Water regulating pond system for reoxygenation, anti-clogging and / or anti-freezing of subsurface constructed wetlands

Abstract

The present invention provides a water regulating tank system for reoxygenation, anti-blocking and / or anti-freezing of submerged flow artificial wetlands. The system has low construction cost, does not require additional energy consumption and power, and is simple to manage and maintain. Based on the water regulating tank system provided by the present invention, reoxygenation, anti-blocking and / or anti-freezing operations can be conveniently achieved, which is beneficial to improving the purification function of submerged flow artificial wetlands, extending the life of wetlands, and ensuring that submerged flow wetlands can operate all year round in cold areas. The water regulating tank system provided by the present invention is arranged between the upper submerged flow wetland unit and the lower submerged flow wetland unit of the submerged flow artificial wetland system; the water regulating tank system includes a water regulating tank, a water regulating tank straight pipe with a valve, a connecting pipe with a valve, and an inlet movable bend pipe and an outlet movable bend pipe arranged in the water regulating tank; the water regulating tank straight pipe includes a first water regulating tank straight pipe and a second water regulating tank straight pipe.

Description

Technical Field

[0001] The present invention belongs to the technical field of ecological and environmental engineering, and specifically relates to a water regulating pool system design and an operation method thereof for reoxygenation, blockage prevention and / or freezing prevention of subsurface artificial wetlands. Background Art

[0002] Constructed wetlands are artificially constructed systems consisting of artificial fillers or matrices (gravel, limestone, zeolite, ceramsite, slag, and coarse sand, etc.) and wetland plants growing on them. Sewage or slightly polluted water flows on the surface or under the surface of the wetland matrix, relying on a series of physical, chemical, and biological processes such as matrix filtration and adsorption, plant absorption, and microbial metabolic transformation to degrade pollutants (or nutrients) in the water. It is a matrix-plant-microorganism composite system that simulates the natural wetland system but strengthens the wetland purification function. Generally speaking, artificial wetlands are divided into two types: surface flow and subsurface flow. As for subsurface flow artificial wetlands, they can be divided into vertical flow and horizontal flow subsurface flow artificial wetlands according to the difference in water flow direction.

[0003] Regardless of the type of subsurface flow wetland, since water mainly flows inside the matrix filler layer, matrix blockage and internal anaerobic problems are the main limiting factors in the application of subsurface flow wetlands. In the actual operation process, the suspended matter in the water body can easily cause wetland blockage and water flow short-circuiting, which in turn affects the wetland purification efficiency. At present, in domestic and foreign research or practice, the main way to deal with the problem of matrix blockage in subsurface flow wetlands is to reduce the content of suspended matter in the water as much as possible through pretreatment, restore internal permeability through intermittent operation, and regularly replace the matrix fillers in the blocked area. In general, there are many countermeasures, and the effects are uneven. In addition, there are shortcomings such as increased costs, increased wetland area, and damage to the maturity of the wetland microecological environment. The degradation process of organic matter in the water inside the wetland will consume a large amount of oxygen inside the wetland, but the subsurface flow wetland limits the reoxygenation effect inside the matrix due to its structure, which easily leads to long-term anaerobic conditions inside the matrix, thereby affecting the water purification efficiency, especially the nitrification efficiency, resulting in reduced denitrification efficiency. At present, artificial wetlands are mainly oxygenated by bottom or middle aeration and intermittent operation. Aeration requires additional power system, which increases additional costs. At the same time, since the openings of aeration pipes are easily clogged, the aeration efficiency will also be affected. Intermittent operation will increase the wetland area exponentially.

[0004] In summary, organic pollutants and their metabolites are the main causes of clogging and anaerobicity in artificial wetlands. The inorganic suspended particles and large organic solids in the influent can be solved through simple pretreatment measures (including screens, sedimentation, flocculation, etc.), but the clogging and anaerobic problems caused by dissolved organic matter and microbial metabolites accumulated in the matrix during operation are still the key limiting factors affecting wetland operation and purification efficiency.

[0005] In addition, although artificial wetlands are artificially enhanced natural wetland systems, their application in cold regions is still limited by low temperatures and freezing periods, and their purification capacity and efficiency are greatly reduced, and they cannot even operate normally during freezing periods. Although Chinese patent ZL2012201166788.9 discloses "a double-layer subsurface artificial wetland system for sewage treatment in small and medium-sized towns in cold regions", it can achieve alternating operation in winter and warm seasons mainly by increasing the depth of the matrix, the double-layer matrix filler layer, and the upper and lower double-layer water distribution design, but the system has a large change in the unit structure of conventional subsurface wetlands, especially the lack of reoxygenation, anti-blocking and dredging functions, and cannot solve the matrix blockage and anaerobic problems inside the matrix caused by the continuous operation of the wetland, which also causes the effluent of the system to only meet the Class B standard of GB18918-2002. Through research, the currently disclosed Chinese patent technologies for artificial wetlands cannot meet the need to solve multiple bottleneck problems such as reoxygenation, dredging, anti-blocking, water level regulation and antifreeze through simple optimization of the wetland system structure without any additional energy consumption and power. Summary of the invention

[0006] In view of this, the present invention provides a water regulating tank system and an operation method thereof which have low construction cost, do not require additional energy consumption and power, and are simple to manage and maintain. Based on the water regulating tank system provided by the present invention, operations such as reoxygenation, anti-blocking and / or anti-freezing can be conveniently implemented, which is beneficial to improving the purification function of the subsurface flow artificial wetland, extending the life of the wetland, and ensuring that the subsurface flow wetland can operate all year round in cold areas.

[0007] To achieve the purpose, the present invention provides the following technical solutions:

[0008] The present invention provides a water regulating pool system for reoxygenation, blocking prevention and / or freezing prevention of a submerged flow artificial wetland, wherein the water regulating pool system is arranged between an upper submerged flow wetland unit and a lower submerged flow wetland unit of a submerged flow artificial wetland system;

[0009] The water regulating tank system includes a water regulating tank, a water regulating tank straight pipe with a valve, a connecting pipe with a valve, and an inlet movable elbow pipe and an outlet movable elbow pipe arranged in the water regulating tank; the water regulating tank straight pipe includes a first water regulating tank straight pipe and a second water regulating tank straight pipe; a water regulating tank water inlet is provided at the lower part of the upstream wall of the water regulating tank, and the first water regulating tank straight pipe is installed on the water regulating tank water inlet; a lower water regulating tank water outlet is provided at the lower part of the downstream wall of the water regulating tank, and the second water regulating tank straight pipe is installed on the lower water regulating tank water outlet;

[0010] A water distribution pipe is provided in the upstream area of ​​the upper submerged flow wetland unit, and a water collecting pipe is installed in the downstream area of ​​the upper submerged flow wetland unit; the water regulating tank is connected to the lower part of the downstream wall of the upper submerged flow wetland unit through the first water regulating tank straight pipe; the water inlet end of the first water regulating tank straight pipe is connected to the water collecting pipe of the upper submerged flow wetland unit, the water outlet end of the first water regulating tank straight pipe is movably connected to the water inlet movable bend pipe, and the water inlet movable bend pipe can rotate between a horizontal position and a vertical position relative to the first water regulating tank straight pipe;

[0011] A water distribution pipe is installed in the upstream area of ​​the lower submerged flow wetland unit, and the water regulating tank is connected to the lower submerged flow wetland unit through the second water regulating tank straight pipe; the water inlet end of the second water regulating tank straight pipe is movably connected to the water outlet movable bend pipe, and the water outlet movable bend pipe can rotate between a horizontal position and a vertical position relative to the second water regulating tank straight pipe; the water outlet end of the second water regulating tank straight pipe is connected to the water distribution pipe in the lower submerged flow wetland unit; and a water collecting pipe is provided in the downstream area of ​​the lower submerged flow wetland unit.

[0012] In some embodiments, when the water inlet movable bend pipe is rotated to a vertical position, the height of the water inlet movable bend pipe does not exceed the highest water level of the upper submerged flow wetland unit;

[0013] The height of the water inlet movable bend pipe when it is rotated to a vertical position is 10-30 cm higher than the height of the water outlet movable bend pipe when it is rotated to a vertical position.

[0014] In some embodiments, a water diversion cap is installed at the water outlet end of the water inlet movable elbow; and a filter cap is installed at the water inlet end of the water outlet movable elbow.

[0015] In some embodiments, a cover plate is provided on the top of the water regulating tank.

[0016] In some embodiments, the distance between the water inlet of the water regulating pool and the bottom of the downstream area of ​​the upper submerged flow wetland unit is 10-30 cm;

[0017] The distance between the water outlet of the lower water regulating pool and the bottom of the lower submerged flow wetland unit is 10-50 cm.

[0018] In some embodiments, the water regulating tank straight pipe further comprises a third water regulating tank straight pipe;

[0019] An upper water regulating pool outlet connected to the lower submerged flow wetland unit is provided on the upper part of the downstream wall of the water regulating pool, the third water regulating pool straight pipe is installed on the upper water regulating pool outlet, and the third water regulating pool straight pipe is connected to the water distribution pipe in the lower submerged flow wetland unit;

[0020] The outlet of the upper water regulating tank is flush with the upper surface of the substrate of the lower submerged flow wetland unit, and when the water inlet movable bend pipe is rotated to a vertical position, the position of the outlet of the upper water regulating tank is 10-20 cm lower than the outlet end of the water inlet movable bend pipe.

[0021] The water distribution pipe of the upper submerged flow wetland unit is installed at the upper part or lower part of the upstream area of ​​the upper submerged flow wetland unit, and the water collection pipe of the upper submerged flow wetland unit is installed at the lower part or upper part of the downstream area in the upper submerged flow wetland unit accordingly;

[0022] The water distribution pipe of the lower submerged flow wetland unit is installed at the upper or lower part of the upstream area of ​​the lower submerged flow wetland unit, and the water collection pipe of the lower submerged flow wetland unit is correspondingly installed at the lower or upper part of the downstream area in the lower submerged flow wetland unit.

[0023] In some embodiments, the water regulating tank system is connected to the reflux system via the connecting pipe;

[0024] In some embodiments, the water regulating tank system is connected to the external discharge system through the connecting pipe.

[0025] In some embodiments, the water regulating tank system is connected to the backwashing system through the connecting pipe.

[0026] The connecting pipe is located at the lower part of the water regulating tank, and a plurality of water inlet holes are opened on the connecting pipe. Preferably, the connecting pipe is 5-10 cm away from the bottom of the water regulating tank.

[0027] The present invention also provides a subsurface artificial wetland system, which includes two or more subsurface wetland units in an upstream and downstream relationship from upstream to downstream, and the above-mentioned water regulating pool system is respectively arranged between the upper subsurface wetland unit and the lower subsurface wetland unit in every two adjacent subsurface wetland units;

[0028] One or more water regulating pool systems are arranged at intervals between the upper submerged flow wetland unit and the lower submerged flow wetland unit; adjacent water regulating pool systems are connected to each other through the connecting pipes;

[0029] The upper submerged flow wetland unit and the lower submerged flow wetland unit are respectively vertical flow type or horizontal flow type artificial wetlands, and the substrate depth of the upper submerged flow wetland unit and the lower submerged flow wetland unit is above 0.6m.

[0030] The present invention also provides an operation method of the water regulating pool system described above. It is characterized in that:

[0031] (A) When aeration and reoxygenation are required, the operation method comprises the following steps:

[0032] By rotating the water inlet movable bend pipe and / or rotating the water outlet movable bend pipe so that the height of the water outlet end of the water inlet movable bend pipe is higher than the water level of the water regulating pool to form a waterfall, the water from the upper submerged flow wetland unit flows out through the water outlet end of the water inlet movable bend pipe to form a fountain for aeration and reoxygenation. Preferably, a water diversion cap is installed at the water outlet end of the water inlet movable bend pipe;

[0033] (B) When anti-blocking and dredging is required, the operation method includes the following steps:

[0034] B1) rotating the water inlet movable elbow to a vertical position and / or closing the valve of the first water regulating tank straight pipe, so that the upper submerged flow wetland unit reaches its highest water level; at the same time, rotating the water outlet movable elbow to a horizontal position, and fully opening the valve of the second water regulating tank straight pipe, so that the water in the water regulating tank is discharged to the lowest water level;

[0035] B2) then closing the valve of the second water regulating tank straight pipe, rotating the water inlet movable elbow to a horizontal position, and fully opening the valve of the first water regulating tank straight pipe, so that the water in the upper submerged flow wetland unit is accelerated to flow to the water regulating tank under high water pressure, thereby flushing and desilting the upper submerged flow wetland unit;

[0036] B3) rotating the outlet movable bend pipe, preferably rotating the outlet movable bend pipe to a vertical position, and opening the valve of the second water regulating tank straight pipe, so that the water flowing from the water regulating tank to the lower submerged flow wetland unit is water from the upper layer of the water regulating tank; or, an upper water regulating tank outlet connected to the lower submerged flow wetland unit is provided on the upper part of the downstream wall of the water regulating tank, and the water in the water regulating tank flows to the lower submerged flow wetland unit through the upper water regulating tank outlet;

[0037] (C) When antifreeze is required, the operation method comprises the following steps:

[0038] Before entering the freezing period, the upper submerged flow wetland unit reaches its highest water level by rotating the water inlet movable elbow to a vertical position and / or closing the valve of the first water regulating tank straight pipe, and a frozen layer is formed in the upper submerged flow wetland unit after entering the freezing period;

[0039] Then, the water inlet movable elbow is rotated to form an air isolation layer of 0.5-15 cm between the water level in the upper submerged flow wetland unit and the frozen layer; if the valve of the first water regulating tank straight pipe is closed during the process of forming the frozen layer, the valve of the first water regulating tank straight pipe is opened at the same time during the step of forming the air isolation layer;

[0040] A cover plate is arranged on the top of the water regulating tank, and a heat-insulating layer is covered on the top of the cover plate to prevent the water in the water regulating tank from freezing.

[0041] In some embodiments, the step (C) further comprises the following steps:

[0042] Before the frozen layer is formed, a support structure is provided on the substrate surface of the upper subsurface flow wetland unit to support the frozen layer;

[0043] In some embodiments, the surface of the frozen layer is covered with a thermal insulation material.

[0044] (D) When it is necessary to drain the water in the subsurface wetland unit, the operation method comprises the following steps:

[0045] When the water collecting pipe of the upper submerged flow wetland unit is installed at the lower part of the downstream area, the water in the upper submerged flow wetland unit is discharged into the water regulating pool through the water inlet of the water regulating pool, and then discharged into the lower submerged flow wetland unit from the water regulating pool, or the water discharged into the water regulating pool is discharged outward through the connecting pipe installed at the lower part of the water regulating pool, thereby emptying the water in the upper submerged flow wetland unit;

[0046] When the water collecting pipes of the upper submerged flow wetland unit or the lower submerged flow wetland unit are installed at the upper part of the respective downstream areas, the respective water bodies are emptied by installing drain pipes in the upper submerged flow wetland unit or the lower submerged flow wetland unit, respectively.

[0047] The technical solution provided by the present invention has the following beneficial effects:

[0048] The present invention discloses a water regulating pool system for reoxygenation, anti-blocking and anti-freezing of subsurface artificial wetlands. Based on the water regulating pool system, by regulating a specific operation mode, the limitations of the subsurface wetland matrix blockage and internal anaerobicity can be simultaneously broken through, and the limitations of artificial wetlands subject to low temperature and freezing can be broken through, so as to ensure its normal operation in cold areas. The water regulating pool system has multiple functions such as water outlet and water inlet allocation for upper and lower wetland units, silt removal and anti-blocking for upper wetland units, water supply reoxygenation, water level regulation and wetland emptying. The present invention also provides an operation method for reoxygenation, anti-blocking, silt removal and anti-freezing using the water regulating pool system. The structural design and operation method of the water regulating pool system provided by the present invention can effectively solve the problems of blockage and anaerobicity in subsurface wetlands. At the same time, the water level regulation function of the water regulating pool can effectively solve the problem of winter anti-freezing in cold areas of the wetland system. The present invention does not require additional energy consumption, has a simple structure, low cost, high efficiency, easy maintenance and a wide range of applications.

[0049] (1) The technical solution of the present invention only adds a water regulating pool system between conventional wetland units, which makes little change to the engineering structure of the conventional subsurface artificial wetland system and has a small cost increase;

[0050] (2) The principle of the technical solution of the present invention is mainly to achieve multiple functions by regulating the water level difference between the upper and lower wetlands through the natural flow of water bodies, without the need to increase energy consumption and power systems;

[0051] (3) The technical solution of the present invention has a dual anti-blocking strategy for the upper and lower units, and in particular, the dredging effect in the wetland unit matrix can be achieved without replacing the wetland matrix, effectively solving the problem of wetland matrix blockage caused by continuous operation;

[0052] (4) The technical solution of the present invention realizes direct reoxygenation of the water body through the unpowered gravity design, avoiding the increase of additional energy consumption and cost caused by aeration inside the wetland matrix;

[0053] (5) The technical solution of the present invention adjusts the water level in the wetland unit through the water regulating pool system, and realizes multiple measures such as ice cover, air isolation and cover isolation during winter operation to keep the wetland warm. At the same time, the water regulating pool system can be reoxygenated, effectively solving the problem of antifreeze and aggravation of anaerobic water in the internal water body of the subsurface flow wetland in cold areas after covering;

[0054] (6) The technical solution of the present invention connects multiple water regulating pools through connecting pipes. The pipes can be connected to the return system or the external discharge system as needed. The water can be returned to the water distribution system at the front end of the wetland for secondary purification according to whether the water quality index meets the standard. When the wetland unit or the water regulating pool has a lot of sediment due to long-term sedimentation, it can be discharged through the external discharge system, which can improve the purification efficiency of the wetland and extend the service life of the wetland;

[0055] To sum up, the water regulating pool system technical solution provided by the present invention has a simple structure, low cost, good effect and high efficiency. It can realize multiple functions such as reoxygenation, anti-blocking, silt removal, water level regulation and / or anti-freezing through simple operation and maintenance, and has great promotion and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 A schematic plan view of a water regulating pool system in one embodiment;

[0057] Figure 2 A schematic elevation view of a water regulating pool system in one embodiment;

[0058] Figure 3 This is a schematic diagram of the internal structure of the water regulating pool;

[0059] Figure 4 This is the actual effect diagram of the water transfer pool;

[0060] Figure 5 It is a partial schematic diagram of a water collecting pipe or a water distribution pipe;

[0061] Figure 6 for Figure 5A side view schematic diagram of

[0062] Description of reference numerals:

[0063] 1. Upper subsurface wetland unit; 2. Lower subsurface wetland unit; 3. Wetland filler; 4. Wall; 5. Water regulating tank; 6. Water collecting pipe; 6-1. Water collecting pipe installed on the upper part; 6-2. Water collecting pipe installed on the lower part; 7. Water inlet of water regulating tank; 8. Water inlet movable elbow pipe; 9. Water distribution pipe; 9-1. Upper water distribution pipe; 9-2. Lower water distribution pipe; 10. Water outlet of upper water regulating tank; 11. Water outlet movable elbow pipe; 12. Valve; 13. Connecting pipe; 14. Water outlet of lower water regulating tank; 15. Cover plate; 16. Water distribution cap; 17. Filter cap; 18. Water collecting hole / water distribution hole; 19. Straight pipe of the first water regulating tank; 20. Straight pipe of the second water regulating tank; 21. Straight pipe of the third water regulating tank; 22. Downstream wall; 23. Upstream wall. DETAILED DESCRIPTION

[0064] The present invention is further described in detail below in conjunction with specific implementation modes, but the application scope of the present invention is not limited thereto.

[0065] Positional terms such as upper, lower, top, bottom, etc. mentioned or may be mentioned in this article are defined relative to the structures shown in the drawings. They are relative concepts and may change accordingly according to their different positions and different usage states.

[0066] Anything not specifically described herein can be known or understood by those skilled in the art based on their conventional techniques and common knowledge.

[0067] See also Figure 1-4 The present invention provides a water regulating pool system for reoxygenation, anti-blocking and / or anti-freezing of a submerged flow artificial wetland. The water regulating pool system is arranged between an upper submerged flow wetland unit 1 and a lower submerged flow wetland unit 2 of a submerged flow artificial wetland system.

[0068] The upper submerged wetland unit 1 and the lower submerged wetland unit 2 are in an upstream and downstream relationship in the direction of water flow. The submerged wetland structure of the two can adopt the submerged artificial wetland structure well known in the art, which can be a vertical flow type or a horizontal flow type, or a composite submerged wetland of vertical flow and horizontal flow. The substrate depth in the wetland unit is not less than 0.6m. The submerged wetland unit mentioned can be various types of submerged artificial wetlands used for sewage treatment, deep purification of sewage plant tail water, purification and treatment of micro-polluted water, etc. Specifically, there is a wall 4 outside the wetland unit, which can be a hardened structure such as brickwork, concrete or stonework. The main improvement of the present invention is that a water regulating pool system is cleverly set between the upper submerged wetland unit 1 and the lower submerged wetland unit 2. On the basis of not making substantial modifications to the existing submerged wetland units, the construction cost is low and no additional energy consumption and power are required to achieve reoxygenation, anti-blocking and / or anti-freezing operations. Anything not specifically described herein is understood or known to those skilled in the art based on the prior art or common knowledge, and will not be described in detail.

[0069] The water regulating tank system of the present invention specifically includes a water regulating tank 5, a plurality of water regulating tank straight pipes, an inlet movable bend pipe 8, an outlet movable bend pipe 11, and a connecting pipe 13 with a valve. Each of the water regulating tank straight pipes is provided with a valve 12, and the inlet movable bend pipe 8 and the outlet movable bend pipe 11 are both arranged in the water regulating tank 5. The water regulating tank straight pipes specifically include a first water regulating tank straight pipe 19, a second water regulating tank straight pipe 20, and a third water regulating tank straight pipe 21. The "first", "second", and "third" are mainly for the convenience of distinguishing the description, and are not intended to limit the specific quantity or order. The water regulating tank 5 is a tank body arranged between the upper submerged flow wetland unit 1 and the lower submerged flow wetland unit 2, and is mainly used to collect the outlet water of the upper submerged flow wetland unit 1 and distribute water to the lower submerged flow wetland unit 2, such as a mortar-laid tank body.

[0070] A water distribution pipe (not shown) is provided in the upstream area of ​​the upper submerged flow wetland unit 1, through which water is distributed to the upper submerged flow wetland unit. A water collecting pipe 6 is installed in the downstream area of ​​the upper submerged flow wetland unit 1. As is well known in the art, the "upstream" and "downstream" mentioned herein are relative to the direction of water flow. The upper submerged flow wetland unit 1 can selectively adopt a water distribution method of top-in and bottom-out or bottom-in and top-out, and correspondingly adopt bottom water collection or top water collection. The technicians in this field can choose according to their needs; specifically, for example, when the water distribution method of the upper submerged flow wetland unit 1 is top-in and bottom-out, that is, the water distribution pipe is arranged at the upper part of the upstream area of ​​the upper submerged flow wetland unit 1, the water collection pipe 6-2 can be installed specifically at the lower part of the downstream area in the upper submerged flow wetland unit 1; when the water distribution method of the upstream submerged flow wetland unit 1 is bottom-in and top-out, that is, the water distribution pipe is arranged at the lower part of the upstream area of ​​the upper submerged flow wetland unit 1, the water collection pipe 6-1 can be installed specifically at the upper part of the downstream area in the upper submerged flow wetland unit 1, and through the vertical pipeline ( Figure 2 The water collecting pipe 6-2 is connected to the water collecting pipe 6-1, or the water collecting pipe 6-1 is directly connected to the first water regulating tank straight pipe 19 on the water inlet 7 of the water regulating tank through a vertical pipe. Figure 5 The water collecting pipe 6 is provided with a water collecting hole 18, and similarly, the water distributing pipe is provided with a water distributing hole. A water inlet 7 (equivalent to the water outlet of the upper submerged flow wetland unit) is provided at the lower part of the upstream wall 22 of the water regulating pool 5 (equivalent to the downstream wall of the upper submerged flow wetland unit 1), which can be a circular hole; a first water regulating pool straight pipe 19 is installed on the water inlet 7 of the water regulating pool, and the upper submerged flow wetland unit 1 and the water regulating pool 5 are connected through the first water regulating pool straight pipe 19. The water inlet end of the first water regulating tank straight pipe 19 is connected to the water collecting pipe 6, and the water outlet end of the first water regulating tank straight pipe 19 is movably connected to the water inlet movable bend pipe 8, so that the water inlet movable bend pipe 8 can rotate relative to the first water regulating tank straight pipe 19. Specifically, the water inlet movable bend pipe 8 can rotate freely between the horizontal position and the vertical position, that is, the water inlet movable bend pipe 8 can rotate freely within the range of 0-90° with the horizontal plane, so as to flexibly adjust the height of the water outlet end of the water inlet movable bend pipe 8, and then adjust the water inlet height, so as to realize the water level regulation and aeration function of the upper submerged flow wetland unit 1, and realize the water body reoxygenation and sedimentation effect. Specifically, when the water distribution direction of the upper submerged flow wetland unit 1 is bottom-in and top-out, the water inlet end of the first water regulating tank straight pipe 19 is connected to the water collecting pipe 6-1 located at the upper part of the downstream area of ​​the upper water flow wetland unit; when the water distribution direction of the upper submerged flow wetland unit 1 is top-in and bottom-out, the water inlet end of the first water regulating tank straight pipe 19 is connected to the water collecting pipe 6-2 located at the lower part of the downstream area of ​​the upper water flow wetland unit.

[0071] A water distribution pipe 9 is installed in the upstream area of ​​the lower submerged flow wetland unit 2, and a water collecting pipe (shown in the figure) is installed in the downstream area. Similar to the water distribution pipe and water collecting pipe of the upper submerged flow wetland unit 1, the two can be selectively configured to allow water to enter from the bottom and exit from the top or enter from the top and exit from the bottom in the lower submerged flow wetland unit 2, that is, the water distribution pipe 9 of the lower submerged flow wetland unit is installed at the upper or lower part of the upstream area of ​​the lower submerged flow wetland unit 2 (that is, the upper water distribution pipe 9-1 or the lower water distribution pipe 9-2), and the water collecting pipe of the lower submerged flow wetland unit is correspondingly installed at the lower or upper part of the downstream area of ​​the lower submerged flow wetland unit. Those skilled in the art can make a selection according to their needs. A water collecting hole is opened on the water distribution pipe 9 in the lower submerged flow wetland unit 2, and a water distribution hole is opened on the water distribution pipe, such as Figure 5 As shown. A lower water regulating pool outlet 14, such as a circular hole, is provided at the lower part of the downstream wall 23 of the water regulating pool (equivalent to the upstream wall of the lower submerged flow wetland unit 2); a second water regulating pool straight pipe 20 is installed on the lower water regulating pool outlet 14, and the water regulating pool 5 and the lower submerged flow wetland unit 2 are connected through the second water regulating pool straight pipe 20. The water inlet end of the second water regulating pool straight pipe 20 is movably connected to the water outlet movable bend pipe 11, so that the water outlet movable bend pipe 11 can rotate relative to the second water regulating pool straight pipe 20. Specifically, the water outlet movable bend pipe 11 can rotate freely between the horizontal position and the vertical position, that is, the water outlet movable bend pipe 11 can rotate freely within the range of an angle of 0-90° with the horizontal plane, so as to flexibly adjust the height of the water inlet end of the water outlet movable bend pipe 11, that is, adjust the water distribution height of the lower water outlet 14. The outlet end of the second water regulating tank straight pipe 20 is connected to the water distribution pipe 9. According to the water distribution mode of the lower submerged flow wetland unit, the outlet end of the second water regulating tank straight pipe 20 is connected to the lower water distribution pipe 9-2 or the upper water distribution pipe 9-1 (when connected to the upper water distribution pipe 9-1, the connection can be achieved by setting a vertical pipe between the two), so as to distribute the water in the water regulating tank 5 to the lower submerged flow wetland unit 2. The water regulating tank outlet 14 opened at the lower part of the upstream wall of the lower submerged flow wetland unit and the water regulating tank outlet 10 opened at the upper part are equivalent to the water inlet of the lower submerged flow wetland unit.

[0072] The water distribution pipes or water collection pipes can be arranged in a single row or in multiple rows in parallel. As mentioned above, according to the water distribution method of top-in and bottom-out or bottom-in and top-out, the position can be changed up and down as needed.

[0073] More specifically, when the water inlet movable bend pipe 8 rotates to a vertical position, the height of the water inlet movable bend pipe 8 does not exceed the highest water level of the upper submerged flow wetland unit 1. The height of the water inlet movable bend pipe 8 when it rotates to a vertical position is 10-30 cm higher than the height of the water outlet movable bend pipe 11 when it rotates to a vertical position, for example, 10-20 cm. This height difference is preferred, which is conducive to obtaining a good aeration effect on the one hand, and avoids a large increase in cost due to excessive height difference on the other hand.

[0074] More specifically, the distance between the water inlet 7 of the water regulating pool and the bottom of the downstream area of ​​the upper submerged flow wetland unit 1 is 10-30 cm; the distance between the water outlet 14 of the lower water regulating pool and the bottom of the lower submerged flow wetland unit 2 is 10-50 cm.

[0075] In some embodiments, the upper part of the downstream wall 23 of the water regulating pool 5 (equivalent to the upstream wall of the lower submerged wetland unit 2) is provided with an upper water regulating pool outlet 10 connected to the lower submerged wetland unit 2, and the upper water regulating pool outlet 10 is installed with a third water regulating pool straight pipe 21, and the third water regulating pool straight pipe 21 is connected to the water distribution pipe 9. The upper water regulating pool outlet 10 is flush with the upper surface of the substrate of the lower submerged wetland unit 2, and when the water inlet movable bend 8 is rotated to a vertical position, the position of the upper water regulating pool outlet 10 is 10-20 cm lower than the height of the outlet end of the water inlet movable bend 8. The preferred height difference is conducive to obtaining a good aeration effect on the one hand, and on the other hand, avoiding a large increase in cost due to excessive height difference. Through this design, that is, the upper and lower double-layer water outlet design, the water regulating pool 5 can distribute water to the lower submerged wetland unit 2 through the upper water outlet and / or the lower water outlet as needed.

[0076] Preferably, a cover plate 15 is provided on the top of the water regulating tank 5 to facilitate antifreeze operation during the freezing period; the cover plate can be made of antiseptic wood, concrete, metal, etc.

[0077] Furthermore, a water diversion cap 16 is installed at the water outlet end of the water inlet movable elbow 8 to enhance the aeration and reoxygenation effect; a filter cap 17 is installed at the water inlet end of the water outlet movable elbow 11 to filter particulate matter.

[0078] The first water regulating tank straight pipe 19 is used to collect the outflow of the upper submerged flow wetland unit 1, and the valve on the straight pipe can be used to regulate the water inlet of the water regulating tank 5; the valves on the second water regulating tank straight pipe 20 and the third water regulating tank straight pipe 21 can be used to regulate the water inlet of the lower submerged flow wetland unit 2.

[0079] The present invention also provides a submerged artificial wetland system based on the water regulating pool system provided above, in which one or more water regulating pool systems arranged at intervals can be provided between the upper submerged wetland unit 1 and the lower submerged wetland unit 2; the number and volume of the water regulating pool 5 can be determined according to the width of the wetland unit, the hydraulic load, and the position of the water outlet of the upper wetland unit and the water inlet of the lower wetland unit. Adjacent water regulating pool systems can be interconnected through a connecting pipe 13, and the connecting pipe 13 is located at the lower part of the water regulating pool 5. Preferably, the distance between the connecting pipe 13 and the bottom of the water regulating pool 5 can be 5-10cm. Specifically, a plurality of water inlet holes are provided in the connecting pipe 13 (when the water in the water regulating pool needs to be discharged outward, the collection efficiency of the water inside the water regulating pool is improved), and valves are reserved on both sides so as to connect the reflux system or the external discharge system or the backwash system as needed. When the width of the submerged wetland unit is less than 8m, only one water regulating pool system can be provided. Specifically, the volume of the water regulating pool 5 corresponding to each upper wetland unit can at least meet the requirement that the lower wetland unit does not overflow during normal water distribution. In some embodiments, the bottom elevation of the water regulating pool is equal to the bottom elevation of the downstream outlet of the upper wetland unit, and the inside of the water regulating pool is treated with anti-seepage and cement mortar.

[0080] In some embodiments, the water regulating pool system can be connected to the return system through the connecting pipe 13 as needed; the water regulating pool system can be connected to the external discharge system through a pipe as needed. The return system means that when the effluent of the subsurface wetland unit does not meet the standard, the effluent is discharged into the return system through the connecting pipe and enters the water distribution system at the front end of the wetland for secondary treatment. The external discharge system means that when a lot of silt is deposited in the water regulating pool 5 due to long-term continuous operation, it can be connected to the external discharge system through a connecting pipe to discharge the silt and ensure the water inlet of the lower wetland unit.

[0081] The above-mentioned submerged flow artificial wetland system is not limited to one upper submerged flow wetland unit 1 and one lower submerged flow wetland unit 2, and may include multiple submerged flow wetland units with an upstream and downstream relationship from upstream to downstream in the entire submerged flow wetland system, wherein the water regulating pool system described in the present invention is respectively provided between the upper submerged flow wetland unit and the lower submerged flow wetland unit in every two adjacent submerged flow wetland units, that is, the water regulating pool system can be provided between the upper submerged flow wetland unit and the lower submerged flow wetland unit in the manner described in the present invention.

[0082] The main pipelines involved in the water regulating tank system of the present invention, such as the water regulating tank straight pipe, water distribution pipe, water collecting pipe, water inlet movable bend pipe 8 and water outlet movable bend pipe 11, etc. can be made of but not limited to UPVC pipes.

[0083] In the present invention, the water inlet movable bend pipe 8 and the water outlet movable bend pipe 11 can be straight pipes with openings at both ends, which can be connected to the corresponding straight pipes of the water regulating tank with valves through 90° elbows, or the water inlet movable bend pipe 8 and the water outlet movable bend pipe 11 can be 90° elbows with openings at both ends, which are directly connected to the corresponding straight pipes of the water regulating tank with valves.

[0084] The water regulating tank system provided by the present invention, when operating normally (for example, during operation in warm seasons), the water in the upper submerged flow wetland unit 1 enters the first water regulating tank straight pipe 19 through the water collecting pipe 6, and then flows into the water inlet movable bend pipe 8, flows out through the water outlet end of the water inlet movable bend pipe 8, and enters the water regulating tank 5; the water in the water regulating tank 5 enters the lower submerged flow wetland unit 2 through the second water regulating tank straight pipe 20 or the third water regulating tank straight pipe 21, wherein, if the water enters the lower submerged flow wetland unit 2 through the second water regulating tank straight pipe 20, the water in the water regulating tank 5 first enters the water outlet movable bend pipe 11 from the water inlet end of the water outlet movable bend pipe 11, and then flows into the lower submerged flow wetland unit 2 through the second water regulating tank straight pipe 20. During normal operation, the required water level requirements can be obtained according to the different needs of different stages of wetland operation (such as the early and mature stages of wetland operation) by rotating the water inlet movable bend 8, rotating the water outlet movable bend 11, and adjusting the valves of the water regulating tank straight pipes 19, 20, and 21, or a combination of multiple operations to maintain the construction of wetland plants and microbial systems.

[0085] The water regulating pool system of the present invention can very conveniently realize the functions of reoxygenation and aeration, anti-blocking and desilting, and / or anti-freezing. In the normal operation process, if these requirements are encountered, the above purposes can be achieved through different operation operations. This is described below.

[0086] (A) When aeration and reoxygenation are required, for example, according to the monitoring results of the dissolved oxygen concentration in the water during the operation of the wetland, when the dissolved oxygen concentration in the water is lower than 4 mg / L, the operation method of the water regulating pool system specifically includes the following steps:

[0087] By rotating the water inlet movable bend 8 and / or the water outlet movable bend 11, the height of the outlet end of the water inlet movable bend 8 and / or the water level in the water regulating pool 5 are adjusted, so that the outlet end of the water inlet movable bend 8 is higher than the water level of the water regulating pool 5 to form a waterfall drop, so that the water from the upper submerged flow wetland unit 1 forms a water fountain when flowing out through the outlet end of the water inlet movable bend 8, thereby performing aeration and reoxygenation, that is, unpowered aeration through the water level drop. In some specific embodiments, for example, the water inlet movable bend 8 is rotated to a vertical position to achieve the required drop, and the water is discharged through the second water regulating pool straight pipe 20. Specifically, according to different degrees of aeration needs, the angles of the water inlet movable bend 8 and the water outlet movable bend 11 can be adjusted to adjust different degrees of water level drop, achieve different degrees of aeration, and regulate the reoxygenation effect. During the operation of the wetland unit, the above-mentioned aeration operation can be performed regularly as needed. A water diversion cap 16 is installed at the water outlet end of the water inlet movable elbow 8 to enhance the aeration and reoxygenation effect.

[0088] (B) When anti-blocking and dredging are required, the operation method of the water regulating pool system specifically includes the following steps:

[0089] B1) rotating the water inlet movable elbow 8 to a vertical position and / or closing the valve of the first water regulating tank straight pipe 19, so that the upper submerged flow wetland unit 1 reaches its highest water level; at the same time, rotating the water outlet movable elbow 11 to a horizontal position, and fully opening the valve of the second water regulating tank straight pipe 20, so that the water in the water regulating tank 5 is discharged to the lowest water level;

[0090] B2) Then close the valve of the second water regulating pool straight pipe 20, rotate the water inlet movable elbow pipe 8 to the horizontal position, and fully open the valve of the first water regulating pool straight pipe 19. Due to the pressure formed by the high water level in the upper wetland unit, the water flow inside the upper wetland unit 1 is accelerated, so that the water in the upper submerged flow wetland unit 1 is accelerated to flow to the water regulating pool 5, so as to flush and desilt the upper submerged flow wetland unit 1. For example, in some embodiments, the water level is lowered to the height of the water inlet of the water regulating pool; in this way, the metabolites or aged biofilms formed in the pores and surface of the wetland matrix can be discharged from the wetland through the water flow to the greatest extent, thereby realizing the desilting of the upper wetland unit without digging the matrix;

[0091] B3) Then rotate the outlet movable bend pipe 11. Specifically, for example, the outlet movable bend pipe 11 can be rotated to a vertical position, and the valve of the second water regulating tank straight pipe 20 can be opened, so that the water flowing from the water regulating tank 5 to the lower submerged wetland unit 2 is water from the upper layer in the water regulating tank 5; or, the water in the water regulating tank flows to the lower submerged wetland unit 2 through the third water regulating tank straight pipe 21 installed on the upper water regulating tank outlet 10. Through such operation, the water distribution from the water regulating tank 5 to the lower submerged wetland unit 2 is the upper layer water, and some suspended particles in the water will precipitate during the retention of the water body in the water regulating tank 5, which can reduce the suspended particles from entering the lower wetland unit 2 to a certain extent, and reduce the risk of blockage of the lower wetland unit. Preferably, step B3) can be performed after the water in the water regulating tank is allowed to settle, so as to avoid particles from entering the lower submerged wetland unit 2 to a greater extent.

[0092] Regarding anti-blockage and dredging, it can be carried out regularly during normal operation, for example, once every 5-6 months.

[0093] In some embodiments, for the case where the upper submerged flow wetland unit has bottom-in and top-out, a drain pipe with a valve can be added to the lower part of the upper submerged flow wetland unit as needed, and the opening and closing of the valve can be adjusted as needed to achieve better anti-blocking and dredging effects.

[0094] (C) When antifreeze is required, such as when operating in winter or in cold areas, the operation method of the water regulating pool system specifically includes the following steps:

[0095] Before entering the freezing period, the upper submerged flow wetland unit 1 reaches its highest water level by rotating the water inlet movable elbow 8 to a vertical position and / or closing the valve of the first water regulating tank straight pipe 19, so that a frozen layer (or ice cap) is formed on the upper part of the upper submerged flow wetland unit 1 after entering the freezing period; specifically, for example, a frozen layer is formed inside the wetland by natural freezing during the freezing period in winter, and the thickness of the frozen layer is determined according to the thickness of the ice layer of the local still water body;

[0096] Then, by rotating the water inlet movable elbow 8, an air isolation layer of 0.5-15 cm is formed between the water level in the upper submerged flow wetland unit 1 and the frozen layer (that is, the distance between the frozen layer and the water level reaches 0.5-15 cm), that is, operation is adopted below the water level of the frozen layer; in this operation, if the valve of the first water regulating tank straight pipe 19 is closed during the formation of the frozen layer, then in the step of forming the air isolation layer, the valve of the first water regulating tank straight pipe 19 is opened at the same time.

[0097] A cover plate 15 is provided on the top of the water regulating tank 5 , and a heat-insulating layer is covered on the top of the cover plate to prevent the water in the water regulating tank 5 from freezing.

[0098] During the antifreeze process, the angles of the water inlet movable bend 8 and the water outlet movable bend 11 can also be adjusted, and the adjustment of the straight pipe valve of the water regulating tank can also be coordinated to ensure smooth water inlet to the lower-level submerged flow wetland unit 2 and aeration of the water inside the water regulating tank 5.

[0099] Specifically, when operating in winter, it is better to maintain low water level operation.

[0100] When the wetland unit area is large, before the formation of the frozen layer, that is, before freezing, a support structure can be set on the substrate surface of the upper subsurface flow wetland unit 1 to support the frozen layer, for example, one or more ice cover supports can be set on the substrate surface using bricks, stones, wooden piers, etc.; the water body below the air isolation layer can flow normally. Depending on the cold conditions in the region, the surface of the frozen layer can be covered with harvested wetland plants or other warming materials.

[0101] After performing the above antifreeze operations, the remaining operations can be carried out as usual.

[0102] (D) When it is necessary to drain the water of the subsurface wetland unit for intermittent operation, the operation method comprises the following steps:

[0103] When the water collecting pipe of the upper submerged flow wetland unit is installed at the lower part of the downstream area (i.e., lower water collecting), the water in the upper submerged flow wetland unit is discharged into the water regulating tank through the water inlet of the water regulating tank. Specifically, the valve of the straight pipe of the first water regulating tank can be opened, and the water inlet movable elbow pipe can be rotated to a horizontal position; the water discharged into the water regulating tank is discharged into the lower submerged flow wetland unit or the water discharged into the water regulating tank is discharged outward through the connecting pipe installed at the lower part of the water regulating tank, thereby emptying the water in the upper submerged flow wetland unit;

[0104] When the water collection pipe of the upper submerged flow wetland unit or the lower submerged flow wetland unit is installed at the upper part of the respective downstream area (i.e., upper water collection), the respective water bodies can be emptied by installing emptying pipes in the upper submerged flow wetland unit or the lower submerged flow wetland unit respectively;

[0105] Of course, depending on the specific situation, for example, for the last level of subsurface wetland unit downstream, whether it is the upper water collection or the lower water collection, the water inside it can be directly drained by installing a drain pipe.

[0106] In the above four situations (A)-(D), during the specific operation process, the valves of the water inlet / outlet movable elbow pipes and the water tank straight pipes / connecting pipes in the water regulating tank can be adjusted according to the control needs.

[0107] The water regulating tank system of the present invention, wherein the regulation of each water regulating tank straight pipe (such as the first water regulating tank straight pipe, the second water regulating tank straight pipe and the third water regulating tank straight pipe) and the valves of the connecting pipes, the angle adjustment of the water inlet movable bend pipe, and the angle adjustment of the water outlet movable bend pipe can be manually regulated or automatically controlled. For the automatic control method, it can be implemented by conventional automatic control methods well known in the art, which will not be elaborated herein.

[0108] Example 1

[0109] This embodiment is a water regulating pool system for reoxygenation, anti-blocking and / or anti-freezing of subsurface artificial wetlands. Figure 1-6 The structure of the water regulating pool system of this embodiment is as described above. The upper submerged wetland unit 1 and the lower submerged wetland unit 2 are 10m long, 4m wide, and the average depth of the filling is 1.2m; the water regulating pool is 4m long, 0.8m wide, and 1.5m deep. The main pipelines of the water regulating pool system (such as water distribution pipes, water collection pipes, water inlet movable bend pipes 8 and water outlet movable bend pipes 11, etc.) are made of UPVC pipes with a diameter of 12cm, and the opening diameters of the water collection pipes and water distribution pipes are 1cm ( Figure 5 There are two water inlets 7 in the water regulating tank, two water outlets 14 in the lower water regulating tank, and two water outlets 10 in the upper water regulating tank. The elbow ends of the water inlet movable bend pipe 8 and the water outlet movable bend pipe 11 are respectively nested and connected with the first water regulating tank straight pipe 19 and the second water regulating tank straight pipe 20, and the movable bend pipe can rotate freely between the horizontal position and the vertical position. The water outlet end of the water inlet movable bend pipe 8 is installed with a water divider 16, and the water inlet end of the water outlet movable bend pipe 11 is installed with a filter cap 17. The water inlet 7 of the water regulating pool is 20 cm away from the bottom of the downstream area of ​​the upper submerged flow wetland unit 1, and the water outlet 20 of the lower water regulating pool is 10 cm away from the bottom of the lower submerged flow wetland unit 2; when the water inlet movable elbow 8 is rotated to a vertical position, and the water outlet movable elbow 11 is rotated to a vertical position, the water outlet end of the water inlet movable elbow 8 is 30 cm higher than the water inlet end of the water outlet movable elbow 11, and the water outlet end of the water inlet movable elbow 8 is 20 cm higher than the water outlet 21 of the upper water regulating pool ( Figure 3 During the plant growth season, floating plants such as water hyacinth are planted inside the water transfer pool 5 to increase the purification effect ( Figure 4 In this embodiment, the outer wall 4 of the wetland unit is a brick-concrete structure, and the cover of the water regulating pool 5 is a 10 cm thick wooden board, which is not covered during the non-freezing period.

[0110] Example 2

[0111] The reoxygenation, anti-blocking and / or anti-freezing applications of the water regulating pool system in Example 1.

[0112] In this embodiment, after the sewage is precipitated and filtered by the upstream pretreatment system, it enters the upper submerged flow wetland unit 1 in a bottom-in and top-out water distribution mode. The dissolved oxygen in the sewage is relatively low, and the anaerobic reaction process mainly occurs in the upper submerged flow wetland unit 1. When the sewage is collected by the upper water collecting pipe 6-1 in the downstream area of ​​the upper submerged flow wetland unit 1 and enters the water regulating tank 5 through the water inlet movable bend 8 of the water regulating tank inlet 7, at this time, the angle (0-90°) between the water inlet movable bend 8 and the horizontal plane can be adjusted according to the operation mode described above when aeration and reoxygenation are required, in combination with the dissolved oxygen concentration demand, so that the height of the outlet end of the water inlet movable bend 8 can be adjusted, so that a certain drop is formed between the outlet end of the water inlet movable bend 8 and the water surface of the water regulating tank 5, and at the same time, the water diversion cap 16 installed at the outlet end of the water inlet movable bend 8 is used to spray water for aeration to form a water fountain, and in this process, the water body inside the water tank is reoxygenated.

[0113] After running for a period of time (for example, 5-6 months), if the upper submerged flow wetland unit 1 may be partially blocked due to the accumulation of suspended particles or biofilm, it can be adjusted according to the operating mode described above when anti-blocking and dredging are required. Specifically, the water level in the upper submerged flow wetland unit 1 can be made to reach the highest water level by rotating the water inlet movable bend pipe 8 to a vertical position; then the water outlet movable bend pipe 11 is rotated to a horizontal position, and the valve of the second water regulating tank straight pipe 20 is fully opened to discharge the water in the water regulating tank 5 to the lowest water level; then the valve of the second water regulating tank straight pipe 20 is closed, the water inlet movable bend pipe 8 is rotated to a horizontal position, and the valve of the first water regulating tank straight pipe 19 is fully opened. Due to the pressure formed by the high water level in the upper submerged flow wetland unit 1, the water inside the upper submerged flow wetland unit 1 flows out in the shortest time. Due to the accelerated water flow, the metabolites or aged biofilms formed in the gaps and surface of the wetland matrix can be discharged from the upper submerged flow wetland unit 1 through the water flow to the greatest extent, thereby realizing the dredging of the upper submerged flow wetland unit 1 without digging the matrix. After that, it can be restored to the normal operation state, preferably by distributing water to the lower submerged wetland unit 2 according to the following method 1 or method 2 to reduce the suspended particles entering the lower submerged wetland unit 2: Method 1, the outlet movable bend pipe 11 is rotated to a vertical position, and the valve of the second water regulating tank straight pipe 20 is opened, so that the water flowing from the water regulating tank 5 to the lower submerged wetland unit 2 is the water from the upper layer of the water regulating tank 5; at the same time, the filter cap 17 on the water inlet end of the outlet movable bend pipe 11 can also play the role of intercepting suspended matter. Method 2, the water in the water regulating tank 5 flows to the lower submerged wetland unit 2 through the upper water regulating tank outlet 10. During the retention of water in the water regulating tank 5, some suspended particles in the water will precipitate. At this time, the angle of the upper water regulating tank outlet 10 or the outlet movable bend 11 is adjusted to the upper water outlet, so that the lower submerged flow wetland unit 2 is distributed with water, which can reduce the entry of suspended particles into the lower wetland unit to a certain extent, and reduce the risk of blockage of the lower wetland unit. The silt deposited at the bottom of the water regulating tank 5 can be discharged by connecting the connecting pipe 13 at the bottom of the water regulating tank to the backwashing system to regularly flush the water regulating tank 5. When operating in the freezing period in the north, it is necessary to regulate the operation mode of the wetland through the water regulating tank system to ensure that the wetland can operate normally during the freezing period. The operation mode when antifreeze is required can be regulated as described above. In this embodiment, before the freezing period begins, the water level of the upper submerged flow wetland unit 1 is adjusted to the highest water level by rotating the water inlet movable elbow 8 to a vertical position or closing the valve of the first water regulating tank straight pipe 19, and natural freezing is used to form an ice cover on the upper part of the wetland. During the formation of the ice cover, the wetland can be suspended until the ideal frozen layer thickness is reached (specifically depending on the thickness of the ice layer of the local still water body), and the upper surface of the frozen layer is covered with thermal insulation material.Then, by adjusting the angle between the water inlet movable bend 8 and the horizontal plane, the water level in the upper submerged flow wetland unit 1 is appropriately lowered, so that a 10 cm air isolation layer is formed between the water level and the frozen layer, and the water below the isolation layer can flow normally; in this step, if the valve of the first water regulating tank straight pipe 19 is closed during the operation of forming the frozen cover, the valve of the first water regulating tank straight pipe 19 needs to be opened in the step of forming the air isolation layer. At this time, according to the dissolved oxygen situation, if aeration and reoxygenation are required, the operation mode of aeration and reoxygenation described above can be referred to, such as adjusting the angle of the water outlet movable bend to ensure that the water level in the water regulating tank 5 is lower than the height of the outlet end of the water inlet movable bend 8, so that there is a 20 cm drop between the two to achieve reoxygenation; at the same time, the water inflow of the lower submerged flow wetland unit 2 can be reduced by reducing the valve of the second water regulating tank straight pipe 20. Since the low temperature in winter affects the treatment effect of the wetland system, it is recommended to maintain low water level and low water volume. At the same time, the cover plate on the top of the water regulating tank 5 is covered with an insulation layer to prevent the water in the water regulating tank 5 from freezing.

[0114] In this embodiment, once it is found that the purification effect of the water discharged from the upper submerged flow wetland unit 1 is not ideal (for example, it cannot meet the expected water quality index requirements), the connecting pipe 13 at the bottom of the water regulating tank 5 can be connected to the reflux system, and the water body can be returned to the pretreatment system for repeated purification.

[0115] Application Example 1

[0116] The water regulating pool system of the present invention is applied to a domestic sewage artificial wetland treatment project of a school in rural Beijing. The artificial wetland area is 500m 2 , daily treatment of domestic sewage 120m 3 The artificial wetland system consists of vertical subsurface flow and horizontal subsurface flow wetland units connected in series in multiple stages + biological ponds (i.e., biological ponds are set downstream of the multi-stage series of subsurface flow wetland units). The subsurface flow wetland units at each level are layered with fillers of different particle sizes and planted with wetland plants such as reeds, cattails, and calamus; the water regulating pool system described above is set between the upper subsurface flow wetland unit 1 and the lower subsurface flow wetland unit 2 (the structure can be seen in Figure 1-6 ). The main pipeline of the system adopts UPVC pipe with a diameter of 12 cm. Using the water regulating pool system of the present invention, the effluent of the artificial wetland system is required to meet the Class B standard in the Beijing local standard "Water Pollutant Discharge Standard for Rural Domestic Sewage Treatment Facilities" (DB11 / 1612-2019) (Table 1).

[0117] Domestic sewage enters the artificial wetland after sedimentation and pretreatment in the septic tank. The water distribution mode of the upper artificial wetland unit is bottom-in and top-out. It flows upward to the top of the upper submerged flow wetland unit 1, is collected by the water collecting pipe, and enters the water inlet movable elbow 8 through the water inlet of the water regulating tank, and then flows to the water regulating tank 5; according to the dissolved oxygen demand of the water body, by adjusting the angle (0-90°) between the water inlet movable elbow 8 and the horizontal plane, and at the same time, it can also cooperate with the valve opening of the first water regulating tank straight pipe 19, so as to synchronously realize the water inflow and aeration effect control of the water regulating tank 5; at the same time, by adjusting the angle (0-90°) between the outlet movable elbow and the horizontal plane, and coordinating with the opening of the second water regulating tank straight pipe 20 (if necessary, the opening of the third water regulating tank straight pipe 21 can also be adjusted), the water inflow control of the lower wetland unit is realized. The water inlet movable bend pipe 8 of the water regulating pool adopts a UPVC pipe with a diameter of 12 cm. When the water outlet end of the water inlet movable bend pipe 8 is in a vertical position, the height difference between the outlet water and the highest water surface of the water regulating pool 5 is 30 cm, and the aeration effect is obvious (Table 1).

[0118] Domestic sewage raw water COD, TN, TP and NH4 + -N were 300-400mg / L, 80-90mg / L, 4-5mg / L and 20-30mg / L respectively. After sedimentation and pretreatment in the septic tank, they entered the artificial wetland system for treatment. The inlet and outlet water quality of the artificial wetland system are shown in Table 1.

[0119] Table 1 Water quality and relevant standards of inlet and outlet water of artificial wetlands

[0120]

[0121]

[0122] Due to the effect of the water regulating pool system, the DO of the water body is significantly improved, and the removal effect of the subsurface flow wetland on ammonia nitrogen is enhanced. At the same time, various effluent indicators can reach and exceed the Class B standard for rural domestic sewage discharge in Beijing, verifying the effectiveness of the artificial wetland water regulating pool system in the present invention.

[0123] Those skilled in the art will appreciate that, based on the teachings of this specification, some modifications or adjustments may be made to the present invention, and these modifications or adjustments should also be within the scope defined by the claims of the present invention.

Claims

1. An operating method for a water regulating pool system for reoxygenation, anti-blocking and / or anti-freezing of a subsurface artificial wetland, characterized in that: The water regulating pool system is arranged between the upper submerged flow wetland unit and the lower submerged flow wetland unit of the submerged flow artificial wetland system; The water regulating tank system includes a water regulating tank, a water regulating tank straight pipe with a valve, a connecting pipe with a valve, and an inlet movable elbow pipe and an outlet movable elbow pipe arranged in the water regulating tank; the water regulating tank straight pipe includes a first water regulating tank straight pipe and a second water regulating tank straight pipe; a water regulating tank water inlet is provided at the lower part of the upstream wall of the water regulating tank, and the first water regulating tank straight pipe is installed on the water regulating tank water inlet; a lower water regulating tank water outlet is provided at the lower part of the downstream wall of the water regulating tank, and the second water regulating tank straight pipe is installed on the lower water regulating tank water outlet; A water distribution pipe is provided in the upstream area of ​​the upper submerged flow wetland unit, and a water collecting pipe is installed in the downstream area of ​​the upper submerged flow wetland unit; the water regulating tank is connected to the upper submerged flow wetland unit through the first water regulating tank straight pipe; the water inlet end of the first water regulating tank straight pipe is connected to the water collecting pipe of the upper submerged flow wetland unit, the water outlet end of the first water regulating tank straight pipe is movably connected to the water inlet movable bend pipe, and the water inlet movable bend pipe can rotate between a horizontal position and a vertical position relative to the first water regulating tank straight pipe; A water distribution pipe is installed in the upstream area of ​​the lower submerged flow wetland unit, and the water regulating tank is connected to the lower submerged flow wetland unit through the second water regulating tank straight pipe; the water inlet end of the second water regulating tank straight pipe is movably connected to the water outlet movable elbow pipe, and the water outlet movable elbow pipe can rotate between a horizontal position and a vertical position relative to the second water regulating tank straight pipe; the water outlet end of the second water regulating tank straight pipe is connected to the water distribution pipe in the lower submerged flow wetland unit; a water collecting pipe is provided in the downstream area of ​​the lower submerged flow wetland unit; (A) When aeration and reoxygenation are required, the operation method comprises the following steps: By rotating the water inlet movable bend pipe and / or rotating the water outlet movable bend pipe so that the height of the water outlet end of the water inlet movable bend pipe is higher than the water level of the water regulating pool to form a waterfall, so that water from the upper submerged flow wetland unit flows out through the water outlet end of the water inlet movable bend pipe to form a fountain for aeration and reoxygenation; (B) When anti-blocking and dredging is required, the operation method includes the following steps: B1) rotating the water inlet movable elbow to a vertical position and / or closing the valve of the first water regulating tank straight pipe, so that the upper submerged flow wetland unit reaches its highest water level; at the same time, rotating the water outlet movable elbow to a horizontal position, and fully opening the valve of the second water regulating tank straight pipe, so that the water in the water regulating tank is discharged to the lowest water level; B2) Then close the valve of the second water regulating tank straight pipe, rotate the water inlet movable elbow to a horizontal position, and fully open the valve of the first water regulating tank straight pipe, so that the water in the upper submerged flow wetland unit is accelerated to flow to the water regulating tank under high water pressure, thereby flushing and desilting the upper submerged flow wetland unit; B3) rotating the outlet movable elbow and opening the valve of the second water regulating tank straight pipe, so that the water flowing from the water regulating tank to the lower submerged flow wetland unit is water from the upper layer of the water regulating tank; or, an upper water regulating tank outlet connected to the lower submerged flow wetland unit is opened on the upper part of the downstream wall of the water regulating tank, and the water in the water regulating tank flows to the lower submerged flow wetland unit through the upper water regulating tank outlet; (C) When antifreeze is required, the operation method includes the following steps: Before entering the freezing period, the upper submerged flow wetland unit reaches its highest water level by rotating the water inlet movable elbow to a vertical position and / or closing the valve of the first water regulating tank straight pipe, and after entering the freezing period, a frozen layer is formed on the upper part of the upper submerged flow wetland unit; Then, the water inlet movable elbow is rotated to form an air isolation layer of 0.5-15 cm between the water level in the upper submerged flow wetland unit and the frozen layer. If the valve of the first water regulating tank straight pipe is closed during the process of forming the frozen layer, the valve of the first water regulating tank straight pipe is opened at the same time during the step of forming the air isolation layer. A cover plate is provided on the top of the water regulating tank, and a thermal insulation layer is covered on the top of the cover plate to prevent the water in the water regulating tank from freezing; (D) When it is necessary to drain the water in the subsurface wetland unit, the operation method comprises the following steps: When the water collecting pipe of the upper submerged flow wetland unit is installed at the lower part of the downstream area, the water in the upper submerged flow wetland unit is discharged into the water regulating pool through the water inlet of the water regulating pool, and then discharged into the lower submerged flow wetland unit from the water regulating pool, or the water discharged into the water regulating pool is discharged outward through the connecting pipe installed at the lower part of the water regulating pool, thereby emptying the water in the upper submerged flow wetland unit; When the water collecting pipes of the upper submerged flow wetland unit or the lower submerged flow wetland unit are installed at the upper part of the respective downstream areas, the respective water bodies are emptied by installing drain pipes in the upper submerged flow wetland unit or the lower submerged flow wetland unit, respectively.

2. The operating method according to claim 1, characterized in that: When the water inlet movable bend pipe is rotated to a vertical position, the height of the water inlet movable bend pipe does not exceed the highest water level of the upper submerged flow wetland unit; When the water inlet movable bend pipe is rotated to a vertical position, the height of the water outlet end is 10-30 cm higher than the height of the water inlet end when the water outlet movable bend pipe is rotated to a vertical position.

3. The operating method according to claim 2, characterized in that: The water outlet end of the water inlet movable elbow is installed with a water dividing cap; the water inlet end of the water outlet movable elbow is installed with a filter cap; And / or, a cover plate is provided on the top of the water regulating tank.

4. The operating method according to claim 2, characterized in that: The distance between the water inlet of the water regulating pool and the bottom of the downstream area of ​​the upper submerged flow wetland unit is 10-30 cm; The distance between the water outlet of the lower water regulating pool and the bottom of the lower submerged flow wetland unit is 10-50 cm.

5. The operating method according to claim 2, characterized in that: The water regulating tank straight pipe also includes a third water regulating tank straight pipe; An upper water regulating pool outlet connected to the lower submerged flow wetland unit is provided on the upper part of the downstream wall of the water regulating pool, the third water regulating pool straight pipe is installed on the upper water regulating pool outlet, and the third water regulating pool straight pipe is connected to the water distribution pipe in the lower submerged flow wetland unit; The outlet of the upper water regulating tank is flush with the upper surface of the substrate of the lower submerged flow wetland unit, and when the water inlet movable bend pipe is rotated to a vertical position, the position of the outlet of the upper water regulating tank is 10-20 cm lower than the outlet end of the water inlet movable bend pipe.

6. The operating method according to claim 5, characterized in that: The water distribution pipe of the upper submerged flow wetland unit is installed at the upper part or lower part of the upstream area of ​​the upper submerged flow wetland unit, and the water collection pipe of the upper submerged flow wetland unit is installed at the lower part or upper part of the downstream area in the upper submerged flow wetland unit accordingly; The water distribution pipe of the lower submerged flow wetland unit is installed at the upper or lower part of the upstream area of ​​the lower submerged flow wetland unit, and the water collection pipe of the lower submerged flow wetland unit is correspondingly installed at the lower or upper part of the downstream area in the lower submerged flow wetland unit.

7. The operating method according to any one of claims 1 to 6, characterized in that: The water regulating pool system is connected to the reflux system through the connecting pipe, and / or the water regulating pool system is connected to the external discharge system through the connecting pipe, and / or the water regulating pool system is connected to the backwashing system through the connecting pipe; The connecting pipe is located at the lower part of the water regulating tank, and a plurality of water inlet holes are opened on the connecting pipe.

8. The operating method according to claim 7, characterized in that: The connecting pipe is 5-10 cm away from the bottom of the water regulating tank.

9. The operating method according to any one of claims 1 to 6, characterized in that: The above (C) further includes the following steps: Before the frozen layer is formed, a support structure is provided on the substrate surface of the upper subsurface flow wetland unit to support the frozen layer; And / or, covering the surface of the frozen layer with a thermal insulation material.

10. The operating method according to claim 1, characterized in that: In step B3), the rotating the movable water outlet elbow is to rotate the movable water outlet elbow to a vertical position.

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