A subsurface flow wetland system and a method of mitigating wetland clogging

Abstract

The present application relates to sewage treatment technical field, disclose a kind of underdrain wetland system and the method for relieving wetland blockage.The underdrain wetland system provided by the present application, by additionally adding wetland unit blockage monitoring system, automatically control the water inlet and outlet operating condition of blockage unit, make the organic matter between filler degrade faster when blockage unit low-position operation and promote microbial endogenous respiration to consume extracellular polymer or intracellular component, when water level rises, the blockage is dispersed, facilitate oxygen exchange and nutrient circulation in wetland, provide better environment for the growth of microorganism, facilitate to improve the activity of microorganism, the purification capacity of wetland is enhanced accordingly, can better remove pollutants in water;By water flow to disperse blockage, can prevent wetland from degradation due to blockage, maintain the ecological health and sustainability of wetland;Since wetland blockage is relieved, extend the service life of wetland filler, to a certain extent, the need for artificial cleaning can be reduced, thereby reducing maintenance cost.

Description

Technical Field

[0001] This invention relates to the field of wastewater treatment technology, specifically to a subsurface flow wetland system and a method for alleviating wetland clogging. Background Technology

[0002] Subsurface flow wetlands are shallow-bed wetland vegetation systems composed of gravel layers. Wastewater to be treated flows evenly and gently from one end of the packing bed through the root zone of the plants, distributed by a water distribution system. It is an ecological treatment system mainly composed of soil, wetland plants, and microorganisms. Different types of packing media and different types of purifying plants are used in the wetland according to the type of pollutants. Specifically, wastewater flows from the wetland inlet to the outlet. Because the wastewater flows below the surface, the biofilm growing on the packing surface, the abundant plant roots, and the interception effect of the packing improve the treatment effect and capacity. Furthermore, because the water flows underground, it has good heat retention, the treatment effect is less affected by air temperature, and sanitary conditions are good. Compared to surface flow wetlands, this type of wetland has a higher hydraulic load, better removal of pollutants such as BOD, COD, and SS, and produces less foul odor and less mosquito and fly breeding. Therefore, subsurface flow wetlands are widely used throughout the country for purifying polluted water bodies, including wastewater treatment plant effluent, natural water bodies of rivers and lakes, and farmland irrigation runoff.

[0003] In the actual operation of subsurface flow constructed wetlands, clogging has become one of the main factors severely restricting the lifespan and treatment effectiveness of these wetlands. According to research, most subsurface flow wetlands, both domestically and internationally, experience varying degrees of clogging after a period of operation. For example, during operation, inorganic and recalcitrant suspended solids in the wetland's influent accumulate, and the microbial sludge within the wetland contains extracellular polymers with strong cohesive power, adsorbing organic and inorganic pollutants from the influent. Furthermore, the withering and decay of aquatic plants and the resulting organic matter also contribute to clogging. Clogging of horizontal subsurface flow wetlands affects their water purification efficiency and lifespan. Moreover, restoration after clogging is complex, impacting the long-term stable operation of the wetland, posing potential risks to maintenance and management units, and ultimately affecting the application of horizontal subsurface flow wetlands. Summary of the Invention

[0004] In view of this, the present invention provides a subsurface flow wetland system and a method for alleviating wetland clogging, so as to solve the problem of the difficulty in restoring wetlands after clogging.

[0005] In a first aspect, the present invention provides a subsurface flow wetland system, comprising at least two sets of subsurface flow wetland units arranged in series and electrically controlled valves. Specifically, at least two sets of subsurface flow wetland units arranged in series are spaced apart between a wetland inlet and a wetland outlet along the direction of water flow, and adjacent sets of subsurface flow wetland units are connected by a connecting pipe; each of the connecting pipes is equipped with an electrically controlled valve; wherein each subsurface flow wetland unit is equipped with at least one water level monitoring device, and each water level monitoring device is electrically connected to a control terminal. The water level monitoring device is used to convert the measured water level into a corresponding water level signal and transmit the water level signal to the control terminal. The control terminal is used to receive the water level signal and convert the water level signal into a corresponding opening signal. The valve core of the electrically controlled valve is electrically connected to the control terminal. The control terminal is used to transmit the opening signal and control the opening degree of the valve core of the electrically controlled valve to change the throttling area of ​​the connecting pipe.

[0006] Beneficial effects: The subsurface flow wetland system provided in this application connects two adjacent subsurface flow wetland units through a connecting pipe, and an electrically controlled valve is installed on the connecting pipe. When the water level monitoring device in any subsurface flow wetland unit reports that the subsurface flow wetland unit is blocked, the control terminal controls the valve core of the electrically controlled valve to rotate, so as to adjust the water level of the subsurface flow wetland unit until the blocked subsurface flow wetland unit operates at a low water level for a period of time and then restores the water level. The wetland unit blockage monitoring system comprises connecting pipes, electrically controlled valves, water level monitoring components, and control terminals. It automatically controls the inlet and outlet operating conditions of the blockage unit, accelerating the degradation of organic matter between the packing materials and promoting endogenous respiration of microorganisms to consume extracellular polymers or intracellular components when the unit is operating at a low level. As the water level rises, it disperses the blockage particles, making the wetland's water flow channels smoother. This facilitates oxygen exchange and nutrient circulation within the wetland, providing a better environment for microbial growth and enhancing their activity. The wetland's purification capacity is also enhanced, effectively removing pollutants from the water. Simultaneously, the dispersal of blockage particles by water flow prevents wetland degradation due to blockage, maintaining the wetland's ecological health and sustainability. Furthermore, the rising water level naturally disperses blockage particles and the film produced by microorganisms, reducing the need for manual cleaning and thus lowering maintenance costs.

[0007] In one alternative implementation, a transition section is provided between two adjacent subsurface flow wetland units in the horizontal direction, the transition section connecting the two adjacent subsurface flow wetland units.

[0008] Beneficial effects: By providing a transition section between two adjacent subsurface flow wetland units in the horizontal direction, the two adjacent subsurface flow wetland units are connected, which facilitates the flow of water from the upstream subsurface flow wetland unit to the adjacent downstream subsurface flow wetland unit.

[0009] In one optional embodiment, each transition section includes a first partition wall and a second partition wall, which are horizontally spaced apart. One of the first and second partition walls is located near the upward subsurface flow wetland unit, and the other is located near the downward subsurface flow wetland unit. The bottom of the partition wall near the upward subsurface flow wetland unit is spaced apart from the bottom of the upward subsurface flow wetland unit, and the top of the partition wall near the upward subsurface flow wetland unit is higher than the top of the partition wall near the downward subsurface flow wetland unit.

[0010] Beneficial effects: In the first and second partition walls, by placing one of them close to the upward subsurface flow wetland unit in the two adjacent subsurface flow wetland units, and leaving a gap between the bottom of the partition wall of the upward subsurface flow wetland unit and the bottom of the upward subsurface flow wetland unit, the bottom of the partition wall of the upward subsurface flow wetland unit and the bottom of the upward subsurface flow wetland unit are enclosed to form a water inlet of the transition section. Furthermore, by setting the first and second partition walls horizontally, the water flow entering the water inlet can be gradually raised. Moreover, by placing the top of the partition wall near the upward subsurface flow wetland unit higher than the top of the partition wall near the downward subsurface flow wetland unit, the water flow will flow horizontally into the interior of the downward subsurface flow wetland unit after being raised to a certain height, thus realizing the movement of the water flow.

[0011] In one optional embodiment, the subsurface flow wetland system includes a packing layer and monitoring pipes. Specifically, each subsurface flow wetland unit is filled with a packing layer; each subsurface flow wetland unit is equipped with a monitoring pipe, which is vertically inserted into the packing layer, and the monitoring pipe has multiple water inlets arranged along its axial direction and / or circumferential direction; wherein, at least one water level monitoring device is installed in each monitoring pipe.

[0012] In one alternative implementation, two adjacent subsurface flow wetland units are provided with a height difference in the vertical direction.

[0013] Beneficial effects: By creating a vertical height difference between two adjacent subsurface flow wetlands, a waterfall is naturally formed as the water flows down, increasing the dissolved oxygen content in the water and improving the degradation efficiency of pollutants by microorganisms. At the same time, it avoids excessive concentration or stagnation of water in a certain area, thereby improving the overall treatment efficiency of the system. In addition, it improves the ventilation conditions between wetland units, keeping the oxygen concentration inside the wetland units high, which is conducive to the production or activity of microorganisms.

[0014] In one optional embodiment, an inlet pipe is provided at the wetland inlet.

[0015] Beneficial effects: By installing an inlet pipe at the wetland inlet, it is easier for water to flow into the subsurface flow wetland system.

[0016] In one optional embodiment, a weir is provided at the outlet of the wetland.

[0017] Beneficial effects: By installing an outlet weir at the outlet, the purified water can flow out of the subsurface flow wetland system.

[0018] Secondly, the present invention also provides a method for alleviating wetland clogging, applied to the subsurface flow wetland system of the first aspect. The method for alleviating wetland clogging includes the following steps: Preparation: Presetting a water level threshold; Identification: Real-time monitoring of the water level of each subsurface flow wetland unit; Processing: When the water level measured by any water level monitoring device exceeds the threshold, opening the connecting pipe between the subsurface flow wetland unit and its downstream subsurface flow wetland unit, allowing the subsurface flow wetland unit to operate at a low water level; Restoration: After the clogged subsurface flow wetland unit finishes operating at a low water level, restoring the flow rate of the subsurface flow wetland unit to normal.

[0019] Beneficial effects: Since the method for alleviating wetland clogging is applied to the first aspect of the subsurface flow wetland system, it has the same effect as the subsurface flow wetland system, and will not be elaborated here.

[0020] In one alternative embodiment, the preparation step may further include: increasing the porosity of the packing material; and / or adding an aeration or backwashing device at the bottom of the packing material.

[0021] Beneficial effects: By increasing the porosity of the packing material before the preparation step, the residence time of wastewater in the wetland is extended, allowing microorganisms, plants, and other organisms in the wetland to have more thorough contact with the wastewater, thereby more effectively degrading and removing pollutants. Simultaneously, it helps improve the water flow distribution within each subsurface flow wetland unit, making the water flow more uniform and reducing dead zones and short-circuiting phenomena. Furthermore, it facilitates air circulation within each subsurface flow wetland unit, increasing the dissolved oxygen content within the wetland. Additionally, by adding aeration or backwashing equipment at the bottom of the packing material, the wetland's capacity for restoration is facilitated, maintaining its ecological health and sustainability.

[0022] In one optional embodiment, the processing steps further include: turning over and drying, and replacing the packing material.

[0023] Beneficial effects: The turning and sun-drying process during treatment breaks up the compacted soil layer, increasing soil aeration and permeability, thereby improving soil structure. Simultaneously, it promotes soil microbial activity, accelerating the decomposition of organic matter and nutrient release, thus enhancing soil fertility. Furthermore, it improves the root growth environment for wetland plants, encouraging more developed root systems and facilitating water and nutrient absorption, thereby promoting plant growth and development. Replacing the packing material with new material introduces new biological communities, restoring wetland treatment efficiency and enabling continued effective pollutant removal. It also removes blockages, optimizing the wetland ecosystem. Moreover, replacing the packing material prevents system failure or performance degradation due to packing saturation or blockage, thus extending the wetland's lifespan. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the specific embodiments of the present invention, the drawings used in the description of the specific embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a top view of a subsurface flow wetland system provided in an embodiment of the present invention;

[0026] Figure 2 This is a partially enlarged top view of a subsurface flow wetland system provided in an embodiment of the present invention;

[0027] Figure 3 This is a side view of a subsurface flow wetland system provided in an embodiment of the present invention.

[0028] Explanation of reference numerals in the attached figures:

[0029] 1. Subsurface flow wetland unit;

[0030] 2. Conductor fittings;

[0031] 3. Electrically controlled valves;

[0032] 4. Water level monitoring equipment;

[0033] 51. First partition wall; 52. Second partition wall;

[0034] 61. Inlet pipe; 62. Outlet weir. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] In the description of this application, it should be understood that the terms "vertical", "horizontal", "top", "bottom", "inner", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0037] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0038] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0039] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0040] In the actual operation of subsurface flow constructed wetlands, clogging has become one of the main factors severely restricting the lifespan and treatment effectiveness of these wetlands. According to research, most subsurface flow wetlands, both domestically and internationally, experience varying degrees of clogging after a period of operation. For example, during operation, inorganic and recalcitrant suspended solids in the wetland's influent accumulate, and the microbial sludge within the wetland contains extracellular polymers with strong cohesive power, adsorbing organic and inorganic pollutants from the influent. Furthermore, the withering and decay of aquatic plants and the resulting organic matter also contribute to clogging. Clogging of horizontal subsurface flow wetlands affects their water purification efficiency and lifespan. Moreover, restoration after clogging is complex, impacting the long-term stable operation of the wetland, posing potential risks to maintenance and management units, and ultimately affecting the application of horizontal subsurface flow wetlands.

[0041] Therefore, the subsurface flow wetland system provided in this application consists of multiple subsurface flow wetland units connected in series, and it solves blockages and promotes the restoration of the purification efficiency of the horizontal subsurface flow wetland by monitoring and adjusting the water volume and water level in each subsurface flow wetland unit.

[0042] Specifically, please refer to Figures 1 to 3 , Figure 1 A top view of the subsurface flow wetland system provided in this application is shown; Figure 2 This paper shows a partially enlarged top view of the subsurface flow wetland system provided in this application; Figure 3 A side view of the subsurface flow wetland system provided in this application is shown.

[0043] The following is combined Figures 1 to 3 The following describes embodiments of the present invention.

[0044] Firstly, this application provides a subsurface flow wetland system, such as Figures 1 to 3 As shown, the subsurface flow wetland system includes at least two sets of subsurface flow wetland units 1 arranged in series and electrically controlled valves 3. Specifically, at least two sets of subsurface flow wetland units 1 arranged in series are spaced apart between the wetland inlet and the wetland outlet along the direction of water flow, and adjacent sets of subsurface flow wetland units 1 are connected by a connecting pipe 2; each connecting pipe 2 is equipped with an electrically controlled valve 3; each subsurface flow wetland unit 1 is equipped with at least one water level monitoring device 4, and each water level monitoring device 4 is electrically connected to a control terminal. The water level monitoring device 4 is used to convert the measured water level into a corresponding water level signal and transmit the water level signal to the control terminal. The control terminal is used to receive the water level signal and convert the water level signal into a corresponding opening signal. The valve core of the electrically controlled valve 3 is electrically connected to the control terminal. The control terminal is used to transmit the opening signal toward the electrically controlled valve 3 and control the opening degree of the valve core of the electrically controlled valve 3 to change the throttling area of ​​the connecting pipe 2.

[0045] Using the subsurface flow wetland system provided in this embodiment, two adjacent subsurface flow wetland units 1 are connected by a connecting pipe 2, and an electrically controlled valve 3 is provided on the connecting pipe 2. When the water level monitoring device 4 in any subsurface flow wetland unit 1 reports that the subsurface flow wetland unit 1 is blocked, the control terminal controls the valve core of the electrically controlled valve 3 to rotate, so as to adjust the water level of the subsurface flow wetland unit 1 until the blocked subsurface flow wetland unit 1 operates at a low water level for a period of time and then the water level is restored.

[0046] The wetland unit blockage monitoring system comprises the following components: the guide pipe 2, the electrically controlled valve 3, the water level monitoring component 4, and the control terminal. This system automatically controls the inlet and outlet water conditions of the blocked unit. When the blocked unit is operating at a low level, it accelerates the degradation of organic matter between the packing materials and promotes endogenous respiration of microorganisms, consuming extracellular polymers or intracellular components. This allows the kinetic energy of the water to dissipate the blockage particles when the water level rises, making the wetland's water flow channels smoother. This facilitates oxygen exchange and nutrient circulation within the wetland, providing a better environment for microbial growth and enhancing their activity. The wetland's purification capacity is also strengthened, effectively removing pollutants from the water. Simultaneously, the dispersal of blockage particles by water flow prevents wetland degradation due to blockage, maintaining the wetland's ecological health and sustainability. Furthermore, the rising water level naturally disperses blockage particles and the film produced by microorganisms, reducing the need for manual cleaning and thus lowering maintenance costs.

[0047] It should be noted that the number of water level monitoring devices 4 in each subsurface flow wetland unit 1 is not specifically limited in the subsurface flow wetland system provided in this application.

[0048] For example, when there is one water level monitoring device 4 in a subsurface flow wetland unit 1, the water level monitoring device 4 is installed in the center. Of course, when there are at least two water level monitoring devices 4 in a subsurface flow wetland unit 1, the at least two water level monitoring devices 4 are arranged in a matrix array. With this setting, by collecting the blockage information in each subsurface flow wetland unit 1 and quickly providing feedback, the location of the blockage can be quickly determined. If the blockage is subsequently resolved by adjusting the water level, the location information of the blockage can also be used to resolve the blockage through maintenance measures such as replacing the packing material.

[0049] It can be noted that in this application, there is a transition section between two adjacent subsurface flow wetland units 1 in the horizontal direction, and the transition section connects the two adjacent subsurface flow wetland units 1.

[0050] Using the subsurface flow wetland system provided in this embodiment, a transition section is provided between two adjacent subsurface flow wetland units 1 in the horizontal direction to connect the two adjacent subsurface flow wetland units 1, so that water flow can flow from the upstream subsurface flow wetland unit to the adjacent downstream subsurface flow wetland unit.

[0051] like Figures 1 to 3 As shown, each transition section includes a first partition wall 51 and a second partition wall 52. The first partition wall 51 and the second partition wall 52 are arranged at intervals in the horizontal direction. In the first partition wall 51 and the second partition wall 52, one of them is arranged in the upstream subsurface flow wetland unit, and the other of them is arranged close to the downstream subsurface flow wetland unit.

[0052] Specifically, a gap is left between the bottom of the partition wall near the upward subsurface flow wetland unit and the bottom of the upward subsurface flow wetland unit, and the top of the partition wall near the upward subsurface flow wetland unit is higher than the top of the partition wall near the downward subsurface flow wetland unit.

[0053] Using the subsurface flow wetland system provided in this embodiment, in the first partition wall 51 and the second partition wall 52, one of them is set close to the upward subsurface flow wetland unit, and a gap is left between the bottom of the partition wall of the upward subsurface flow wetland unit and the bottom of the upward subsurface flow wetland unit, so that the bottom of the partition wall of the upward subsurface flow wetland unit and the bottom of the upward subsurface flow wetland unit enclose the water inlet of the transition section. Furthermore, by setting the first partition wall 51 and the second partition wall 52 at a horizontal interval, the water entering the water inlet can be gradually raised. Furthermore, by setting the top of the partition wall near the upward subsurface flow wetland unit higher than the top of the partition wall near the downward subsurface flow wetland unit, the water will flow horizontally into the interior of the downward subsurface flow wetland unit after being raised to a certain height, thereby realizing the movement of the water flow.

[0054] It can be noted that the aforementioned connecting pipe 2 can be selected as an overpass pipe and equipped with an electrically controlled valve 3, which can adjust the water volume and water level of each unit individually.

[0055] It can be noted that, in order to improve the accuracy of the detection results of the water level monitoring device 4, the subsurface flow wetland system includes a filler layer and monitoring pipes.

[0056] Specifically, each subsurface flow wetland unit 1 is filled with a packing layer; each subsurface flow wetland unit 1 is equipped with a monitoring pipe, which is inserted vertically into the packing layer, and the monitoring pipe is provided with multiple water inlets, which are arranged along its axial direction and / or circumferential direction; wherein, at least one water level monitoring device 4 is installed in each monitoring pipe.

[0057] Using the subsurface flow wetland system provided in this embodiment, by filling a packing layer in any subsurface flow wetland unit 1 and vertically inserting a monitoring pipe with multiple water inlets into the packing layer, the water level in the monitoring pipe can be used to determine the water level height in the subsurface flow wetland unit 1, making it easier to determine whether the subsurface flow wetland where the monitoring pipe is located is blocked.

[0058] Furthermore, multiple water inlets are evenly distributed along their axial and circumferential directions to ensure uniform exchange between the monitoring pipes and the water flow inside the subsurface flow wetland unit 1.

[0059] It can be explained that in this application, a water level monitoring device 4 is installed inside each monitoring pipe. The water level monitoring device 4 can be selected as a liquid level sensor, such as a common submersible liquid level sensor. The water level height inside the monitoring pipe is determined by water pressure. When in use, a liquid level is preset only in the vertical direction (height direction) as a threshold. This threshold can be determined by adding a certain height to the liquid level value during initial normal operation (without blockage) or by being 1-2 cm higher than the surface of the packing as a standard for judging blockage.

[0060] like Figure 3 As shown, two adjacent subsurface wetland units 1 are provided with a height difference in the vertical direction.

[0061] The subsurface flow wetland system provided in this embodiment creates a vertical height difference between two adjacent subsurface flow wetlands, allowing the water to naturally form a waterfall as it flows downwards. This increases the dissolved oxygen content in the water, improves the degradation efficiency of pollutants by microorganisms, and prevents water from becoming excessively concentrated or stagnant in a certain area, thereby improving the overall system's treatment efficiency. In addition, it improves ventilation between wetland units, maintaining a high oxygen concentration inside the wetland units, which is beneficial for the production or activity of microorganisms.

[0062] like Figure 1 and Figure 3 As shown, an inlet pipe channel 61 is provided at the wetland inlet.

[0063] The subsurface flow wetland system provided in this embodiment facilitates water flow into the subsurface flow wetland system by providing an inlet pipe channel 61 at the inlet.

[0064] Still Figure 1 and Figure 3 As shown, a weir 62 is provided at the outlet of the wetland.

[0065] Using the subsurface flow wetland system provided in this embodiment, a weir 62 is provided at the outlet to facilitate the flow of purified water out of the subsurface flow wetland system.

[0066] Under normal operating conditions, the subsurface flow wetland system provided above distributes incoming water to the first subsurface flow wetland unit 1 near the inlet through the inlet pipe 61. The treated water then enters the next wetland unit through the bottom channel of the first partition wall 51. After being treated by multiple units, the water finally exits through the outlet weir 62.

[0067] Furthermore, the aforementioned subsurface flow wetland system includes a flushing device installed within each subsurface flow wetland unit 1. For example, the flushing device can be a flushing pipe. This flushing pipe can be arranged in a forward direction, from the higher side of the subsurface flow wetland unit 1 towards the lower side. This arrangement simulates the natural flow of water within the wetland, helping to maintain the stability and naturalness of the wetland's ecosystem and achieving uniform flushing, avoiding over- or under-flushing in certain areas. Alternatively, the flushing pipe can be arranged in a reverse direction, from the lower side of the subsurface flow wetland unit 1 towards the higher side. This arrangement facilitates deep cleaning, effectively removing long-term accumulated blockages, helping the wetland restore its proper treatment capacity, and allowing water to flow smoothly through the treatment areas within the wetland, thereby improving the wetland's treatment efficiency. Simultaneously, it protects the wetland's ecosystem and treatment facilities, thus extending the wetland's lifespan.

[0068] Secondly, this application also provides a method for alleviating wetland clogging, applied to the subsurface flow wetland system of the first aspect.

[0069] The method for alleviating wetland blockage combines the preset water level warning line of each subsurface flow wetland unit 1 with the real-time water level monitoring device 4.

[0070] Specifically, the method for mitigating wetland blockage includes stages such as preparation, identification, treatment, and restoration.

[0071] The process includes: preparation (presetting a water level threshold); identification (each water level monitoring device 4 monitors the water level of its respective subsurface flow wetland unit 1 in real time); handling (when the water level measured by any water level monitoring device 4 exceeds the threshold, the connecting pipe 2 between the subsurface flow wetland unit 1 and its downstream subsurface flow wetland unit 1 is opened, allowing the subsurface flow wetland unit 1 to operate at a low water level); and restoration (after the low water level operation of the blocked subsurface flow wetland unit 1 ends, the flow rate of the subsurface flow wetland unit 1 is restored to normal).

[0072] It can be explained that the water level monitoring device 4 is used to convert the measured water level into a corresponding water level signal and transmit the water level signal to the control terminal. The control terminal is used to receive the water level signal and convert the water level signal into a corresponding opening signal. The valve core of the electrically controlled valve 3 is electrically connected to the electric actuator. The electric actuator is used to receive the opening signal and control the opening degree of the valve core of the electrically controlled valve 3 to change the throttling area of ​​the guide pipe 2.

[0073] That is, the control terminal receives the real-time water level signal, and when the water level signal exceeds the threshold, it increases the opening degree of the valve core of the electrically controlled valve 3, thereby reducing the water level of this subsurface flow wetland unit 1, and runs at a low water level for a period of time according to the preset program. After the low water level operation ends, the normal flow rate of each wetland unit is restored.

[0074] It can be noted that the preparation steps also include: increasing the porosity of the packing; and / or adding aeration or backwashing equipment at the bottom of the packing.

[0075] The method for alleviating wetland clogging provided in this embodiment increases the porosity of the packing material before the preparation step, extending the residence time of wastewater in the wetland. This allows microorganisms, plants, and other organisms in the wetland to have more thorough contact with the wastewater, thereby more effectively degrading and removing pollutants. Simultaneously, it helps improve the water flow distribution within each subsurface flow wetland unit 1, making the water flow more uniform and reducing dead zones and short-circuiting phenomena. Furthermore, it facilitates air circulation within each subsurface flow wetland unit 1, increasing the dissolved oxygen content within the wetland. Adding aeration or backwashing equipment at the bottom of the packing material further facilitates the restoration of the wetland's capacity, maintaining its ecological health and sustainability.

[0076] Specifically, the backwashing equipment includes water pipes and a water pump. The water pipes are located downstream of the subsurface flow wetland unit and are laid out with their water outlet direction facing upstream. The water pump drives the water flow for backwashing to flow upstream.

[0077] It should be noted that the processing steps also include: turning over and drying, and replacing the packing material.

[0078] The method for alleviating wetland clogging provided in this embodiment utilizes a process where turning and sun-drying the soil breaks up the compacted soil layer, increasing soil aeration and permeability, thereby improving soil structure. Simultaneously, it promotes soil microbial activity, accelerating the decomposition of organic matter and nutrient release, thus enhancing soil fertility. Furthermore, it improves the root growth environment for wetland plants, leading to more developed root systems and facilitating the absorption of water and nutrients, thereby promoting plant growth and development. Replacing the filler with new material introduces new biological communities, restoring wetland treatment efficiency and enabling continued effective pollutant removal. It also removes blockages, optimizing the wetland ecosystem. Moreover, replacing the filler with new material prevents system failure or performance degradation due to filler saturation or clogging, thus extending the wetland's lifespan.

[0079] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A subsurface flow wetland system, characterized in that, include: At least two sets of subsurface flow wetland units (1) are arranged in series. At least two sets of subsurface flow wetland units (1) are arranged in series between the wetland inlet and the wetland outlet along the direction of water flow. Two adjacent sets of subsurface flow wetland units (1) are connected by a connecting pipe (2). An electrically controlled valve (3) is provided on any of the aforementioned conductive pipe fittings (2); In this context, each subsurface flow wetland unit (1) is equipped with at least one water level monitoring device (4), and each of the water level monitoring devices (4) is electrically connected to the control terminal. The water level monitoring device (4) is used to convert the measured water level into a corresponding water level signal and transmit the water level signal to the control terminal. The control terminal is used to receive the water level signal and convert the water level signal into a corresponding opening signal. The valve core of the electrically controlled valve (3) is electrically connected to the control terminal. The control terminal is used to transmit the opening signal and control the opening degree of the valve core of the electrically controlled valve (3) to change the throttling area of ​​the connecting pipe (2). A transition section is provided between two adjacent subsurface flow wetland units (1) in the horizontal direction, and the transition section connects the two adjacent subsurface flow wetland units (1); Each transition section includes a first partition wall (51) and a second partition wall (52), the first partition wall (51) and the second partition wall (52) are arranged at intervals in the horizontal direction, and one of the first partition wall (51) and the second partition wall (52) is arranged close to the upward subsurface flow wetland unit, and the other of the two is arranged close to the downward subsurface flow wetland unit; Among them, the bottom of the partition wall near the upward subsurface flow wetland unit is separated from the bottom of the upward subsurface flow wetland unit, and the top of the partition wall near the upward subsurface flow wetland unit is higher than the top of the partition wall near the downward subsurface flow wetland unit. The conductive pipe (2) is a bypass pipe.

2. The subsurface flow wetland system according to claim 1, characterized in that, Also includes: The filler layer is filled in any subsurface flow wetland unit (1); Monitoring pipe fittings are provided in any group of subsurface flow wetland units (1). The monitoring pipe fittings are inserted vertically into the packing layer, and the monitoring pipe fittings are provided with multiple water inlets, which are arranged along their axial direction and / or circumferential direction. Among them, at least one water level monitoring device (4) is installed inside any of the monitoring pipe fittings.

3. The subsurface flow wetland system according to claim 1 or 2, characterized in that, The two adjacent subsurface wetland units (1) have a height difference in the vertical direction.

4. The subsurface flow wetland system according to claim 1 or 2, characterized in that, The wetland is equipped with an inlet pipe (61).

5. The subsurface flow wetland system according to claim 1 or 2, characterized in that, The wetland outlet is equipped with an outlet weir (62).

6. A method for alleviating wetland clogging, applied to the subsurface flow wetland system according to any one of claims 1-5, characterized in that, The method for alleviating wetland clogging includes the following steps: Preparation: Preset water level threshold; Identification: Each water level monitoring unit (4) monitors the water level of its local subsurface flow wetland unit (1) in real time; Handling: When the water level measured by any water level monitoring device (4) exceeds the threshold, open the connecting pipe (2) between the subsurface flow wetland unit (1) and its downstream subsurface flow wetland unit (1) to make the subsurface flow wetland unit (1) operate at a low water level; Restoration: After the low water level operation of the subsurface flow wetland unit (1) to be blocked is completed, restore the flow rate of the subsurface flow wetland unit (1) to the normal state.

7. The method for alleviating wetland clogging according to claim 6, characterized in that, The preparation steps also include: increasing the porosity of the packing; and / or adding aeration or backwashing equipment at the bottom of the packing.

8. The method for alleviating wetland clogging according to claim 6, characterized in that, The processing steps also include: Turn over and dry, and replace the packing material.

Images