independent wetland modules, each independently handling a portion of the wastewater treatment. However, while this modular design offers flexibility and scalability, it also exposes a potential problem: when a wetland module malfunctions (such as due to filler blockage, plant death, or system leakage), wastewater will still flow into the malfunctioning module along its original flow path. This not only affects the overall treatment efficiency of the system but may also lead to untreated wastewater being discharged directly, causing environmental pollution. Utility Model Content
[0005] This application aims to address the problems existing in current subsurface flow constructed wetland treatment systems, namely, how to prevent sewage from continuing to flow into a faulty wetland module when it malfunctions, thereby ensuring the stable operation of the entire treatment system and that the effluent quality meets standards, and improving the reliability and environmental adaptability of the subsurface flow constructed wetland treatment system.
[0006] A modular constructed wetland system includes: a main inlet and outlet water distribution channel, and at least two wetland modules; each wetland module is surrounded by a longitudinal branch water distribution channel and a transverse branch water distribution channel, with each pair of wetland modules sharing one of the longitudinal branch water distribution channels; the main inlet and outlet water distribution channel is connected to the longitudinal and transverse branch water distribution channels of the first wetland module; the main outlet water distribution channel is connected to the longitudinal and transverse branch water distribution channels of the last wetland module.
[0007] Each wetland module has perforated walls on the left and right sides and solid walls on the top and bottom sides. The left and right sides of the walls are equipped with electric gates that can prevent sewage from flowing into the corresponding wetland module.
[0008] A gate valve is installed at the left end of the transverse branch irrigation canal corresponding to each wetland module.
[0009] Furthermore, in the modular constructed wetland system described above, the aperture of the holes in the perforated wall decreases in a gradient from top to bottom.
[0010] Furthermore, in the modular constructed wetland system described above, the holes on the perforated wall are divided into three types according to their diameter: 10mm diameter through holes, 6mm diameter through holes, and 3mm diameter through holes; wherein, the 10mm diameter through holes are distributed in the upper region of the perforated wall; the 6mm diameter through holes are distributed in the middle region of the perforated wall; and the 3mm diameter through holes are distributed in the lower region of the perforated wall.
[0011] Furthermore, in the modular constructed wetland system described above, each wetland module is equipped with a monitoring probe for measuring the concentration of suspended solids in the water.
[0012] Furthermore, in the modular constructed wetland system described above, the gate valve is a bidirectional gate valve.
[0013] Furthermore, in the modular constructed wetland system described above, the wetland modules are rectangular, pentagonal, or hexagonal in shape.
[0014] Furthermore, in the modular constructed wetland system described above, the filler material within the wetland module is arranged sequentially from bottom to top as a first crushed stone layer, a filter media layer, a second crushed stone layer, and a pebble layer.
[0015] Furthermore, in the modular constructed wetland system described above, the particle size of the first crushed stone layer is 30-50 mm; the particle size of the filter media layer is 20-30 mm; the particle size of the second crushed stone layer is 5-10 mm; and the particle size of the pebble layer is 10-20 mm.
[0016] Furthermore, in the modular constructed wetland system described above, the thickness of the first gravel layer is 500 mm; the thickness of the filter media layer is 400 mm; the thickness of the second gravel layer is 300 mm; and the thickness of the pebble layer is 100 mm.
[0017] The modular constructed wetland system provided by this utility model uses perforated walls on the left and right sides and solid walls on the top and bottom sides of each wetland module. Electric gates are installed on the sides of the left and right walls, which enables the system to flexibly control the flow path of sewage, improves the system's response speed to faults, and enhances the system's stability and reliability. Attached Figure Description
[0018] Figure 1 This is a top view of the modular combined artificial wetland system provided by this utility model;
[0019] Figure 2 This is a schematic diagram illustrating the overall normal operating status of the constructed wetland system.
[0020] Figure 3 This is a schematic diagram of the operating status of a wetland module in an artificial wetland system when it malfunctions.
[0021] Figure 4 This is a schematic cross-sectional view of the wetland module provided in this application;
[0022] Figure label:
[0023] 1-Main inlet and outlet water distribution channel; 2-Longitudinal branch water distribution channel; 3-Wetland module; 4-Electric gate; 5-Gate valve; 6-Monitoring probe; 7-Main outlet water distribution channel; 8-Transverse branch water distribution channel;
[0024] 31-Upper solid wall; 32-Lower solid wall; 33-Left perforated wall; 34-Right perforated wall; 35-First crushed stone layer; 36-Filter material layer; 37-Second crushed stone layer; 38-Pebble layer. Detailed Implementation
[0025] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.
[0026] Figure 1 A schematic diagram of the modular constructed wetland system provided in this application is shown below. Figure 1As shown, it includes: a main inlet and outlet water distribution channel 1, a main outlet water distribution channel 7, and at least two wetland modules 3; each wetland module 3 is provided with a longitudinal branch water distribution channel 2 and a transverse branch water distribution channel 8 around its perimeter, and each pair of wetland modules 3 shares one of the longitudinal branch water distribution channels 2; the main inlet and outlet water distribution channel 1 is connected to the longitudinal branch water distribution channel 2 and the transverse branch water distribution channel 8 of the first wetland module 3; the main outlet water distribution channel 7 is connected to the longitudinal branch water distribution channel 2 and the transverse branch water distribution channel 8 of the last wetland module 3; the left and right side walls of each wetland module 3 are constructed of perforated walls, and the top and bottom sides are constructed of solid walls, and the sides of the left and right side walls are respectively provided with electric gates 4 that can prevent sewage from flowing into the corresponding wetland module; a gate valve 5 is respectively provided at the left end of the transverse branch water distribution channel 8 corresponding to each wetland module 3.
[0027] Specifically, Figure 2 This is a schematic diagram of the overall normal operating status of the constructed wetland system, such as... Figure 2 As shown, when all wetland modules in the constructed wetland system are fault-free and operating normally, all gate valves 5 are closed to prevent sewage from flowing directly from the transverse distribution channel 8 into the next level wetland module. At the same time, the electric gate 4 corresponding to the first wetland module is opened. At this time, sewage enters from the main inlet channel 1 and first flows into the longitudinal distribution channel 2 of the first wetland module 3. It seeps into the first wetland module through the longitudinal distribution channel 2. Then, the sewage is treated by the packing material and plants inside the first wetland module. The treated sewage enters the second wetland module. At this time, the electric gate 4 corresponding to the second wetland module is opened to allow the sewage treated by the previous wetland module to enter the wetland module for further treatment. This process continues until the sewage treated by the last wetland module flows out from the main outlet channel 7. Figure 3 This is a schematic diagram illustrating the operational status of a specific wetland module in an constructed wetland system when it malfunctions. Figure 3 As shown, assuming the second wetland module malfunctions, the electric gates 4 on both sides of the second wetland module are closed. Simultaneously, the gate valves 5 on the upper and lower distribution channels on the left side of the second wetland module are opened, allowing the wastewater treated by the first-stage wetland module to bypass the malfunctioning wetland module and flow into the third normal wetland module through the corresponding transverse distribution channel 8 of the second wetland module for continued wastewater treatment. To achieve this bypassing of the malfunctioning wetland module by the wastewater treated by the previous wetland module, this application employs the following solution: the left and right walls of the wetland module 3 are constructed using perforated walls, while the upper and lower walls are constructed using solid walls. Electric gates 4 are installed on the sides of the left and right walls to prevent wastewater from flowing into the corresponding wetland module. Before the wastewater treated by the previous wetland module flows into the malfunctioning wetland module, the electric gates 4 on both sides of the malfunctioning wetland module are closed, thereby preventing wastewater from flowing into the malfunctioning wetland module.
[0028] This application utilizes electrically operated gates on both sides of each wetland module, enabling the system to flexibly control the flow path of wastewater. When a wetland module malfunctions, its electrically operated gate can be quickly closed, preventing wastewater from flowing in and thus avoiding the direct discharge of untreated or insufficiently treated wastewater from the faulty module. This design allows for a faster and more effective response to faults, improving the stability and reliability of the entire treatment system. Furthermore, the modular design facilitates the maintenance and management of the wetland modules. When a module malfunctions, it can be repaired or replaced individually without affecting the normal operation of other modules, thereby improving the system's intelligent operation and maintenance efficiency; and reducing single-repair costs by more than 70%, thus lowering maintenance costs. In addition, the electrically operated gates allow for more precise and convenient control of wastewater flow, reducing the complexity and cost of maintenance and management.
[0029] The modular constructed wetland system provided in this application effectively solves the problems caused by wetland module failures in subsurface flow constructed wetland treatment systems through innovative modular design and the application of electric gates, improving the system's flexibility, controllability, treatment efficiency, maintenance and management convenience, as well as scalability and adaptability.
[0030] Furthermore, the diameter of the holes in the perforated wall decreases in a gradient from top to bottom.
[0031] Specifically, this application effectively avoids the deposition of suspended solids by setting the pore size of the perforated wall to decrease gradually from top to bottom. Compared with traditional perforated walls with uniform pore size, the stepped perforated wall design can disperse the impact force of water flow, reduce local blockage, and significantly improve the anti-clogging ability of the system, thus extending the clogging cycle of the wetland module's packing material by 3 times.
[0032] This application embodiment exemplarily provides a distribution state of aperture, specifically: the holes on the perforated wall are divided into three types according to aperture: 10mm aperture through holes, 6mm aperture through holes, and 3mm aperture through holes; wherein, the 10mm aperture through holes are distributed in the upper region of the perforated wall; the 6mm aperture through holes are distributed in the middle region of the perforated wall; and the 3mm aperture through holes are distributed in the lower region of the perforated wall.
[0033] Furthermore, each of the wetland modules 3 is equipped with a monitoring probe 6 for measuring the concentration of suspended solids in the water.
[0034] Specifically, this application embeds online monitoring probes in each wetland module. The detected suspended solids concentration data is uploaded to the PLC at regular intervals (e.g., every 15 minutes) to provide real-time feedback on the operating status of each module. When the suspended solids removal rate decreases by 20%, it indicates that the wetland module is in a fault state, triggering an early warning. The system automatically opens the electric gate 4 of the corresponding wetland module, dynamically switching the sewage to the fault path, allowing the sewage to bypass the faulty wetland module.
[0035] Furthermore, the gate valve 5 is a bidirectional gate valve.
[0036] Specifically, the gate valve 5 of this application adopts a bidirectional high-precision gate valve, which can support forward and reverse water conveyance, and the gate valve has a remote control function, which can adjust the flow rate of sewage in real time.
[0037] The system provided in this application adopts a combination of high-precision gate valves and multi-stage perforated walls to achieve a dual improvement in water distribution uniformity and anti-clogging capability; combined with intelligent monitoring and gate valve linkage, it realizes automatic isolation of faulty wetland modules and dynamic switching of sewage paths; and supports seamless switching between series, parallel and mixed modes, thereby adapting to different water quality and load requirements.
[0038] Furthermore, the wetland module 3 can be a rectangular, pentagonal, or hexagonal structure. This application does not impose any restrictions on this, as long as it ensures that sewage cannot flow into a wetland module when it malfunctions.
[0039] Furthermore, Figure 4 This is a schematic cross-sectional view of the wetland module provided in this application, such as... Figure 4 As shown, the filler material in the wetland module 3 is arranged in the following order from bottom to top: a first crushed stone layer 35, a filter material layer 36, a second crushed stone layer 37, and a pebble layer 38.
[0040] Specifically, a pebble layer is placed on the surface to prevent erosion, protect the underlying structure, prevent damage from plant roots, and facilitate even water inflow. A second layer of crushed stone provides support and prevents clogging, while also promoting water flow distribution. It traps suspended solids in the water and serves as a carrier for microorganisms. The filter media layer consists of calcium-based denitrification and phosphorus removal media (commercially available), primarily composed of calcium carbonate, calcium oxide, and biomass (oyster shells, seashells, and eggshells, etc.). This media is strongly alkaline, raising the pH of the water, slowly releasing calcium ions, and promoting the chemical precipitation of phosphorus. Its porous structure provides a habitat for nitrifying / denitrifying bacteria, promoting the conversion of ammonia nitrogen to nitrogen gas. The slightly alkaline environment optimizes the activity of denitrifying bacteria, accelerating the denitrification process. In addition to providing a better growth environment for microorganisms, the calcium-based denitrification and phosphorus removal media significantly improves the denitrification and phosphorus removal efficiency of constructed wetlands, increases water activity, and thus improves the aquatic ecosystem. Furthermore, this filter media has a relatively high porosity, is not easily clogged, and has a long service life. The first gravel layer is located at the bottom of the wetland and serves to support and guide water.
[0041] This application improves wastewater treatment efficiency by arranging the packing material in the wetland module in the order of bottom to top: a first crushed stone layer, a filter media layer, a second crushed stone layer, and a pebble layer. This creates a physicochemical-biological coupling system between the calcium-based substrate and the double-layered crushed stone. The calcium-based material fixes phosphorus through chemical precipitation and provides an alkaline microenvironment to promote the activity of nitrifying bacteria. Combined with the denitrification zone, it achieves nitrogen removal throughout the entire process.
[0042] Further, the particle size of the first crushed stone layer 35 is 30-50 mm; the particle size of the filter media layer 36 is 20-30 mm; the particle size of the second crushed stone layer 37 is 5-10 mm; and the particle size of the pebble layer 38 is 10-20 mm. The thickness of the first crushed stone layer 35 is 500 mm; the thickness of the filter media layer 36 is 400 mm; the thickness of the second crushed stone layer 37 is 300 mm; and the thickness of the pebble layer 38 is 100 mm.
[0043] In this study, the dissolved oxygen concentration (DO) in the surface pebble zone is >4 mg / L (aerobic nitrification), the dissolved oxygen concentration (DO) in the middle calcium substrate is in the range of 0.5-2 mg / L (facultative denitrification), and the dissolved oxygen concentration (DO) in the bottom gravel layer is <0.5 mg / L (anaerobic phosphorus release). Therefore, this application uses a particle size gradient configuration to form a structure with increasing porosity, combined with the anti-caking properties of calcium-based materials, to extend the system's operating cycle to 5-8 years, which is 60% longer than that of conventional wetlands.
[0044] Example:
[0045] The collected rural domestic sewage (excluding toilet flushing water) is first filtered through a screen, then treated in a sedimentation tank. The treated effluent then enters a horizontal subsurface flow constructed wetland for further treatment, with a treatment capacity of 50m³. 3 / d. Divided into 6 rectangular modules (3m×4m), with a total residence time of 24 hours; the perforated wall aperture is 10mm for the upper layer, 6mm for the middle layer, and 3mm for the lower layer, improving the water distribution uniformity coefficient from the traditional 0.7 to 0.92. Experiments show that through a dual mechanism of "structural anti-clogging + dynamic control," the clogging cycle of constructed wetlands is extended from the traditional 6-12 months to 3-5 years, reducing operation and maintenance costs by approximately 60%.
[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.
Claims
1. A modular combined constructed wetland system, characterized in that, include: The wetland consists of a main inlet water distribution channel (1), a main outlet water distribution channel (7), and at least two wetland modules (3); each wetland module (3) is surrounded by a longitudinal branch water distribution channel (2) and a transverse branch water distribution channel (8), and two wetland modules (3) share one of the longitudinal branch water distribution channels (2); the main inlet water distribution channel (1) is connected to the longitudinal branch water distribution channel (2) and the transverse branch water distribution channel (8) of the first wetland module (3); the main outlet water distribution channel (7) is connected to the longitudinal branch water distribution channel (2) and the transverse branch water distribution channel (8) of the last wetland module (3); The left and right walls of each wetland module (3) are made of perforated walls, and the top and bottom walls are made of solid walls. The left and right walls are respectively equipped with electric gates (4) that can prevent sewage from flowing into the corresponding wetland module. Gate valves (5) are respectively installed at the left end of the transverse branch irrigation canal (8) corresponding to each wetland module (3).
2. The modular combined constructed wetland system according to claim 1, characterized in that, The diameter of the holes in the perforated wall decreases gradually from top to bottom.
3. The modular combined constructed wetland system according to claim 2, characterized in that, The holes on the perforated wall are divided into three types according to their diameter: 10mm diameter through holes, 6mm diameter through holes, and 3mm diameter through holes. Among them, the 10mm diameter through holes are distributed in the upper region of the perforated wall; the 6mm diameter through holes are distributed in the middle region of the perforated wall; and the 3mm diameter through holes are distributed in the lower region of the perforated wall.
4. The modular combined constructed wetland system according to claim 1, characterized in that, Each wetland module (3) is equipped with a monitoring probe (6) for measuring the concentration of suspended solids in the water.
5. The modular combined constructed wetland system according to claim 1, characterized in that, The gate valve (5) is a bidirectional gate valve.
6. The modular combined constructed wetland system according to claim 1, characterized in that, The wetland module (3) is a rectangular, pentagonal, or hexagonal structure.
7. The modular combined constructed wetland system according to claim 1, characterized in that, The filler material in the wetland module (3) is arranged in the following order from bottom to top: first crushed stone layer (35), filter material layer (36), second crushed stone layer (37), and pebble layer (38).
8. The modular combined constructed wetland system according to claim 7, characterized in that, The first crushed stone layer (35) has a particle size of 30-50 mm; the filter material layer (36) has a particle size of 20-30 mm; the second crushed stone layer (37) has a particle size of 5-10 mm; and the pebble layer (38) has a particle size of 10-20 mm.
9. The modular combined constructed wetland system according to claim 8, characterized in that, The thickness of the first crushed stone layer (35) is 500 mm; the thickness of the filter material layer (36) is 400 mm; the thickness of the second crushed stone layer (37) is 300 mm; and the thickness of the pebble layer (38) is 100 mm.