Modularized in-situ ecological water purification dam

Abstract

The utility model belongs to the field of water ecological restoration engineering, and relates to a modularized in-situ ecological water purification dam. The in-situ ecological water purification dam comprises a left vertical flow constructed wetland, a middle grouted stone dam body and a right vertical flow constructed wetland, a filter dam is combined with the constructed wetlands, in-situ remediation is performed on a river, and the water quality of a water body is effectively improved; by using the flow-separation ball filler, functional microorganisms are rapidly enriched, and the water permeability is good; in addition, blockage can be effectively prevented by adjusting the water inlet mode without providing backwashing power. The modularized in-situ ecological water purification dam is stable in permeability coefficient, not prone to blockage, good in water purification effect, high in ecologicalization and landscape performance, low in cost and maintenance cost, easy to manage and high in application and popularization value.

Description

Technical Field

[0001] The utility model belongs to the field of water ecological restoration engineering and relates to a modular in-situ ecological water purification dam. Background Art

[0002] In the 20th century, people began to use constructed wetlands to repair water bodies such as rivers. The main types of wetlands used were surface flow constructed wetlands, subsurface flow constructed wetlands, and vertical flow constructed wetlands, which had the characteristics of large buffer capacity, good treatment effect, simple process, and low operation cost. However, they were often set up in bypasses, with disadvantages such as large land occupation area, obvious seasonality, poor pollutant treatment effect, easy blockage, and after running for a certain period of time, they completely lost the purification function, and even hindered the water circulation, which was not conducive to water conservancy safety.

[0003] In addition, most of the current dams for rivers are masonry dams, and the filtration technology mainly focuses on physical filtration, without biological purification function, with single function, unable to effectively remove suspended solids SS, nitrogen, phosphorus, and organic matter in river sewage. Additionally, it may also lead to poor overall water body fluidity, further deterioration of the water body, and no vegetation coverage, with poor landscape, and is not suitable for application in urban rivers.

[0004] To solve these problems, ecological water purification dams have begun to be applied in the in-situ ecological restoration of rivers. Although some can improve water quality to a certain extent, there are still problems such as poor water quality improvement effect, unfixed permeability coefficient, and easy blockage. Utility model patent 202223075052.4 discloses an ecological water purification dam, which uses Myriophyllum aquaticum as the main body of plant restoration, and combines biological fillers to effectively improve the degradation rate of water body pollutants and the filtration of two dams. However, it is set up in bypass and cannot treat the water body inside the river, requires additional land resources, and with the operation, the blockage problem becomes more and more obvious, and it will lose the purification function subsequently.

[0005] In view of the above situation, the utility model provides a modular in-situ ecological water purification dam, which combines a filtration dam with a constructed wetland to conduct in-situ restoration of river water bodies, does not require additional land resources, has an obvious effect on improving water quality, can solve the blockage problem without power, is maintenance-free, and has strong ecological and landscape features. Summary of the Utility Model

[0006] The utility model provides a modular in-situ ecological water purification dam, which combines a filtration dam with a constructed wetland, has the advantages of being able to in-situ purify the water quality of river water bodies and solve the blockage problem of traditional wetlands without power, and can provide certain ideas and technical support for the ecological treatment and restoration of current water bodies such as rivers.

[0007] The technical problems to be solved by the utility model are realized through the following technical solutions:

[0008] A modular in-situ ecological water purification dam, characterized in that the in-situ ecological water purification dam sequentially includes, from left to right: a left vertical-flow constructed wetland, a middle masonry dam body, and a right vertical-flow constructed wetland.

[0009] The water inlet mode of the in-situ ecological water purification dam is as follows: water enters the left vertical-flow constructed wetland through the upper left water inlet gate or the lower left water distribution pipe and valve of the left vertical-flow constructed wetland. After treatment, it enters the right vertical-flow constructed wetland through the water distribution pipe on the middle masonry dam body. The water body treated by the ecological water purification dam flows to the water body through the water distribution pipe. At the same time, in order to prevent wetland blockage and save external power, when the water level of the left vertical-flow constructed wetland of the in-situ ecological water purification dam is 20 cm or more higher than the normal water level, the water inlet direction of the left vertical-flow constructed wetland is changed. When the water level returns and then is 20 cm or more higher than the normal water level again, the water inlet direction of the left vertical-flow constructed wetland is changed back, and the water inlet mode is adjusted accordingly.

[0010] Among them, a water inlet gate is arranged at the upper left position of the left vertical-flow constructed wetland, and a water distribution pipe and valve are arranged at the bottom left position; two groups of upper and lower water distribution pipes are arranged in the right vertical-flow constructed wetland, and the water flow direction is opposite to that of the left vertical-flow constructed wetland. The water distribution pipes in the two vertical-flow constructed wetlands on both sides can be used as water distribution pipes or as water collection pipes, which is specifically determined according to the water flow direction.

[0011] The structures of the vertical-flow constructed wetlands on both sides of the middle masonry dam body are, from top to bottom in sequence: aquatic plants, planting substrate, geotextile, and filler area.

[0012] The filler area of the two vertical-flow constructed wetlands on both sides is filled with floating balls, and the diameter of the floating balls is 6 - 20 cm. The filler filled in the floating balls includes one or several of waste biomass, minerals, and polymer materials. The particle size of the filler is 0.5 - 4 cm, and the filling ratio of the filler is 70 - 90%. Among them, the waste biomass is an attachment carrier for denitrification and other functional bacteria and a source of natural carbon, and is selected from one or several of walnut shells, bone grains, corn cobs, and coconut shells; the minerals can physically adsorb pollutants in the water body, provide space for microorganisms to attach and grow, available inorganic nutrients, and provide iron, sulfur, etc. as electron donors for autotrophic denitrifying bacteria, and are selected from one or several of zeolites, volcanic rocks, activated carbon, pyrite, slag, and lightweight glass stones; the polymer materials can also be used as carriers for microbial growth and enrichment, and are selected from one or several of high-density polyethylene, high-density polypropylene, polystyrene, and polyvinyl chloride. The ratio of the waste biomass, minerals, and polymer materials is 5 - 10:5 - 10:0.5 - 3.

[0013] The planting substrate described above is a granular substrate or a planting blanket, which serves to facilitate the planting of aquatic plants and filter the suspended solids in the water body. When the planting substrate is a granular substrate, its particle size is 0.5 - 2 cm, and the laying thickness is 20 - 40 cm, and it is selected from one or two of volcanic rock, gravel, and zeolite. When the planting substrate is a planting blanket, through holes with a diameter of 20 - 50 mm are provided on the planting blanket, and the through holes are used to fix the roots of submerged plants and emergent plants.

[0014] The aquatic plants described above include submerged plants and emergent plants, which can play the roles of purifying water quality, continuously supplying oxygen to the water body, and increasing the diversity of the water body ecosystem. The aquatic plants planted in the left vertical-flow constructed wetland are submerged plants, and all the existing submerged plants used for water body restoration are applicable to the present utility model. In order to reduce costs and improve the restoration effect at the same time, the submerged plants are selected from one or several of Vallisneria natans, Hydrilla verticillata, Myriophyllum spicatum, Potamogeton crispus, Potamogeton distinctus, and Elodea nuttallii. The aquatic plants planted in the right vertical-flow constructed wetland are emergent plants. In order to increase the water purification effect and economic benefits, the emergent plants are selected from one or several of Iris pseudacorus, Oenanthe javanica, Zizania latifolia, Sagittaria trifolia, Eleocharis dulcis, Myriophyllum aquaticum, Phragmites australis, and Juncus effusus.

[0015] Crayfish and loach are cultured in the two-sided vertical-flow constructed wetlands on both sides to further dredge the voids in the filler area and the planting substrate, prevent the wetland from being blocked, and increase economic benefits for river restoration.

[0016] The width of the in-situ ecological water purification dam is the same as the width of the river, and the length is 1 / 40 - 1 / 20 of the total length of the river to be treated. The distance between the ecological water purification dams is determined according to the actual situation of the river.

[0017] The width of the two-sided vertical-flow constructed wetlands on both sides is the same as the width of the river, and the length ratio of the left vertical-flow constructed wetland to the right vertical-flow constructed wetland is 1:1.5 - 3.0. The width of the middle masonry dam body is the same as the width of the river, the thickness is 50 - 80 cm, and the height is determined according to the actual situation of the river.

[0018] The emergent plants can be harvested regularly, the economic aquatic plants can be directly picked and sold, and other plants can be processed as feed to obtain certain economic benefits. In addition, the crayfish and loach in the wetland can be salvaged regularly to realize economic value.

[0019] The characteristics of the present utility model are as follows: The modular in-situ ecological water purification dam combines a filtering dam with an artificial wetland, enabling in-situ restoration of rivers. It effectively addresses the difficulties and pain points of the grouted stone intercepting dam and traditional artificial wetlands. Through the synergistic method of physical, microbial reaction, and ecological treatment, it can effectively improve the water quality of river water, reduce indicators such as COD, nitrogen, and phosphorus, and raise the water quality standard level to Class IV surface water standard or above. The filler area of the modular in-situ ecological water purification dam uses floating balls with a large specific surface area, which enables the rapid growth and enrichment of functional microorganisms, maintains a high biomass, and can also achieve aerobic, anoxic, and anaerobic regional environments, effectively removing pollutants. Moreover, it has good water permeability and is not easily blocked. The water inlet mode of the modular in-situ ecological water purification dam can be adjusted, effectively preventing blockage, without the need to provide the power for backwashing, saving operation and maintenance costs. The configuration of aquatic plants in the modular in-situ ecological water purification dam can transport oxygen to the water body, increase the dissolved oxygen in the water body, improve the interaction between plants and microorganisms, enhance the pollutant removal effect, and at the same time, while achieving a certain degree of landscape, certain economic benefits can be obtained through harvesting and processing. The modular in-situ ecological water purification dam has a stable permeability coefficient, is not easily blocked, has good water purification quality effect, strong ecological and landscape properties, low cost and maintenance expenses, and simple management, and has high popularization and application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic cross-sectional view of a modular in-situ ecological water purification dam

[0021] REFERENCE NUMERALS

[0022] 1 - Left vertical-flow artificial wetland; 2 - Right vertical-flow artificial wetland; 3 - Water inlet gate; 4 - Submerged plants; 5 - Filler area; 6 - Floating balls; 7 - Distribution pipe; 8 - Middle grouted stone dam body; 9 - Emergent plants; 10 - Valve; 11 - Geotextile; 12 - Planting substrate. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The present utility model will be further described in detail below with reference to the drawings and through examples.

[0024] As Figure 1 shown, a modular in-situ ecological water purification dam is as follows:

[0025] The modular in-situ ecological water purification dam sequentially includes from left to right: a left vertical-flow artificial wetland 1, a middle grouted stone dam body 8, and a right vertical-flow artificial wetland 2.

[0026] Among them, an influent gate 3 is arranged at the upper left position of the left vertical-flow constructed wetland 1, and a water distribution pipe 7 and a valve 10 are arranged at the bottom left position; the right vertical-flow constructed wetland 2 is provided with two sets of upper and lower water distribution pipes 7, and the water flow direction is opposite to that of the left vertical-flow constructed wetland 1. The water distribution pipes 7 in the two vertical-flow constructed wetlands 1 and 2 on both sides can be used as water distribution pipes or as water collection pipes, specifically determined according to the water flow direction.

[0027] The influent mode of the in-situ ecological water purification dam is as follows: water enters the left vertical-flow constructed wetland 1 through the influent gate 3 at the upper left of the left vertical-flow constructed wetland 1, or through the water distribution pipe 7 and the valve 10 at the lower left. After preliminary treatment, it enters the right vertical-flow constructed wetland 2 through the water distribution pipe 7 on the middle masonry dam body 8, and the water body after further treatment flows to the water body through the water distribution pipe 7. In order to prevent wetland blockage and save external power, when the water level of the left vertical-flow constructed wetland 1 of the in-situ ecological water purification dam is 20 cm or more higher than the normal water level, the influent direction of the left vertical-flow constructed wetland 1 is changed. When the water level returns and then is 20 cm or more higher than the normal water level again, the influent direction of the left vertical-flow constructed wetland 1 is changed back, and the influent mode is adjusted accordingly.

[0028] The right vertical-flow constructed wetland 2 is provided with two sets of upper and lower water distribution pipes 7, and the water flow direction is opposite to that of the left vertical-flow constructed wetland 1.

[0029] The structures of the two vertical-flow constructed wetlands 1 and 2 on both sides are, from top to bottom in sequence, aquatic plants, planting substrate 12, geotextile 11, and packing area 5.

[0030] The packing area 5 of the two vertical-flow constructed wetlands 1 and 2 on both sides is filled with floating balls 6, and the diameter of the floating balls 6 is 6 - 20 cm. The packing filled in the floating balls 6 includes one or several of waste biomass, minerals, and polymer materials. The particle size of the packing is 0.5 - 4 cm, and the filling ratio of the packing is 70 - 90%. Among them, the waste biomass is an attachment carrier for denitrification and other functional bacteria and a source of natural carbon, selected from one or several of walnut shells, bone grains, corn cobs, and coconut shells; the minerals can physically adsorb pollutants in the water body, provide space for microorganisms to attach and grow, available inorganic nutrients, and provide iron, sulfur, and other electron donors for autotrophic denitrifying bacteria, selected from one or several of zeolites, volcanic rocks, activated carbon, pyrite, slag, and light expanded clay aggregate; the polymer materials can also be used as carriers for microorganism growth and enrichment, selected from one or several of high-density polyethylene, high-density polypropylene, polystyrene, and polyvinyl chloride. The ratio of the biomass, minerals, and polymer materials is 5 - 10:5 - 10:0.5 - 3.

[0031] The planting substrate 12 described above is a granular substrate or a planting blanket, which is used to facilitate the planting of aquatic plants and filter the suspended substances in the water body. When the planting substrate 12 is a granular substrate, its particle size is 0.5 - 2 cm, and the laying thickness is 20 - 40 cm, and it is selected from one or two of volcanic rock, gravel, and zeolite. When the planting substrate 12 is a planting blanket, through holes with a diameter of 20 - 50 mm are opened on the planting blanket, and the through holes are used to fix the roots of the submerged plants 4 and the emergent plants 9.

[0032] The aquatic plants described above include submerged plants 4 and emergent plants 9, which can play the roles of purifying water quality, continuously supplying oxygen to the water body, and increasing the diversity of the water body ecosystem. The aquatic plants planted in the left vertical - flow constructed wetland 1 are submerged plants 4. All existing submerged plants used for water body restoration are applicable to the present utility model. In order to reduce costs and improve the restoration effect at the same time, the submerged plants 4 are selected from one or several of Vallisneria natans, Hydrilla verticillata, Myriophyllum spicatum, Potamogeton crispus, Potamogeton distinctus, Elodea canadensis. The aquatic plants planted in the right vertical - flow constructed wetland 2 are emergent plants 9. In order to increase the water purification effect and economic benefits, the emergent plants 9 are selected from one or several of Iris pseudacorus, Oenanthe javanica, Zizania latifolia, Sagittaria trifolia, Eleocharis dulcis, Myriophyllum aquaticum, Phragmites australis, Juncus effusus.

[0033] Crayfish and loach are cultured in the two - side vertical - flow constructed wetlands 1 and 2 to further dredge the voids in the filler area and the planting substrate 12, prevent the wetland from being blocked, and increase economic benefits for river restoration.

[0034] The width of the in - situ ecological water purification dam is the same as the width of the river, and the length is 1 / 40 - 1 / 20 of the total length of the river to be treated. The distance between the in - situ ecological water purification dams is determined according to the actual situation of the river.

[0035] The widths of the two - side vertical - flow constructed wetlands 1 and 2 are the same as the width of the river, and the length ratio of the left vertical - flow constructed wetland 1 to the right vertical - flow constructed wetland 2 is 1:1.5 - 3. The width of the middle masonry dam body 8 is the same as the width of the river, the thickness is 50 - 80 cm, and the height is determined according to the actual situation of the river.

[0036] The emergent plants 9 can be harvested regularly. Economically valuable aquatic plants can be directly picked and sold, and other plants can be processed as feed to obtain certain economic benefits. In addition, the crayfish and loach in the two - side vertical - flow constructed wetlands 1 and 2 can be salvaged regularly to realize economic value.

[0037] Embodiment

[0038] The modular in-situ ecological water purification dam of the present utility model is used to repair a certain river course. The length of the river course is about 10 km. Due to external pollution such as non-point source and point source pollution, the water quality is inferior to Class V, and the transparency is low. The water inlet mode of the in-situ ecological water purification dam is as follows: the river water body enters through the upper left water inlet gate of the left vertical-flow constructed wetland, and the water after preliminary treatment flows through the water distribution pipe of the middle masonry dam body into the right vertical-flow constructed wetland in the direction of flowing in from the bottom and flowing out from the top for further treatment. When observing the in-situ ecological water purification dam treating this river course for 8 months, the water level of the left vertical-flow constructed wetland is 22 cm higher than the normal water level. At this time, the upper water inlet gate is closed, and the water enters through the lower water distribution pipe of the left vertical-flow constructed wetland. After operating for about 10 days, the water level returns to normal. After operating for about 6.5 months, the water level of the left vertical-flow constructed wetland is about 20 cm higher than the normal water level. The left upper water inlet gate is reopened, and the lower water distribution pipe of the left vertical-flow constructed wetland is closed. After that, the water inlet mode is adjusted according to this. The planting substrates of the two vertical-flow constructed wetlands on both sides are volcanic rock and zeolite, with an average particle size of 1.0 cm and a laying thickness of 30 cm. The submerged plants in the left wetland are Vallisneria natans, Myriophyllum spicatum, and Elodea nuttallii. The emergent plants in the right wetland are Iris pseudacorus, Oenanthe javanica, Zizania latifolia, Sagittaria trifolia, and Myriophyllum aquaticum. The filling ratio of the floating balls in the filler area of the two vertical-flow constructed wetlands on both sides is 70%. The particle size of the fillers filled in the floating balls, which are waste biomass, minerals, and polymer materials, is 1.5 cm, and the ratio of the three materials is 5:5:1. The waste biomass is walnut shell, bone granule, and corn cob. The minerals are zeolite, pyrite, and glass light stone. The polymer materials are high-density polyethylene and high-density polypropylene. The lengths of the left vertical-flow constructed wetland and the right vertical-flow constructed wetland are 200 m and 300 m respectively, and the thickness of the middle masonry dam body is 60 cm. The distance between the two in-situ ecological water purification dams set in the river course is 600 m. During the operation process, plants are regularly harvested and animals are salvaged, and they are directly sold or processed. The water quality of the river course is monitored for a long time. After the river course is repaired by using the modular in-situ ecological water purification dam of the present utility model, the annual average water quality of the river course reaches the standard of Class III surface water, and the specific indicators are shown in Table 1.

[0039] Table 1 Water body indicators after repair

[0040] Table 2 Water body indicators after repair

[0041] Raw water After treatment COD (mg / L) 45.71 19.80 TN (mgN / L) 6.23 0.97 <![CDATA[NH4 + (mgN / L)]]> 1.14 0.44 <![CDATA[NO3 - (mgN / L)]]> 5.01 0.49 <![CDATA[PO4 3- (mgP / L)]]> 0.83 0.16 Turbidity (NTU) 40 15

[0042] Example

[0043] A 30-kilometer-long section of a river was polluted, and the water quality was inferior to Class V, with low transparency. The modular in-situ ecological water purification dam of the present utility model was used to repair this river section. The water inlet mode of this in-situ ecological water purification dam is as follows: The river water body enters through the lower distribution pipe of the left vertical-flow constructed wetland, and the water after preliminary treatment flows out from bottom to top and enters the right vertical-flow constructed wetland through the distribution pipe of the middle masonry dam body, and further treatment is carried out in the direction of flowing in from top to bottom and flowing out from bottom to top. When observing the treatment of this river section by this in-situ ecological water purification dam for 6 months, the water level of the left vertical-flow constructed wetland is 25 cm higher than the normal water level. At this time, the valve on the lower distribution pipe of the left vertical-flow constructed wetland is closed, and the upper water inlet gate on the left is opened. After operating for about 15 days, the water level returns to normal. After that, after operating for about 5 months, the water level of the left vertical-flow constructed wetland is 30 cm higher than the normal water level. The valve on the lower distribution pipe of the left vertical-flow constructed wetland is reopened, and the upper water inlet gate on the left is closed. After that, the water inlet mode is adjusted according to this. The planting substrates of the two vertical-flow constructed wetlands on both sides are planting blankets, with through holes having a diameter of 35 cm. The submerged plants planted in the left vertical-flow constructed wetland are Hydrilla verticillata, Myriophyllum spicatum, and Potamogeton distinctus. The emergent plants planted in the right vertical-flow constructed wetland are Oenanthe javanica, Sagittaria trifolia, Eleocharis dulcis, Myriophyllum aquaticum, and Juncus effusus. The filling ratio of the floating balls in the filler area of the two vertical-flow constructed wetlands on both sides is 90%. The particle size of the fillers filled in the floating balls, which are waste biomass, minerals, and polymer materials, is 3.6 cm, and the ratio of the three materials is 10:10:2.5. The waste biomass is bone particles and corncobs. The minerals are volcanic rock, pyrite, and light expanded clay aggregate. The polymer materials are polystyrene and polyvinyl chloride. The lengths of the left vertical-flow constructed wetland and the right vertical-flow constructed wetland are 200 m and 600 m respectively, and the thickness of the middle masonry dam body is 75 cm. The distance between the two in-situ ecological water purification dams set in this river section is 700 m. During the operation process, plants are regularly harvested and animals are salvaged, and they are directly sold or processed. After using the modular in-situ ecological water purification dam of the present utility model to repair this river section, the water quality of the river is monitored in the long term, and the annual average water quality of this river reaches the standard of Class IV surface water, and the specific indicators are shown in Table 2.

[0044] Table 2 Water Body Indicators after Repair

[0045] Table 2 Water Body Indicators after Repair

[0046] Raw water After treatment COD (mg / L) 68.56 29.76 TN (mgN / L) 12.46 1.49 <![CDATA[NH4 + (mgN / L)]]> 9.23 0.56 <![CDATA[NO3 - (mgN / L)]]> 3.01 0.96 <![CDATA[PO4 3- (mgP / L)]]> 1.12 0.29 Turbidity (NTU) 70 20

[0047] In Example 1 and Example 2, the modular in-situ ecological water purification dam of the present utility model was used to repair different river water bodies, and the COD, TN, NH4 + , NO3 - , PO4 3-The concentrations can all meet the Class IV standard and above specified in the Standard for Surface Water Environment Quality (GB3838-2002). The water purification effect is good, it is not easy to be blocked, the permeability coefficient is stable, the cost and maintenance cost are low, and the management is simple, ensuring the long-term stability of the river ecological system and having high popularization and application value. The above description does not constitute a limitation on the protection scope of the present utility model. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of this patent shall be included within the protection scope of the claims of this patent.

Claims

1. A modular in-situ ecological water purification dam, characterized by: The in-situ ecological water purification dam comprises, from left to right, a left vertical flow artificial wetland (1), a middle mortar masonry dam body (8), and a right vertical flow artificial wetland (2); the water intake of the in-situ ecological water purification dam is as follows: water enters the left vertical flow artificial wetland (1) through the left upper water intake gate (3) of the left vertical flow artificial wetland (1), or the left lower water distribution pipe (7) and valve (10), and the effluent after preliminary treatment passes through the water distribution pipe on the middle mortar masonry dam body (8) (7) Enter the right vertical flow artificial wetland (2), and the water body after further treatment flows to the water body through the distribution pipe (7); when the water level of the left vertical flow artificial wetland (1) of the in-situ ecological water purification dam is higher than the normal water level by 20 cm or more, the water inlet direction of the left vertical flow artificial wetland (1) is changed, and when the water level is higher than the normal water level by 20 cm or more after recovery, the water inlet direction of the left vertical flow artificial wetland (1) is changed back, and the water inlet method is adjusted accordingly thereafter.

2. A modular in-situ ecological water purification dam as claimed in claim 1, characterized in that: The structures of the vertical flow artificial wetland (1) on the left and the vertical flow artificial wetland (2) on the right are, from top to bottom, aquatic plants, planting matrix (12), geotextile (11), and filler area (5).

3. A modular in-situ ecological water purification dam as claimed in claim 2, characterized in that: The filler areas (5) of the left vertical flow artificial wetland (1) and the right vertical flow artificial wetland (2) are filled with flow balls (6), and the diameter of the flow balls (6) is 6-20 cm; the filler filled in the flow balls (6) includes one of waste biomass, minerals, and high molecular polymer materials, the particle size of the filler is 0.5-4 cm, and the filling ratio of the filler is 70-90%.

4. A modular in-situ ecological water purification dam as claimed in claim 2, characterized in that: The planting matrix (12) is a granular matrix or a planting blanket. When it is a granular matrix, its particle size is 0.5-2 cm, the laying thickness is 20-40 cm, and it is selected from volcanic rock, gravel, and zeolite; when it is a planting blanket, the planting blanket is provided with through holes with a diameter of 20-50 mm.

5. A modular in-situ ecological water purification dam as claimed in claim 2, characterized in that: The aquatic plants include submerged plants (4) and emergent plants (9). The aquatic plants planted in the left vertical flow artificial wetland (1) are submerged plants (4), which are selected from one or more of Vallisneria, Hydrilla, Myriophyllum spicate, Water Chestnut, Potamogeton, and Elodea; the aquatic plants planted in the right vertical flow artificial wetland (2) are emergent plants (9), which are selected from one or more of Evergreen Iris, Water Celery, Zizania latifolia, Sagittaria, Water Chestnut, Myriophyllum spicate, Phragmites australis, and Juncus wickii.

6. A modular in-situ ecological water purification dam as claimed in claim 1, characterized in that: The width of the in-situ ecological water purification dam is consistent with the width of the river channel, and the length is 1 / 40-1 / 20 of the total length of the river channel to be treated. The distance between the in-situ ecological water purification dams is determined according to the actual situation of the river channel.

7. A modular in-situ ecological water purification dam as claimed in claim 1, characterized in that: The width of the left vertical flow artificial wetland (1) and the right vertical flow artificial wetland (2) is consistent with the width of the river channel, and the length ratio of the left vertical flow artificial wetland (1) and the right vertical flow artificial wetland (2) is 1:1.5-1:3; the width of the middle mortar-laid stone dam body (8) is consistent with the width of the river channel, the thickness is 50-80cm, and the height is determined according to the actual situation of the river channel.

8. The modular in-situ ecological water purification dam according to claim 1, characterized in that: Crayfish and loaches are cultured in the vertical flow artificial wetland on the left (1) and the vertical flow artificial wetland on the right (2).

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