Subsurface wetland system and method for relieving wetland blockage

Abstract

The invention relates to the technical field of sewage treatment, and discloses a subsurface wetland system and a method for relieving wetland blockage. According to the subsurface wetland system provided by the invention, the wetland unit blockage monitoring system is additionally arranged, and the water inlet and outlet operation conditions of the blockage unit are automatically controlled, so that when the blockage unit operates at a low position, the degradation of organic matters among fillers is accelerated, the endogenous respiration of microorganisms is promoted to consume extracellular polymers or intracellular components, and blockages are dispersed when the water level rises; oxygen exchange and circulation of nutrient substances in the wetland are facilitated, a better environment is provided for growth of microorganisms, the activity of the microorganisms is conveniently improved, the purification capacity of the wetland is correspondingly enhanced, and pollutants in water can be better removed; blockages are dispersed by water flow, so that the wetland can be prevented from being degraded due to blockage, and the ecological health and sustainability of the wetland are kept; and as the wetland blockage is relieved, the service life of the wetland filler is prolonged, and the requirement of manual cleaning can be reduced to a certain extent, so that the maintenance cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of sewage treatment, and in particular to a subsurface flow wetland system and a method for alleviating wetland blockage. Background Art

[0002] Subsurface flow wetland is a shallow bed-wetland plant system composed of gravel layers. The treated wastewater is distributed by the water distribution system and flows evenly and gently from one end of the packing bed through the plant root zone of the packing bed. It is an ecological treatment system mainly composed of soil, wetland plants and microorganisms. Different types of packing media are used in wetlands according to the types of pollutants and different types of purification plants are planted. Specifically, sewage flows from one end of the wetland water inlet to one end of the wetland water outlet. Since the sewage flows below the surface, on the one hand, the biofilm grown on the surface of the packing, the rich plant root system and the interception of the packing can be used to improve the treatment effect and treatment capacity; on the other hand, since the water flows below the surface, it has good thermal insulation, the treatment effect is less affected by the temperature, and the sanitary conditions are good. Compared with surface flow wetlands, this type of wetland has a larger hydraulic load, better removal effect on pollution indicators such as BOD, COD, SS, and less odor and breeding of mosquitoes and flies. Therefore, subsurface wetlands are widely used throughout the country to purify polluted water bodies, including tailwater from sewage treatment plants, natural water bodies in rivers and lakes, and drainage water from agricultural irrigation.

[0003] In the actual operation of subsurface artificial wetlands, wetland blockage has become one of the main factors that seriously restrict the service life and treatment effect of subsurface wetlands. According to investigations and studies, most subsurface wetlands at home and abroad will experience varying degrees of blockage after a period of operation. For example, during operation, inorganic and difficult-to-degrade suspended matter in the wetland influent will accumulate in the subsurface wetland. The microbial sludge inside the wetland contains extracellular polymers, which have strong cohesion and adsorb organic and inorganic pollutants in the influent. In addition, organic matter produced by the withering and corruption of aquatic plants in the wetland will cause blockage of horizontal subsurface wetlands. Blockage of horizontal subsurface wetlands will affect the water purification effect of the wetland and affect the service life of the wetland. At the same time, after the horizontal subsurface wetland is blocked, it is more troublesome to recover, which affects the long-term and stable operation of the horizontal subsurface wetland, brings potential risks to the operation and maintenance management unit, and affects the application of horizontal subsurface 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 blockage to solve the problem that wetland recovery after blockage is troublesome.

[0005] In the first aspect, the present invention provides a submerged wetland system, comprising at least two groups of submerged wetland units arranged in series and an electrically controlled valve. Specifically, at least two groups of submerged wetland units arranged in series are arranged between a wetland water inlet and a wetland water outlet along the flow direction of the water flow, and two adjacent groups of submerged wetland units are connected by a conducting pipe; an electrically controlled valve is provided on any of the conducting pipes; wherein at least one water level monitoring component is provided in any of the submerged wetland units, and any of the water level monitoring components is electrically connected to a control terminal, and the water level monitoring component is used to convert the measured water level into a corresponding water level signal and transmit the water level signal to the control terminal, and the control terminal is used to receive the water level signal and convert the water level signal into a corresponding opening signal, and the valve core of the electrically controlled valve is electrically connected to the control terminal, and 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 conducting pipe.

[0006] Beneficial effects: The submerged flow wetland system provided by the present application enables two adjacent groups of submerged flow wetland units to be connected through a conducting pipe, and an electrically controlled valve is provided on the conducting pipe. When a water level monitoring component in any submerged flow wetland unit feeds back that the submerged flow wetland unit is blocked, the control terminal controls the valve core of the electrically controlled valve to rotate to adjust the water level of the submerged flow wetland unit until the blocked submerged flow wetland unit runs at a low water level for a period of time and then restores the water level. Among them, the conducting pipe fittings, electric control valves, water level detection components, and control terminals constitute the wetland unit blockage monitoring system, which automatically controls the water inlet and outlet operating conditions of the blockage unit, so that when the blockage unit runs at a low level, it accelerates the degradation of organic matter between the fillers and promotes the endogenous respiration of microorganisms to consume extracellular polymers or intracellular components. When the water level rises, the blocked particles will be dispersed, making the water flow channel of the wetland more unobstructed, which is conducive to the oxygen exchange and nutrient circulation inside the wetland, providing a better environment for the growth of microorganisms, facilitating the improvement of microbial activity, and the purification capacity of the wetland will be correspondingly enhanced, which can better remove pollutants in the water; at the same time, by dispersing the blocking particles through water flow, the wetland can be prevented from being degraded due to blockage, thereby maintaining the ecological health and sustainability of the wetland; in addition, the blocking particles and the film produced by microorganisms can be naturally dispersed during the water level rise, which can reduce the need for manual cleaning to a certain extent, thereby reducing maintenance costs.

[0007] In an optional embodiment, a transition section is provided between two adjacent groups of submerged flow wetland units in the horizontal direction, and the transition section connects the two adjacent groups of submerged flow wetland units.

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

[0009] In an optional embodiment, each transition section includes a first partition wall and a second partition wall, and the first partition wall and the second partition wall are spaced apart in the horizontal direction. Among the first partition wall and the second partition wall, one of them is arranged close to the ascending submerged flow wetland unit, and the other of them is arranged close to the descending submerged flow wetland unit; wherein, a gap is left between the bottom of the partition wall close to the ascending submerged flow wetland unit and the bottom of the ascending submerged flow wetland unit, and a top of the partition wall close to the ascending submerged flow wetland unit is higher than a top of the partition wall close to the descending submerged flow wetland unit.

[0010] Beneficial effect: In the first partition wall and the second partition wall, one of the two is arranged close to the ascending submerged flow wetland unit in the two adjacent groups of submerged flow wetland units, and a gap is left between the bottom of the partition wall of the ascending submerged flow wetland unit and the bottom of the ascending submerged flow wetland unit, so that the bottom of the partition wall of the ascending submerged flow wetland unit and the bottom of the ascending submerged flow wetland unit are enclosed to form a water flow inlet of the transition section, and the first partition wall and the second partition wall are arranged horizontally at intervals so that the water flow entering the water flow inlet can be gradually lifted, and the top of the partition wall close to the ascending submerged flow wetland unit is higher than the top of the partition wall close to the descending submerged flow wetland unit, so that the water flow will flow horizontally to the interior of the descending submerged flow wetland unit after being lifted to a certain height, thereby realizing the movement of the water flow.

[0011] In an optional embodiment, the submerged wetland system includes a packing layer and a monitoring pipe. Specifically, any group of submerged wetland units is filled with a packing layer; any group of submerged wetland units is provided with a monitoring pipe, the monitoring pipe is vertically inserted into the packing layer, and the monitoring pipe is provided with a plurality of water inlets, which are arranged along the axial direction and / or the circumferential direction; wherein at least one water level monitoring component is installed in any of the monitoring pipes.

[0012] In an optional embodiment, two adjacent groups of subsurface flow wetland units are provided with a height difference in the vertical direction.

[0013] Beneficial effects: By setting a height difference between two adjacent groups of subsurface wetlands in the vertical direction, waterfalls are naturally formed in the process of water flow, which increases the dissolved oxygen content in the water body and improves the degradation efficiency of pollutants by microorganisms. At the same time, it avoids excessive concentration or retention of water in a certain area, thereby improving the treatment efficiency of the entire system. In addition, the ventilation conditions between wetland units are improved, so that a higher oxygen concentration is maintained inside the wetland units, which is conducive to the production or activity of microorganisms.

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

[0015] Beneficial effects: By providing an inlet pipe at the wetland water inlet, it is convenient for water to enter the subsurface wetland system.

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

[0017] Beneficial effect: By providing a water outlet weir at the water outlet, it is convenient for the purified water to flow out of the subsurface wetland system.

[0018] In the second aspect, the present invention also provides a method for alleviating wetland blockage, which is applied to the submerged wetland system of the first aspect, and the method for alleviating wetland blockage includes the following steps. Preparation: preset water level threshold; identification: each water level monitoring component monitors the water level of the submerged wetland unit in real time; processing: when the water level measured by any water level monitoring component exceeds the threshold, open the conducting pipe between the submerged wetland unit and its downstream submerged wetland unit, so that the submerged wetland unit operates at a low water level; recovery: after the submerged wetland unit to be blocked ends its low water level operation, restore the flow of the submerged wetland unit to a normal state.

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

[0020] In an optional embodiment, the preparation step further includes: increasing the porosity of the filler; and / or adding an aeration or backwashing device at the bottom of the filler.

[0021] Beneficial effects: By increasing the porosity of the filler before the preparation step, the residence time of sewage in the wetland is prolonged, which facilitates the microorganisms, plants and other organisms in the wetland to contact the sewage more fully, thereby more effectively degrading and removing pollutants; at the same time, it helps to improve the water flow distribution inside each submerged wetland unit, making the water flow more uniform and reducing the occurrence of dead zones and short circuits; in addition, it is conducive to the circulation of air in each submerged wetland unit and increasing the dissolved oxygen content inside the wetland. By adding aeration or backwashing equipment at the bottom of the filler, it is easy to restore the capacity of the wetland and maintain the ecological health and sustainability of the wetland.

[0022] In an optional embodiment, the processing step also includes: turning over and drying, and replacing fillers.

[0023] Beneficial effects: Turning and drying the wetland soil during the treatment process can help break the compacted layer of the wetland soil, increase the air permeability and water permeability of the soil, and thus improve the soil structure; at the same time, by promoting the activity of soil microorganisms, the decomposition of organic matter and the release of nutrients are accelerated, and the soil fertility is improved; in addition, the root growth environment of wetland plants can be improved, making the root system more developed, which is conducive to the absorption of water and nutrients by plants, thereby promoting the growth and development of plants. By replacing new fillers, new biological communities can be introduced, and the treatment efficiency of the wetland can be restored, so that it can continue to effectively remove pollutants; at the same time, blockages can be removed and the wetland ecology can be optimized; in addition, by replacing new fillers, system failure or performance degradation caused by filler saturation or blockage can be avoided, thereby extending the service life of the wetland. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the specific implementation modes of the present invention, the drawings required for use in the description of the specific implementation modes will be briefly introduced below. Obviously, the drawings described below are some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 A top view of a submerged flow wetland system provided by an embodiment of the present invention;

[0026] Figure 2 A partially enlarged schematic top view of a subsurface wetland system provided by an embodiment of the present invention;

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

[0028] Description of reference numerals:

[0029] 1. Subsurface wetland unit;

[0030] 2. Conductive pipe fittings;

[0031] 3. Electronically controlled valve;

[0032] 4. Water level monitoring components;

[0033] 51. first partition wall; 52. second partition wall;

[0034] 61. Inlet pipe; 62. Outlet weir. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0036] In the description of the present application, it should be understood that the terms "vertical", "horizontal", "top", "bottom", "inside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

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

[0038] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0039] In addition, 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 artificial wetlands, wetland blockage has become one of the main factors that seriously restrict the service life and treatment effect of subsurface wetlands. According to investigations and studies, most subsurface wetlands at home and abroad will experience varying degrees of blockage after a period of operation. For example, during operation, inorganic and difficult-to-degrade suspended matter in the wetland influent will accumulate in the subsurface wetland. The microbial sludge inside the wetland contains extracellular polymers, which have strong cohesion and adsorb organic and inorganic pollutants in the influent. In addition, organic matter produced by the withering and corruption of aquatic plants in the wetland will cause blockage of horizontal subsurface wetlands. Blockage of horizontal subsurface wetlands will affect the water purification effect of the wetland and affect the service life of the wetland. At the same time, after the horizontal subsurface wetland is blocked, it is more troublesome to recover, which affects the long-term and stable operation of the horizontal subsurface wetland, brings potential risks to the operation and maintenance management unit, and affects the application of horizontal subsurface wetlands.

[0041] To this end, the subsurface flow wetland system provided in the present application is composed of multiple groups of subsurface flow wetland units connected in series, and it solves the blockage and promotes the restoration of purification efficiency of horizontal subsurface flow wetlands by monitoring and adjusting the water volume and water level in each subsurface flow wetland unit.

[0042] Specifically, see Figures 1 to 3 , Figure 1 A top view of the subsurface wetland system provided by the present application is shown; Figure 2 A partial enlarged top view schematic diagram of the subsurface flow wetland system provided by the present application is shown; Figure 3 A side view of the subsurface flow wetland system provided by the present application is shown.

[0043] Combine the following Figures 1 to 3 , describing an embodiment of the present invention.

[0044] In a first aspect, the present application provides a subsurface wetland system, such as Figures 1 to 3 As shown, the submerged wetland system includes at least two groups of submerged wetland units 1 arranged in series and an electrically controlled valve 3. Specifically, at least two groups of submerged wetland units 1 arranged in series are arranged between the wetland water inlet and the wetland water outlet along the flow direction of the water flow, and the two adjacent groups of submerged wetland units 1 are connected through the conducting pipe 2; an electrically controlled valve 3 is provided on any conducting pipe 2; wherein, at least one water level monitoring component 4 is provided in any submerged wetland unit 1, and any water level monitoring component 4 is electrically connected to the control terminal, and the water level monitoring component 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, and the control terminal is used to receive the water level signal and convert the water level signal into a corresponding opening signal, and the valve core of the electrically controlled valve 3 is electrically connected to the control terminal, and the control terminal is used to transmit the opening signal toward one side of 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 conducting pipe 2.

[0045] Utilizing the submerged flow wetland system provided in this embodiment, two adjacent groups of submerged flow wetland units 1 are connected via a conducting pipe 2, and an electrically controlled valve 3 is provided on the conducting pipe 2. When a water level monitoring component 4 in any submerged flow wetland unit 1 feeds back that the submerged flow wetland unit 1 is blocked, the control terminal controls the valve core of the electrically controlled valve 3 to rotate to adjust the water level of the submerged flow wetland unit 1 until the blocked submerged flow wetland unit 1 runs at a low water level for a period of time and then restores the water level.

[0046] Among them, the conducting pipe fittings 2, the electric control valves 3, the water level monitoring components 4, and the control terminals constitute the wetland unit blockage monitoring system, which automatically controls the water inlet and outlet operating conditions of the blocked unit, so that when the blocked unit runs at a low position, it accelerates the degradation of organic matter between the fillers and promotes the endogenous respiration of microorganisms to consume extracellular polymers or intracellular components, so that when the water level rises, the kinetic energy of the blocked particles can be used to disperse the blocked particles, making the water flow channel of the wetland more unobstructed, which is conducive to the oxygen exchange and nutrient circulation inside the wetland, providing a better environment for the growth of microorganisms, and facilitating the improvement of the activity of microorganisms. The purification capacity of the wetland will also be enhanced accordingly, and pollutants in the water can be better removed; at the same time, by dispersing the blocked particles through water flow, the wetland can be prevented from being degraded due to blockage, and the ecological health and sustainability of the wetland can be maintained; in addition, the blocked particles and the film produced by the microorganisms can be naturally dispersed during the water level rise, which can reduce the need for manual cleaning to a certain extent, thereby reducing maintenance costs.

[0047] It can be explained that the submerged flow wetland system provided in the present application does not specifically limit the number of water level detection components in each submerged flow wetland unit 1 .

[0048] For example, when there is one water level detection member in the submerged wetland unit 1, the water level detection member is installed in the center. Of course, when there are at least two water level detection members in the submerged wetland unit 1, at least two water level detection members are arranged in a matrix array. In this way, the blockage situation in each submerged wetland unit 1 is collected and quickly fed back, that is, the location where the blockage occurs can be quickly determined. If the water level is subsequently adjusted to solve the blockage, the blockage can also be solved by operation and maintenance means such as filler replacement in combination with the location information of the blockage.

[0049] It can be explained that, in the present application, a transition section is provided between two adjacent groups of subsurface flow wetland units 1 in the horizontal direction, and the transition section connects the two adjacent groups of subsurface flow wetland units 1 .

[0050] Utilizing the submerged flow wetland system provided in this embodiment, a transition section is provided between two adjacent groups of submerged flow wetland units 1 in the horizontal direction so that the two adjacent groups of submerged flow wetland units 1 are connected, thereby facilitating the flow of water from the upstream submerged flow wetland unit to the adjacent downstream submerged 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, and 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 the two is arranged in the upstream submerged wetland unit, and the other is arranged close to the downstream submerged wetland unit.

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

[0053] Utilizing the submerged flow wetland system provided in the present embodiment, in the first partition wall 51 and the second partition wall 52, one of the two is arranged close to the ascending submerged flow wetland unit, and a gap is left between the bottom of the partition wall of the ascending submerged flow wetland unit and the bottom of the ascending submerged flow wetland unit, so that the bottom of the partition wall of the ascending submerged flow wetland unit and the bottom of the ascending submerged flow wetland unit are enclosed to form a water flow inlet of the transition section, and the first partition wall 51 and the second partition wall 52 are arranged horizontally at intervals so that the water flow entering the water flow inlet can be gradually lifted, and the top of the partition wall close to the ascending submerged flow wetland unit is higher than the top of the partition wall close to the descending submerged flow wetland unit, so that the water flow will flow horizontally to the interior of the descending submerged flow wetland unit after being lifted to a certain height, thereby realizing the movement of the water flow.

[0054] It can be explained that the above-mentioned conducting pipe 2 can be selected as a bypass pipe and matched with an electric control valve 3, so that the water volume and water level of each unit can be adjusted individually.

[0055] It can be explained that, in order to improve the accuracy of the detection results of the water level monitoring component 4, the submerged flow wetland system includes a filler layer and a monitoring pipe.

[0056] Specifically, any group of submerged flow wetland units 1 is filled with a filler layer; any group of submerged flow wetland units 1 is provided with a monitoring pipe fitting, the monitoring pipe fitting is inserted into the filler layer in a vertical direction, and the monitoring pipe fitting is provided with a plurality of water inlet holes, and the plurality of water inlet holes are arranged along the axial direction and / or the circumferential direction; wherein, at least one water level monitoring component 4 is installed in any monitoring pipe fitting.

[0057] By utilizing the submerged flow wetland system provided in this embodiment, a filling layer is filled in any submerged flow wetland unit 1, and a monitoring pipe with multiple water inlet holes is vertically inserted into the filling layer. The water level in the monitoring pipe can be used to know the water level height of the submerged flow wetland unit 1 area, which is convenient for judging whether the submerged flow wetland where the monitoring pipe is located is blocked.

[0058] Furthermore, a plurality of water inlet holes are evenly distributed along the axial direction and the circumferential direction thereof, so that the monitoring pipe can be evenly exchanged with the water flow inside the submerged flow wetland unit 1 .

[0059] It can be explained that in the present application, a water level detection component is installed inside each monitoring pipe fitting. The water level detection component can be selected as a liquid level sensor, such as the common immersion liquid level sensor, which determines the water level height inside the monitoring pipe fitting by water pressure. When in use, only a liquid level is preset in the vertical direction (height direction) as a threshold. This threshold can be the liquid level value during initial normal operation (unblocked) plus a certain height or 1-2 cm higher than the filler surface as a standard for judging blockage.

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

[0061] By utilizing the subsurface flow wetland system provided in this embodiment, by providing a height difference in the vertical direction between two adjacent groups of subsurface flow wetlands, a waterfall is naturally formed in the process of water flow descending, thereby increasing the dissolved oxygen content in the water body and improving the degradation efficiency of pollutants by microorganisms. At the same time, excessive concentration or retention of water flow in a certain area is avoided, thereby improving the treatment efficiency of the entire system. In addition, the ventilation conditions between wetland units are improved, so that a higher oxygen concentration is maintained inside the wetland units, which is conducive to the production or activity of microorganisms.

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

[0063] The submerged flow wetland system provided in this embodiment is used to facilitate water flow into the submerged flow wetland system by providing a water inlet pipe 61 at the water inlet.

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

[0065] By using the submerged flow wetland system provided in this embodiment, a water outlet weir 62 is provided at the water outlet, so that the purified water can flow out of the submerged flow wetland system.

[0066] In the above-mentioned submerged flow wetland system, under normal operating conditions, the incoming water is distributed to the first submerged flow wetland unit 1 near the water inlet through the water inlet pipe 61, and the treated water enters the next wetland unit through the bottom channel of the first partition wall 51 in turn. After being processed by multiple units, the water is finally discharged through the outlet weir 62.

[0067] In addition, the subsurface wetland system provided above has a set of flushing equipment installed inside each subsurface wetland unit 1. For example, the flushing equipment is selected as a flushing water pipe. In this case, the flushing water pipe can be arranged in a forward direction, that is, flushing is performed from the higher side of the subsurface wetland unit 1 toward the lower side. With such an arrangement, it can control the flow process of natural water in the wetland, help maintain the stability and naturalness of the internal ecosystem of the wetland, and achieve uniform flushing, avoiding the occurrence of excessive flushing or insufficient flushing in local areas. Of course, the flushing water pipe can also be arranged in the reverse direction, that is, flushing is performed from the lower side of the subsurface wetland unit 1 toward the higher side. With such an arrangement, it helps to achieve deep cleaning, effectively remove long-term accumulated blockages, help the wetland restore its due processing capacity, and help the water flow smoothly through the processing area inside the wetland, thereby improving the processing efficiency of the wetland. At the same time, it can also protect the internal ecosystem and processing facilities of the wetland, thereby extending the service life of the wetland.

[0068] In a second aspect, the present application also provides a method for alleviating wetland blockage, which is applied to the subsurface flow wetland system of the first aspect.

[0069] The method for alleviating wetland blockage is combined with a preset water level warning line of the monitoring section of each subsurface flow wetland unit 1, and the real-time water level is monitored by the water level monitoring component 4.

[0070] Specifically, the approach to mitigating wetland congestion includes the stages of preparation, identification, treatment, and restoration.

[0071] Among them, preparation: preset water level threshold; identification: each water level monitoring component 4 monitors the water level of the submerged wetland unit 1 in real time; processing: when the water level measured by any water level monitoring component 4 exceeds the threshold, open the conducting pipe 2 between the submerged wetland unit 1 and the downstream submerged wetland unit 1, so that the submerged wetland unit 1 can operate at a low water level; recovery: after the low water level operation of the submerged wetland unit 1 to be blocked ends, restore the flow of the submerged wetland unit 1 to a normal state.

[0072] It can be explained that the water level monitoring component 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 electric control 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 electric control valve 3 to change the throttling area of ​​the conducting pipe 2.

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

[0074] It can be explained that the preparation step also includes: increasing the porosity of the filler; and / or adding an aeration or backwashing device at the bottom of the filler.

[0075] By using the method for alleviating wetland blockage provided by this embodiment, the porosity of the filler is increased before the preparation step, the residence time of sewage in the wetland is prolonged, and the microorganisms, plants and other organisms in the wetland are more fully in contact with the sewage, thereby more effectively degrading and removing pollutants; at the same time, it helps to improve the water flow distribution inside each submerged wetland unit 1, making the water flow more uniform and reducing the occurrence of dead zones and short circuits; in addition, it is conducive to the circulation of air in each submerged wetland unit 1, and increasing the dissolved oxygen content inside the wetland. By adding aeration or backwashing equipment at the bottom of the filler, it is convenient to restore the capacity of the wetland and maintain the ecological health and sustainability of the wetland.

[0076] Specifically, the backwashing equipment includes a water pipe and a water pump. At this time, the water pipe is arranged on the downstream side of the submerged flow wetland unit, and its water outlet direction is arranged toward the upstream side. The water pump drives the water flow used for flushing to flow toward the upstream side.

[0077] It can be explained that the processing steps also include: turning over and drying, and replacing fillers.

[0078] By utilizing the method for alleviating wetland blockage provided in this embodiment, the compacted layer of wetland soil is easily broken by turning over and drying in the treatment step, thereby increasing the air permeability and water permeability of the soil, and thus improving the soil structure; at the same time, by promoting the activity of soil microorganisms, the decomposition of organic matter and the release of nutrients are accelerated, and the soil fertility is improved; in addition, the root growth environment of wetland plants can be improved, making the root system more developed, which is beneficial to the plant's absorption of water and nutrients, thereby promoting the growth and development of plants. By replacing new fillers, new biological communities can be introduced, and the treatment efficiency of the wetland can be restored, so that it can continue to effectively remove pollutants; at the same time, blockages can be removed and the wetland ecology can be optimized; in addition, by replacing new fillers, system failure or performance degradation caused by filler saturation or blockage can be avoided, thereby extending the service life of the wetland.

[0079] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A subsurface wetland system, characterized in that: include: At least two groups of submerged flow wetland units (1) arranged in series, the at least two groups of submerged flow wetland units (1) arranged in series are arranged at intervals between a wetland water inlet and a wetland water outlet along the flow direction of the water flow, and two adjacent groups of submerged flow wetland units (1) are connected via a conducting pipe (2); An electrically controlled valve (3), wherein any one of the conducting pipes (2) is provided with an electrically controlled valve (3); Wherein, at least one water level monitoring component (4) is provided in any submerged wetland unit (1), and any of the water level monitoring components (4) is electrically connected to a control terminal. The water level monitoring component (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 electric control valve (3) is electrically connected to the control terminal, and the control terminal is used to transmit the opening signal and control the opening degree of the valve core of the electric control valve (3) to change the throttling area of ​​the conducting pipe (2).

2. The subsurface wetland system according to claim 1, characterized in that: A transition section is provided between two adjacent groups of submerged flow wetland units (1) in the horizontal direction, and the transition section connects the two adjacent groups of submerged flow wetland units (1).

3. The subsurface wetland system according to claim 2, characterized in that: Each transition section comprises a first partition wall (51) and a second partition wall (52), wherein 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 submerged flow wetland unit, and the other is arranged close to the downward submerged flow wetland unit; There is a gap between the bottom of the partition wall close to the upward submerged flow wetland unit and the bottom of the upward submerged flow wetland unit, and the top of the partition wall close to the upward submerged flow wetland unit is higher than the top of the partition wall close to the downward submerged flow wetland unit.

4. The subsurface wetland system according to claim 1, characterized in that: Also includes: A filler layer, wherein each group of subsurface flow wetland units (1) is filled with a filler layer; A monitoring pipe, wherein each group of submerged flow wetland units (1) is provided with a monitoring pipe, wherein the monitoring pipe is inserted into the packing layer in a vertical direction, and the monitoring pipe is provided with a plurality of water inlet holes, wherein the plurality of water inlet holes are arranged along the axial direction and / or the circumferential direction thereof; Wherein, at least one water level monitoring component (4) is installed in any of the monitoring pipe components.

5. The subsurface flow wetland system according to any one of claims 1 to 4, characterized in that: Two adjacent groups of subsurface flow wetland units (1) are provided with a height difference in the vertical direction.

6. The subsurface flow wetland system according to any one of claims 1 to 4, characterized in that: A water inlet pipe (61) is provided at the water inlet of the wetland.

7. The subsurface flow wetland system according to any one of claims 1 to 4, characterized in that: A water outlet weir (62) is provided at the water outlet of the wetland.

8. A method for alleviating wetland blockage, applied to the submerged flow wetland system according to any one of claims 1 to 7, characterized in that: The method for alleviating wetland blockage comprises the following steps: Preparation: preset water level threshold; Identification: Each water level monitoring component (4) monitors the water level of the subsurface wetland unit (1) in real time; Processing: When the water level measured by any water level monitoring component (4) exceeds a threshold value, the conducting pipe component (2) between the submerged flow wetland unit (1) and its downstream submerged flow wetland unit (1) is opened, so that the submerged flow wetland unit (1) operates at a low water level; Restoration: After the low water level operation of the submerged flow wetland unit (1) to be blocked ends, the flow of the submerged flow wetland unit (1) is restored to a normal state.

9. The method for alleviating wetland blockage according to claim 8, characterized in that: The preparation step also includes: increasing the porosity of the filler; and / or adding an aeration or backwashing device at the bottom of the filler.

10. The method for alleviating wetland blockage according to claim 8, characterized in that: The processing steps also include: Turn over and dry, and replace fillers.

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