Aquaculture tail water treatment system and method for synchronously removing pollutants and antibiotics

Abstract

The invention discloses an aquaculture tail water treatment system and method for synchronously removing pollutants and antibiotics, the treatment system comprises an aquaculture pond, an ecological-physical coupling treatment system, an ecological treatment system and an ecological-chemical coupling treatment system, the interior of the ecological-physical coupling treatment system is divided into multiple stages of treatment areas connected in series, each stage of treatment area comprises a precipitation unit, an aeration unit and an ecological purification unit which are connected in series to form three-stage gradient ecological-physical coupling purification treatment; a floating wetland is constructed in the ecological treatment system, aquatic plants are planted, microorganisms are put in the ecological treatment system, the microorganisms and the aquatic plants synergistically metabolize and decompose antibiotic molecules and degrade pollutants, photocatalytic ecological materials are arranged in the ecological-chemical coupling treatment system, and the aquatic plants are planted in the ecological-chemical coupling treatment system. The method solves the problems that the salinity and total nitrogen treatment efficiency of traditional aquaculture tail water treatment are poor and antibiotics cannot be removed, has the advantages of being easy to operate and maintain, is wide in applicability and is suitable for aquaculture tail water purification treatment.

Description

Technical Field

[0001] The present invention belongs to the technical field of water environmental protection engineering, and particularly relates to an aquaculture tail water treatment system and method for synchronously removing pollutants and antibiotics. Background Art

[0002] China's aquaculture industry is currently in a stage of rapid development. With the popularization of intensive aquaculture models, a large amount of aquaculture tail water is generated during the aquaculture process. The salinity of aquaculture tail water is relatively high, and due to the input of aquaculture feed and anti-disease drugs, the tail water contains high concentrations of pollutants and antibiotic residues. The pollutants are mainly permanganate index, total nitrogen, total phosphorus, and suspended solids, and the antibiotics are mainly florfenicol and sulfamethoxazole. Florfenicol and sulfamethoxazole are widely used in aquaculture due to their high bactericidal ability.

[0003] If aquaculture tail water is directly discharged without treatment, it will cause environmental problems such as water eutrophication and ecological system imbalance, pose a huge pressure on the water environment, and cause potential harm to human health. In recent years, by vigorously adjusting the aquaculture industry structure, implementing pond standardization transformation, developing recirculating aquaculture, and promoting integrated rice-fish farming and other measures, the green and ecological transformation of the aquaculture industry has been promoted. However, the phenomenon of direct discharge of aquaculture tail water is still relatively common, and the technical demand for an efficient, economical, and ecological aquaculture tail water treatment mode is extremely urgent.

[0004] The traditional aquaculture tail water treatment system consists of 1 sedimentation tank, 1 aeration tank, 1 ecological purification tank, and 2 filter dams. The treatment process is as follows: Aquaculture tail water is collected and enters the sedimentation tank. After sedimentation, it is filtered through the filter dam, then enters the aeration tank for aeration, and then enters the filter dam for secondary filtration, and then enters the ecological purification tank, and finally is discharged into the receiving water body.

[0005] The traditional aquaculture tail water treatment technology has the following disadvantages: (1) The salinity of aquaculture tail water is relatively high, and a single ecological purification tank has a poor effect on salinity removal and cannot meet the requirements of up-to-standard discharge; (2) For aquaculture tail water with high total nitrogen, it may be necessary to add certain auxiliary agents, which increases the operating cost and restricts the recycling of the treated tail water; (3) It cannot achieve a good removal effect on antibiotics, and the antibiotic residue in the treated tail water is relatively large. Therefore, there is an urgent need for an ecological treatment optimization process for aquaculture tail water to replace the traditional aquaculture treatment technology.

[0006] After retrieval, the current research on optimizing and improving aquaculture tail water treatment systems has been made public. For example, a Chinese invention patent with the publication number: CN116813074A and the publication date: September 29, 2023, discloses an aquaculture tail water treatment process based on an enhanced three-pond two-dam MABR. It is characterized by a sedimentation unit, a first filtration area, an MABR biofilm purification area, a second filtration area, and an ecological purification area connected in sequence from front to back. Aquaculture tail water is discharged into the sedimentation unit, the first filtration area, the MABR biofilm purification area, the second filtration area, and the ecological purification area for treatment in sequence. Finally, after ensuring that the tail water meets the discharge limit values, it is discharged up to standard through the drain outlet. Its deficiency lies in that the problems of relatively high salinity and antibiotics in aquaculture tail water are not considered, and the tail water discharged after treatment still has problems of exceeding the salinity standard and antibiotic residues. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide an aquaculture tail water treatment system and method for synchronously removing pollutants and antibiotics in view of the above existing deficiencies.

[0008] To achieve the above technical objectives, the technical solutions adopted by the present invention are as follows:

[0009] An aquaculture tail water treatment system for synchronously removing pollutants and antibiotics includes an aquaculture pond, an ecological-physical coupling treatment system, an ecological treatment system, and an ecological-chemical coupling treatment system. The ecological-physical coupling treatment system is divided into multiple stages of serially connected treatment areas. Each stage of the treatment area includes a sedimentation unit, an aeration unit, and an ecological purification unit connected in series, constituting a three-stage gradient ecological-physical coupling purification treatment. The sedimentation unit is used to remove larger suspended particles in the water body. The aeration unit is used to aerate the water body, reduce the total phosphorus and permanganate index in the water body, and provide oxygen for aquatic animals. The ecological purification unit plants aquatic plants and releases aquatic animals. The aquatic plants and aquatic animals are used to convert nitrogen and phosphorus in the water body and reduce the water body salinity. A floating wetland is constructed in the ecological treatment system, planting aquatic plants and putting microorganisms. The microorganisms and aquatic plants synergistically metabolize and decompose antibiotic molecules and degrade pollutants. Photocatalytic ecological materials are arranged in the ecological-chemical coupling treatment system, and aquatic plants are planted. The photocatalytic ecological materials are used to decompose antibiotic molecules, and the aquatic plants are used to degrade pollutants.

[0010] To optimize the above technical solutions, the specific measures taken also include:

[0011] The aquaculture wastewater treatment system for synchronous removal of pollutants and antibiotics also includes a smart water system, which includes on-line water quality monitoring equipment, an aquaculture pond electric control pumping station, a treatment system electric control pumping station, electric control gates, inlet pipes, return pipes, recycling pipes, discharge pipes and an automatic control PLC system; the on-line water quality monitoring equipment is arranged at the end of the ecological-chemical coupling treatment system, the aquaculture pond electric control pumping station is arranged at the end of the aquaculture pond, the treatment system electric control pumping station is arranged at the end of the ecological-chemical coupling treatment system, the electric control gates are arranged at the ends of the ecological-physical coupling treatment system and the ecological treatment system, the inlet pipes connect the aquaculture pond, the ecological-physical coupling treatment system, the ecological treatment system and the ecological-chemical coupling treatment system, the return pipes are connected from the treatment system electric control pumping station to the ecological-physical coupling treatment system, the recycling pipes are connected from the treatment system electric control pumping station to the aquaculture pond, the discharge pipes are connected from the treatment system electric control pumping station to the receiving water body, and the automatic control PLC system is respectively connected with the on-line water quality monitoring equipment, the aquaculture pond electric control pumping station, the treatment system electric control pumping station and the electric control gates and controls the operation of the above equipment.

[0012] Both the ecological-physical coupling treatment system and the ecological treatment system adopt trapezoidal cross-sections, and the structural form adopts a soil pool wall. The soil pool wall is waterproofed with a geomembrane, the soil under the geomembrane is compacted, and planting soil is backfilled above the geomembrane.

[0013] Brush structures are suspended in the vertical direction of the water flow in the sedimentation unit. A number of wooden stakes are fixed in parallel on both sides of the sedimentation unit, with a spacing of 40-60 cm between the wooden stakes. A support rod is fixed at the top and bottom of the wooden stakes respectively, and the brush structure is vertically suspended between the upper and lower support rods.

[0014] Aeration discs are laid in the aeration unit, and a blower is connected to the aeration discs for aeration.

[0015] Aquatic plants are planted and aquatic animals are put in the ecological purification unit; the aquatic plants adopt emergent plants and submerged plants. The emergent plants include one or more of reed, loosestrife, cattail, common bulrush, and water shield, and the submerged plants include one or more of Najas minor, Potamogeton pectinatus, and Ceratophyllum demersum; the types of aquatic animals put in are fish and benthic animals. The fish include one or more of mullet and sea perch, and the benthic animals include one or more of hard clam and razor clam.

[0016] The precipitation unit is also provided with a precipitation cooperation structure. The precipitation cooperation structure includes an air pump, a precipitation cooperation air transmission pipe, a flocculant powder tank, a control valve and a number of spray heads. The brush structure includes a brush rod and bristles arranged on the brush rod. The brush rod is a hollow structure. The air pump is connected to the precipitation cooperation air transmission pipe, and the precipitation cooperation air transmission pipe is connected to the brush rod. The spray heads are distributed on the brush rod. The flocculant powder tank stores flocculant powder. The lower end of the flocculant powder tank is connected to the precipitation cooperation air transmission pipe through the control valve. When the control valve is opened, the flocculant powder can be quantitatively supplemented into the precipitation cooperation air transmission pipe. The air pump can inflate the brush rod of the brush structure through the precipitation cooperation air transmission pipe, so that the gas mixed with the flocculant powder is ejected from the spray heads.

[0017] The flocculant powder is FeCl3 powder admixed with diatomite.

[0018] The ecological treatment system adopts a trapezoidal cross-section, and the structural form adopts a mud pool wall. The construction area of the floating wetland is 40-50% of the water surface area of the ecological treatment system. It is fixed and suspended by connecting ropes and anchor blocks. The floating body material is polyester fiber, plant fiber composite material or modified plastic. The aquatic plants adopt emergent plants and submerged plants. The substrate layer adopts one or several of gravel, zeolite, ceramsite and volcanic rock. The roots of the emergent plants form a symbiotic system with the biofilm attached to the substrate layer. The biofilm includes nitrifying bacteria and denitrifying bacteria.

[0019] The ecological-chemical coupling treatment system uses photocatalytic ecological materials to oxidize and reduce organic pollutants, antibiotics and microorganisms in water under light. The layout area of the photocatalytic ecological materials is 30-40% of the water surface area. The photocatalytic ecological materials are of a mesh structure. The light-facing surface is the photocatalytic functional area, and the backlight-facing surface is the carrier functional area. The layout position is 10-15 cm below the water surface. The photocatalytic functional area is nano-titanium dioxide.

[0020] The method for treating aquaculture tail water for synchronously removing pollutants and antibiotics uses the above-mentioned aquaculture tail water treatment system for synchronously removing pollutants and antibiotics, and includes the following steps:

[0021] Step 1, the aquaculture pond discharges aquaculture tail water into the ecological-physical coupling treatment system through the aquaculture pond electric control pumping station. The precipitation unit removes suspended particulate matter in the water body; the aeration unit reduces the total phosphorus and permanganate index in the water body and provides oxygen for aquatic animals. By planting aquatic plants and stocking aquatic animals in the ecological purification unit, the nitrogen and phosphorus substances in the water body are transformed and the salinity of the water body is reduced; the ecological-physical coupling treatment system adopts multiple treatment areas for multi-stage gradient purification treatment;

[0022] Step 2: After meeting the residence time requirement of the ecological-physical coupling treatment system, the aquaculture tail water enters the ecological treatment system. The ecological treatment system adopts the microbial-plant collaborative degradation technology to degrade antibiotics by microorganisms. The roots of the emergent plants planted in the floating wetland serve as the places for microorganisms to inhabit, attach, and reproduce. Meanwhile, the aquatic plants in the floating wetland remove part of the antibiotics in the water body through the absorption process.

[0023] Step 3: After meeting the residence time requirement of the ecological treatment system, the aquaculture tail water enters the ecological-chemical coupling treatment system. The photocatalytic ecological material is driven by sunlight, and the pollutants and antibiotics in the water are decomposed through redox reactions, and the collaborative purification treatment is carried out with the aquatic plants.

[0024] Step 4: After meeting the residence time requirement of the ecological-chemical coupling treatment system, the conventional water quality indicators are detected by the on-line water quality monitoring equipment, and samples are taken for antibiotic detection. If the discharge standard is not met, it will enter the ecological-physical coupling treatment system again through the reflux pipeline by the electric control pump station of the treatment system, and the ecological purification process will be carried out cyclically until the discharge standard is met. If the discharge standard is met, according to whether recycling is needed, if recycling is needed, it will enter the aquaculture pond through the recycling pipeline by the electric control pump station of the treatment system, and if recycling is not needed, it will be discharged into the receiving water body through the discharge pipeline by the electric control pump station of the treatment system.

[0025] In Step 1, the specific steps for the precipitation unit to remove the suspended particulate matter in the water body are as follows: The air pump and the control valve are started regularly. When starting, the flocculant powder tank injects flocculant powder into the precipitation collaborative gas transmission pipe. The air pump sprays the air and the flocculant powder into the water body through the nozzle. While the flocculant powder forms flocs to absorb part of the antibiotics, part of the flocs hang on the bristles of the brush structure, forming an additional filter belt on the bristles to improve the efficiency of the bristles in filtering the suspended particulate matter.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] (1) The present invention proposes an aquaculture tail water treatment system and method for synchronously removing pollutants and antibiotics, which solves the problems of poor treatment efficiency of salinity and total nitrogen and the inability to remove antibiotics in the traditional aquaculture treatment technology.

[0028] (2) In the ecological-physical coupling treatment system of the present invention, multiple precipitation units are arranged at intervals. By arranging the precipitation units at intervals, the pollution particulate matter, sediment, etc. in the aquaculture tail water can be intercepted and precipitated under a smaller floor area, effectively reducing the concentration of suspended solids and organic matter in the influent water and reducing the pollution load of the subsequent treatment facilities.

[0029] (3) In the ecological-physical coupling treatment system of the present invention, multiple aeration units are arranged at intervals. By arranging the aeration zones at intervals, the effect of multi-stage aeration can be achieved with a relatively small floor area, and good removal effects on various pollutants can be obtained. At the same time, it can also provide good oxygen supply function for aquatic animals.

[0030] (4) Aquatic plants are planted in the ecological purification unit of the present invention. The selected submerged plants and emergent plants have relatively high salt tolerance thresholds and can survive under high salinity conditions. They can directly absorb available nutrients such as nitrogen and phosphorus in the water body through absorption and assimilation.

[0031] (5) Aquatic animals are put into the ecological purification unit of the present invention. Through the super-strong water filtration characteristics of mussels and the filtration and scraping characteristics of fish, the organic debris in the water body is filtered, purified and absorbed, the content of suspended solids in the water body is reduced, the water transparency is effectively improved, and the salinity in the water body is reduced.

[0032] (6) A floating wetland is constructed in the ecological treatment system of the present invention. The fillers of the floating wetland and the roots of the emergent plants are all important habitats, attachment and reproduction places for microorganisms. Microorganisms and plants cooperate to degrade pollutants in the water and degrade sulfamethoxazole in the water body.

[0033] (7) A photocatalytic ecological material is constructed in the ecological-chemical coupling treatment system of the present invention. The photocatalytic degradation mechanism is to use the holes and superoxide free radicals generated by absorbing light to oxidize the antibiotic organic molecules, destroy their structures, and cooperate with the plants to absorb antibiotics.

[0034] (8) The intelligent water service system of the present invention is equipped with an electronically controlled gate to ensure the hydraulic retention time of the aquaculture tail water and achieve sufficient purification treatment.

[0035] (9) A geomembrane is laid at the bottom of the treatment system of the present invention for anti-seepage, which can prevent the aquaculture tail water from seeping down to pollute the groundwater and the two-way exchange of groundwater and aquaculture tail water.

[0036] (10) The present invention is provided with a precipitation cooperation structure. The precipitation cooperation structure can spray air and flocculation powder into the water body through a nozzle. While the flocculation powder forms flocs to absorb part of the antibiotics, part of the flocs hang on the bristles of the brush structure, forming an additional filter belt on the bristles to improve the efficiency of the brush in filtering suspended particulate matter.

[0037] (11) The present invention is reasonably designed, easy to construct, and the later maintenance and management are electronically controlled and automated. It can bring great ecological benefits on the premise of minimizing the project investment, and has great reference significance for the treatment of aquaculture tail water. Description of the Drawings

[0038] Figure 1Schematic diagram of the aquaculture wastewater treatment system for synchronously removing pollutants and antibiotics in the present invention;

[0039] Figure 2 Flow chart of an ecological - physical and chemical coupling aquaculture wastewater treatment process for synchronously removing pollutants and antibiotics in the present invention;

[0040] Figure 3 Schematic diagram of the precipitation synergy structure;

[0041] Figure 4 is Figure 3 Enlarged view of the A - part structure of

[0042] In the figure: 1. Aquaculture pond; 2. Ecological - physical coupling treatment system; 3. Ecological treatment system; 4. Ecological - chemical coupling treatment system; 5. Intelligent water service system; 6. Precipitation unit; 7. Aeration unit; 8. Ecological purification unit; 9. Brush structure; 10. Aeration disk; 11. Emergent plants; 12. Submerged plants; 13. Fishes; 14. Benthic animals; 15. Floating wetland; 16. Photocatalytic ecological material; 17. Water quality on - line monitoring equipment; 18. Electric control pumping station of aquaculture pond; 19. Electric control pumping station of treatment system; 20. Electric control gate; 21. Inlet pipeline; 22. Return pipeline; 23. Recycling pipeline; 24. Discharge pipeline; 25. Receiving water body; 26. Air pump; 27. Precipitation synergy gas transmission pipe; 28. Flocculant powder tank; 29. Control valve; 30. Sprinkler head. Detailed implementation manners

[0043] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be described and explained below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application. Based on the embodiments provided by the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present application.

[0044] An aquaculture wastewater treatment system for synchronously removing pollutants and antibiotics, as Figure 1 shown, includes an aquaculture pond 1, an ecological - physical coupling treatment system 2, an ecological treatment system 3, an ecological - chemical coupling treatment system 4, and an intelligent water service system 5.

[0045] The ecological - physical coupling treatment system 2 is divided into three - level treatment areas, and each level of treatment area includes a precipitation unit 6, an aeration unit 7, and an ecological purification unit 8, constituting a three - level gradient ecological - physical coupling purification treatment.

[0046] The ecological-physical coupling treatment system 2 has a trapezoidal cross-section with a slope ratio of 1:0.5 to 1:1, a pool depth of 2 to 3 m, and a water depth of 1.5 to 2.5 m. The structure form uses a soil pool wall, and a geomembrane is used for anti-seepage under the soil pool wall. One-layer-one-membrane or two-layers-one-membrane is selected, with a specification of 300 - 500 g / m 2 , and the thickness is not less than 1.5 mm. The soil under the geomembrane is compacted, and 300 - 400 mm of planting soil is backfilled on the geomembrane.

[0047] In the sedimentation unit 6, a brush structure 9 is suspended in the vertical direction of the water flow near the drain outlet. The suspension position starts from near the drain outlet, and the length of the brush structure is 1 - 1.5 m. A number of wooden stakes are fixed in parallel on both sides of the sedimentation unit. The interval between the wooden stakes on the shore is 40 - 60 cm. One nylon rope is fixed at the top and bottom of the wooden stakes respectively, and then the brush structure is vertically suspended on the nylon rope, with 1 bundle suspended every 5 cm. The position of the wooden stakes should avoid the geomembrane; as Figure 3-4 shown, the sedimentation unit 6 is also provided with a sedimentation cooperation structure. The sedimentation cooperation structure includes an air pump 26, a sedimentation cooperation air pipe 27, a flocculant powder tank 28, a control valve 29, and a number of spray heads 30. The brush structure 9 includes a brush rod and bristles arranged on the brush rod. The brush rod is a hollow structure. The air pump 26 is connected to the sedimentation cooperation air pipe 27, and the sedimentation cooperation air pipe 27 is connected to the brush rod. The spray heads 30 are distributed on the brush rod. Flocculant powder is stored in the flocculant powder tank 28. The lower end of the flocculant powder tank 28 is connected to the sedimentation cooperation air pipe 27 through the control valve 29. When the control valve 29 is opened, the flocculant powder can be quantitatively supplemented into the sedimentation cooperation air pipe 27. The air pump 26 can inflate the brush rod of the brush structure 9 through the sedimentation cooperation air pipe 27, so that the gas mixed with the flocculant powder is ejected from the spray heads 30.

[0048] In the aeration unit 7, a nano-aeration disc is laid 20 - 40 cm away from the bottom of the pool, and a blower is set nearby. An aeration pipe is connected from the blower for aeration.

[0049] Aquatic plants are planted and aquatic animals are put in the ecological purification unit 8; the planting coverage of aquatic plants is 30 - 50%, and emergent plants 11 and submerged plants 12 are used. The planting density of emergent plants 11 is 10 - 25 plants / m 2 , including one or more of reed, loosestrife, cattail, bulrush, and floating heart. The planting density of submerged plants 12 is 10 - 20 plants / m 2 , including one or more of Najas minor, Potamogeton pectinatus, and Ceratophyllum demersum. The types of aquatic animals put in are fish 13 and benthic animals 14. The putting amount of fish 13 is 200 - 400 kg / mu, including one or more of mullet and sea perch. The putting amount of benthic animals 14 is 200 - 400 kg / mu, including one or more of Meretrix meretrix and Sinonovacula constricta.

[0050] The ecological treatment system 3 adopts the microbial-plant synergistic degradation technology. By utilizing the synergistic effect of specific microorganisms and aquatic plants, the antibiotic molecules are decomposed through microbial metabolism, and the root exudates of plants promote the degradation of pollutants.

[0051] The ecological treatment system 3 has a trapezoidal cross-section with a slope ratio of 1:0.5 to 1:1, a pond depth of 2 to 3 m, and a water depth of 1.5 to 2.5 m. The structure form uses a mud pool wall, and a geomembrane is used for anti-seepage under the mud pool wall. One-layer-one-membrane or two-layer-one-membrane is selected, with a specification of 300 to 500 g / m 2 , with a thickness of not less than 1.5 mm. The soil under the geomembrane is compacted, and 300 to 400 mm of planting soil is backfilled above the geomembrane.

[0052] A floating wetland 15 is constructed in the ecological treatment system, submerged plants 12 are planted, and aquatic animals are released.

[0053] The constructed area of the floating wetland 15 is 40 to 50% of the water surface area. It is fixed and suspended by connecting ropes and anchor blocks. The floating body material is polyester fiber, plant fiber composite material or modified plastic. The emergent plants planted are one or more of reed, loosestrife, cattail, water club-rush, and floating heart. The substrate layer is one or more of gravel, zeolite, ceramsite, and volcanic rock. The plant roots and the biofilm (including nitrifying bacteria, denitrifying bacteria, etc.) attached to the substrate form a symbiotic system, and the organic matter and antibiotics are decomposed through enzyme catalysis and mineralization.

[0054] The planting density of the submerged plants 12 is 10 to 20 plants / m 2 , including one or more of Najas minor, Potamogeton pectinatus, and Ceratophyllum demersum. The types of aquatic animals released are fish 13 and benthic animals 14. The release amount of fish 13 is 100 to 200 kg / mu, including one or more of mullet and sea perch. The release amount of benthic animals 14 is 100 to 200 kg / mu, including one or more of Meretrix meretrix and Sinonovacula constricta.

[0055] The ecological-chemical coupling treatment system 4 adopts the photocatalysis technology, combining ecological purification and chemical oxidation. By utilizing the photocatalytic activity of semiconductor materials, under light illumination, the organic pollutants, antibiotics, and microorganisms in water are decomposed into harmless substances through redox reactions. Through the complementarity and synergistic effect of ecological purification and chemical oxidation, efficient removal of pollutants and improvement of water quality are achieved;

[0056] The slope ratio of the ecological-chemical coupling treatment system 4 is 1:0.5 to 1:1, the pond depth is 2 to 3 m, and the water depth is 1.5 to 2.5 m. The structure form uses a mud pool wall, and a geomembrane is used for anti-seepage under the mud pool wall. One-layer-one-membrane or two-layer-one-membrane is selected, with a specification of 300 to 500 g / m 2 , with a thickness of not less than 1.5 mm. The soil under the geomembrane is compacted, and 300 to 400 mm of planting soil is backfilled above the geomembrane.

[0057] A photocatalytic ecological material 16 is arranged in the ecological-chemical coupling treatment system 4, and aquatic plants are planted.

[0058] The laying area of the photocatalytic ecological material 16 is 30-40% of the water surface area. The photocatalytic ecological material is of a net structure, with the light-facing side being the photocatalytic functional area and the backlight side being the carrier functional area. The laying position is 10-15 cm below the water surface.

[0059] The planting coverage of the aquatic plants is 20-30%. Emergent plants 11 and submerged plants 12 are used. The planting density of the emergent plants 11 is 10-25 plants / m 2 , including one or more of reed, loosestrife, cattail, softstem bulrush, and floating heart; the planting density of the submerged plants 12 is 10-20 plants / m 2 , including one or more of Najas minor, Potamogeton pectinatus, and Ceratophyllum demersum.

[0060] Furthermore, the intelligent water service system 5 includes an on-line water quality monitoring device 17, an electro-control pumping station 18 for the aquaculture pond, an electro-control pumping station 19 for the treatment system, an electro-control gate 20, a water inlet pipe 21, a reflux pipe 22, a recycling pipe 23, a discharge pipe 24, and an automatic control PLC system connecting between the devices.

[0061] The on-line water quality monitoring device 17 is arranged at the end of the ecological-chemical coupling treatment system 2. The electro-control pumping station 18 for aquaculture is arranged at the end of each breeding area of the aquaculture pond 1. The electro-control pumping station 19 for the treatment system is arranged at the end of the ecological-chemical coupling treatment system 2. The electro-control gate 20 is arranged at the ends of the ecological-physical coupling treatment system 2 and the ecological treatment system 3. The water inlet pipe 21 connects the aquaculture pond 1, the ecological-physical coupling treatment system 2, the ecological treatment system 3, and the ecological-chemical coupling treatment system 4. The reflux pipe 22 is connected from the electro-control pumping station 19 of the treatment system to the ecological-physical coupling treatment system 2. The recycling pipe 23 is connected from the electro-control pumping station 19 of the treatment system to the aquaculture pond 1. The discharge pipe 24 is connected from the electro-control pumping station of the treatment system to the receiving water body 25.

[0062] An ecological-physical multiple coupling aquaculture tail water treatment process for synchronously removing pollutants and antibiotics, the steps of which are as follows:

[0063] Step 1: The aquaculture pond 1 discharges aquaculture tail water through the electric control pump station 18 and enters the ecological-physical coupling treatment system 2 through the water inlet pipe 21. At this stage, the aquaculture tail water needs to stay in the pond for 15 - 20 days (in summer) and 25 - 30 days (in spring and autumn) for water quality purification treatment. The sedimentation unit 6 serves as the core of pretreatment, and larger suspended particles are removed through the sedimentation unit 6. The air pump 26 and the control valve 29 are started once every two days, and the injection amount into the water body each time is 5 - 20 g of FeCl3 powder mixed with diatomaceous earth per ton of water. The FeCl3 powder is used to produce a flocculation effect, and the diatomaceous earth is used to prevent the FeCl3 powder from aggregating into clusters. When the flocculant powder forms flocs that absorb some antibiotics, some flocs hang on the bristles of the brush structure 9, forming an additional filter belt on the bristles to improve the efficiency of the bristles in filtering suspended particles.

[0064] The aeration unit 7 and the ecological purification unit 8 work together. The aeration unit 7 reduces indicators such as total phosphorus and permanganate index in the tail water and can provide oxygen for aquatic animals. By planting aquatic plants and stocking aquatic animals in the ecological purification unit 8, substances such as nitrogen and phosphorus in the water body are transformed, and the salinity of the tail water is reduced. To ensure the water quality purification effect, the ecological-physical coupling treatment system 2 adopts a three-stage treatment area for multi-stage gradient purification treatment, and the system has a stronger resistance to the impact load of tail water.

[0065] Step 2: After meeting the residence time requirement of the ecological-physical coupling treatment system 2, open the electric control gate 20, and the aquaculture tail water enters the ecological treatment system 3 through the water inlet pipe 21. At this stage, the aquaculture tail water needs to stay in the pond for 5 - 10 days (in summer) and 10 - 15 days (in spring and autumn) for water quality purification treatment. The ecological treatment system 3 adopts the technology of microbial-plant synergistic degradation. The removal of pollutants by microorganisms is mainly completed by their own uptake and biodegradation of pollutants. Aerobic microorganisms, some anaerobic and facultative anaerobic microorganisms can all degrade sulfamethoxazole. The roots of the emergent plants planted in the floating wetland 15 are important habitats, attachment and reproduction places for microorganisms. At the same time, aquatic plants can also remove some antibiotics in the water body through the absorption process.

[0066] Step 3: After meeting the residence time requirement of the ecological treatment system 3, open the electric control gate 20, and the aquaculture tail water enters the ecological-chemical coupling treatment system 4 through the water inlet pipe 21. At this stage, the aquaculture tail water needs to stay in the pond for 5 - 10 days (in summer) and 10 - 15 days (in spring and autumn) for water quality purification treatment. The photocatalytic ecological material 16 is driven by sunlight. Using the photocatalytic activity of semiconductor materials, pollutants and antibiotics in the water are decomposed through redox reactions under light, and synergistic purification treatment is carried out with aquatic plants.

[0067] Step 4, after meeting the residence time requirement of the ecological-chemical coupling treatment system 4, detect the conventional water quality indicators through the on-line water quality monitoring equipment 17 and take samples for antibiotic detection; if the discharge standard is not met, enter the reflux pipeline 22 through the treatment system electric control pumping station 19 and enter the ecological-physical coupling treatment system 2 again to circulate the ecological purification process until the discharge standard is met; if the discharge standard is met, according to whether recycling is needed, if recycling is needed, enter the aquaculture pond through the treatment system electric control pumping station 19 and enter the recycling pipeline 23, if recycling is not needed, enter the discharge pipeline 24 through the treatment system electric control pumping station 19 and discharge it into the receiving water body 25.

[0068] The following gives two specific embodiments to elaborate in detail an ecological-physical and chemical multiple coupling aquaculture tail water treatment process for synchronously removing pollutants and antibiotics:

[0069] Embodiment 1

[0070] Treat the tail water of an aquaculture pond in a certain place in Jiangsu. Embodiment 1 of this application proposes an aquaculture tail water treatment system and method for synchronously removing pollutants and antibiotics. The total area of the aquaculture pond 1 in this place is about 180,000 m 2 , according to Figure 1 , Figure 2 Design an aquaculture tail water treatment system, in which the area of the ecological-physical coupling treatment 2 system is about 8000 m 2 , the area of the ecological treatment system 3 is about 5000 m 2 , and the area of the ecological-chemical coupling treatment system 4 is about 5000 m 2 .

[0071] The ecological-physical coupling treatment system 2 adopts a trapezoidal cross-section, the slope ratio is 1:1, the pool depth is 2.5 m, and the water depth is 2 m; the structural form adopts a soil pool wall, and a geomembrane is used for anti-seepage under the soil pool wall. Two-layer geotextile and one-layer geomembrane are selected, with a specification of 500 g / m 2 , a thickness of 2 mm, the soil under the geomembrane is tamped, and 350 mm of planting soil is backfilled above the geomembrane;

[0072] In the sedimentation unit 6, a brush structure 9 is suspended in the vertical direction of the water flow near the drainage outlet. The suspension position starts from near the drainage outlet, the length of the brush structure is 1 m, and several wooden piles are fixed in parallel on both sides of the sedimentation unit. The interval between the wooden piles on the shore is 40 cm. One nylon rope is fixed at the top and bottom of the wooden piles respectively, and then the brush structure is vertically suspended on the nylon rope, with 1 bundle suspended every 5 cm. The position of the wooden piles should avoid the geomembrane;

[0073] In the aeration unit 7, a nano-aeration disk is laid 40 cm from the bottom of the pool, and a blower is set nearby. An aeration pipe is connected from the blower for aeration;

[0074] Aquatic plants are planted in the ecological purification unit 8, and aquatic animals are released; the coverage of aquatic plants is 30%, and emergent plants 11 and submerged plants 12 are used. The planting density of emergent plants 11 is 20 plants / m 2 , including reeds and loosestrife, submerged plants 12 planting density of 10 to 20 plants / m 2 , including comb-toothed pondweed and duckweed; the aquatic animal species released are 13 fish and 14 benthic animals, the fish release rate 13 is 400kg / mu, including mullet and pike, and the benthic animal release rate 14 is 300kg / mu, including clams and razor clams.

[0075] Ecological treatment system 3 adopts a trapezoidal cross-section with a slope ratio of 1:1, a pool depth of 2.5m, and a water depth of 2m. The structure adopts an earth pool wall, and a geomembrane is used under the earth pool wall for anti-seepage. The two-cloth and one-membrane are selected, and the specification is 500g / m 2 , the thickness is 2mm, the soil under the geomembrane is compacted, and 350mm of planting soil is backfilled on the geomembrane;

[0076] The floating wetland 15 covers an area of 40% of the water surface area and is suspended using connecting ropes and anchor blocks. The floating material is polyester fiber, and the emergent plants planted are cattail, water plantain and water hyacinth. The substrate layer is gravel and zeolite.

[0077] Submerged plants 12 planting density is 20 plants / m 2 , including comb-toothed pondweed and duckweed; the aquatic animals released are 13 fish and 14 benthic animals, the release amount of fish 13 is 150kg / mu, and the fish is mullet; the release amount of benthic animals 14 is 200kg / mu, and the benthic animals are clams.

[0078] The slope ratio of the ecological-chemical coupling treatment system 4 is 1:0.5, the pool depth is 2m, and the water depth is 1.5m. The structure adopts mud pool wall, and geomembrane is used under the mud pool wall for anti-seepage. The selection is one cloth and one membrane, with a specification of 300g / m 2 , the thickness is 1.5mm, the soil under the geomembrane is compacted, and 300mm of planting soil is backfilled on the geomembrane;

[0079] The photocatalytic ecological material 16 is laid out in an area of 40% of the water surface area. The photocatalytic ecological material has a mesh structure, with the light-facing side being the photocatalytic functional area and the backlight side being the carrier functional area. The layout position is 10 cm below the water surface.

[0080] The coverage of aquatic plants is 25%, with 11 emergent plants and 12 submerged plants. The planting density of emergent plants 11 is 25 plants / m 2 , including reeds, loosestrife, cattails and water plantains; submerged plants 12 are planted at a density of 20 plants / m 2 , including small algae and comb-toothed pondweed.

[0081] The intelligent water service system 5 includes an on-line water quality monitoring device 17, an electro-control pump station 18 for aquaculture ponds, an electro-control pump station 19 for the treatment system, an electro-control gate 20, a water inlet pipe 21, a return pipe 22, a recycling pipe 23, a discharge pipe 24, and an automatic control PLC system connected between the devices.

[0082] The on-line water quality monitoring device 17 is arranged at the end of the ecological-chemical coupling treatment system 2. The electro-control pump station 18 for aquaculture is arranged at the end of each aquaculture area of the aquaculture pond 1. The electro-control pump station 19 for the treatment system is arranged at the end of the ecological-chemical coupling treatment system 2. The electro-control gate 20 is arranged at the ends of the ecological-physical coupling treatment system 2 and the ecological treatment system 3. The water inlet pipe 21 connects the aquaculture pond 1, the ecological-physical coupling treatment system 2, the ecological treatment system 3, and the ecological-chemical coupling treatment system 4. The return pipe 22 is connected from the electro-control pump station 19 for the treatment system to the ecological-physical coupling treatment system 2. The recycling pipe 23 is connected from the electro-control pump station 19 for the treatment system to the aquaculture pond 1. The discharge pipe 24 is connected from the electro-control pump station for the treatment system to the receiving water body 25.

[0083] In this embodiment 1, an ecological-physical multiple coupling aquaculture tail water treatment process for synchronously removing pollutants and antibiotics comprises the following steps:

[0084] Step 1: The aquaculture pond 1 discharges aquaculture tail water through the electro-control pump station 18 for aquaculture ponds and enters the ecological-physical coupling treatment system 3 through the water inlet pipe 21. In this stage, the aquaculture tail water needs to stay in the pond for 25 days (in summer) and 35 days (in spring and autumn) for water quality purification treatment. The sedimentation unit 6 serves as the core of pretreatment to remove larger suspended particles through the sedimentation unit 6. The aeration unit 7 and the ecological purification unit 8 act synergistically. The aeration unit 7 reduces indexes such as total phosphorus and permanganate index in the tail water and can provide oxygen for aquatic animals. By planting aquatic plants and stocking aquatic animals in the ecological purification unit 8, substances such as nitrogen and phosphorus in the water body are converted, and the salinity in the tail water is reduced. To ensure the water quality purification effect, the ecological-physical coupling treatment system 2 adopts three treatment areas for multi-stage gradient purification treatment, and the system has stronger resistance to the impact load of tail water.

[0085] Step 2: After meeting the residence time requirement of the ecological-physical coupling treatment system 2, open the electric control gate 20, and the aquaculture tail water enters the ecological treatment system 3 through the water inlet pipe 21. At this stage, the aquaculture tail water needs to stay in the pond for 10 days (in summer) and 12 days (in spring and autumn) for water quality purification treatment. The ecological treatment system 3 adopts the microbial-plant synergistic degradation technology. The removal of pollutants by microorganisms is mainly completed by their own uptake and biodegradation of pollutants. Aerobic microorganisms, some anaerobic and facultative anaerobic microorganisms can all degrade sulfamethoxazole. The roots of the emergent plants planted in the floating wetland 15 are important habitats, attachment and reproduction places for microorganisms. At the same time, aquatic plants can also remove some antibiotics in the water through the absorption process.

[0086] Step 3: After meeting the residence time requirement of the ecological treatment system 3, open the electric control gate 20, and the aquaculture tail water enters the ecological-chemical coupling treatment system 4 through the water inlet pipe 21. At this stage, the aquaculture tail water needs to stay in the pond for 5 days (in summer) and 10 days (in spring and autumn) for water quality purification treatment. Drive the photocatalytic ecological material 16 by sunlight, utilize the photocatalytic activity of the semiconductor material, and decompose the pollutants and antibiotics in the water through redox reactions under light, and carry out synergistic purification treatment with aquatic plants.

[0087] Step 4: After meeting the residence time requirement of the ecological-chemical coupling treatment system 4, detect the conventional water quality indicators through the water quality on-line monitoring device 17 and take samples for antibiotic detection.

[0088] Step 5: According to the requirements of Article 4.2 of the Jiangsu Provincial Local Standard "Discharge Standard of Aquaculture Tail Water in Ponds" (DB32 / 4043-2021), the distinction between the fresh water area and the sea water area of the sea-going rivers involved is defined by the tide gate. The water area above the tide gate belongs to the fresh water area, and the water area below the tide gate belongs to the sea water area. For the sea-going rivers without tide gates, the coastline is used for definition. The water area above the coastline belongs to the fresh water area, and the water area below the coastline belongs to the sea water area. The receiving water body 25 is a fresh water area above the tide gate, and the designed effluent water quality standard is implemented according to the secondary standard of the aquaculture discharge limit for fresh water receiving waters.

[0089] According to the effluent detection results, after being purified by the treatment system, the salinity, suspended solids, total nitrogen, total phosphorus, and permanganate index of the aquaculture tail water can all meet the requirements of the secondary standard of the Jiangsu Provincial Local Standard "Discharge Standard of Aquaculture Tail Water in Ponds" (DB32 / 4043-2021). The removal rate of florfenicol is 93.2%, and the removal rate of sulfamethoxazole is 88.7%. The antibiotic removal rate is relatively high. The effluent of this aquaculture tail water does not need to be recycled, and the electric control pump station 19 of the treatment system enters the discharge pipe 24 and is discharged into the receiving water body 25.

[0090] Table 1 Water quality test indexes of the influent and effluent of the tail water from an aquaculture pond in a certain place in Jiangsu in Example 1

[0091]

[0092]

[0093] Example 2

[0094] The tail water of an aquaculture pond in a certain place in Hunan is treated. In this Example 2, an aquaculture tail water treatment system and method for synchronously removing pollutants and antibiotics are proposed. The total area of the aquaculture pond 1 in this place is about 70,000 m 2 , according to Figure 1 、 Figure 2 design an aquaculture tail water treatment system, in which the area of the ecological-physical coupling treatment 2 system is about 3000 m 2 , the area of the ecological treatment system 3 is about 2000 m 2 , and the area of the ecological-chemical coupling treatment system 4 is about 2000 m 2 . The treatment system in Example 2 is basically the same as that in Example 1, with some parameters being different.

[0095] The slope ratio of the ecological-physical coupling treatment system 2 is 1:0.8, the pool depth is 2.3 m, and the water depth is 1.8 m; the geomembrane is a one-layer and one-membrane type, with a specification of 400 g / m 2 , a thickness of 1.8 mm, and 400 mm of planting soil is backfilled on the geomembrane;

[0096] The brush structure length of the sedimentation unit 6 is 1 m, and the shore wooden stakes are spaced 40 cm apart;

[0097] The aeration unit 7 lays a nano-aeration disc 20 cm from the bottom of the pool;

[0098] The coverage of aquatic plant planting in the ecological purification unit 8 is 45%, the planting density of emergent plants 11 is 15 plants / m 2 , including cattail and common bulrush, and the planting density of submerged plants 12 is 20 plants / m 2 , including Najas minor and Potamogeton pectinatus; the fish stocking rate 13 is 300 kg / mu, the fish is mullet, and the stocking rate of benthic animals 14 is 250 kg / mu, and the benthic animal is razor clam.

[0099] The slope ratio of the ecological treatment system 3 is 1:0.8, the pool depth is 2.3 m, and the water depth is 1.8 m; the geomembrane is a one-layer and one-membrane type, with a specification of 400 g / m 2 , a thickness of 1.8 mm, and 400 mm of planting soil is backfilled on the geomembrane;

[0100] The construction area of floating wetland 15 is 50% of the water surface area. The floating material is plant fiber composite material, and the emergent plants planted are loosestrife and cattail. The substrate layer is made of ceramsite and volcanic rock.

[0101] Submerged plants 12 planting density is 20 plants / m 2 , including comb-toothed pondweed and duckweed; the release amount of fish 13 is 150kg / mu, and the fish is mullet; the release amount of benthic animals 14 is 200kg / mu, and the benthic animals are razor clams.

[0102] The slope ratio of the ecological-chemical coupling treatment system 4 is 1:0.8, the pool depth is 2.1m, and the water depth is 1.6m; the geomembrane uses one cloth and one membrane, with a specification of 400g / m 2 , the thickness is 1.8mm, and 400mm of planting soil is backfilled on the geomembrane;

[0103] The photocatalytic ecological material 16 is laid out in an area of 30% of the water surface area and is laid out at a position 15 cm below the water surface;

[0104] The coverage of aquatic plants is 30%, and the planting density of emergent plants is 15 plants / m 2 , including reed, loosestrife, water plantain and water nymph; submerged plants 12 planting density is 10 plants / m 2 , including small algae and duckweed.

[0105] The composition and arrangement of the smart water system 5 of Example 2 are basically the same as those of Example 1.

[0106] In this embodiment 2, an ecological, physical and chemical coupled aquaculture tailwater treatment process for simultaneously removing pollutants and antibiotics is provided. The treatment system of embodiment 2 is basically the same as that of embodiment 1, with some parameters being different. The steps are as follows:

[0107] Step 1: The aquaculture tailwater needs to stay in the ecological-physical coupling treatment system 3 for 16 days (in summer) and 25 days (in spring and autumn) for water purification;

[0108] Step 2: The aquaculture tail water needs to stay in the ecological treatment system 3 for 6 days (in summer) and 11 days (in spring and autumn) for water purification;

[0109] Step 3: The aquaculture tailwater needs to stay in the ecological-chemical coupling treatment system 4 for 5 days (in summer) and 10 days (in spring and autumn) for water purification;

[0110] Step 4: After the residence time requirements of the eco-chemical coupling treatment system 4 are met, conventional water quality indicators are tested using the online water quality monitoring equipment 17, and samples are taken for antibiotic testing;

[0111] Step 5: According to the requirements of Article 4.2 of the Hunan Local Standard "Discharge Standard for Pollutants in Aquaculture Tailwater" (DB43 / 1752-2020), the key protection waters refer to the surface water class III functional waters in GB3838 (except for the designated drinking water source protection areas), and the aquaculture tailwater discharged into these waters shall comply with the first-class standard; the general waters refer to the surface water class I and V functional waters in GB3838 and other waters with undefined environmental functions, and the aquaculture tailwater discharged into these waters shall comply with the second-class standard. This receiving water body 25 belongs to the general waters, and the designed effluent water quality standard shall be implemented according to the second-class standard of the discharge limit of pollutants in aquaculture tailwater;

[0112] According to the effluent detection results, after being purified by the treatment system, the suspended solids, total nitrogen, total phosphorus, and permanganate index of the aquaculture tailwater can all meet the requirements of the second-class standard of the Hunan Local Standard "Discharge Standard for Pollutants in Aquaculture Tailwater" (DB43 / 1752-2020). This standard has no requirement for salinity, and the salinity removal rate in this case is 92.8%; the removal rate of florfenicol is 92.2%, and the removal rate of sulfamethoxazole is 87.6%, with a relatively high removal rate of antibiotics. The effluent of this aquaculture tailwater needs to be recycled, and the electric control pumping station 19 of the treatment system enters the discharge pipeline 23 and is discharged into the aquaculture pond 1.

[0113] Table 2 shows the test index conditions of the influent and effluent water quality of the tailwater of an aquaculture pond in a certain place in Hunan in Example 2

[0114]

[0115] The above embodiments are the preferred embodiments of the present invention, but the embodiments of the present invention are not limited by the described embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. Aquaculture wastewater treatment system for synchronously removing pollutants and antibiotics, characterized in that, It includes an aquaculture pond (1), an ecological-physical coupling treatment system (2), an ecological treatment system (3), and an ecological-chemical coupling treatment system (4). In the ecological-physical coupling treatment system (2), multiple levels of series-connected treatment areas are divided. Each level of treatment area includes a series-connected sedimentation unit (6), an aeration unit (7), and an ecological purification unit (8), constituting a three-level gradient ecological-physical coupling purification treatment. The sedimentation unit (6) is used to remove larger suspended particulate matters in the water body. The aeration unit (7) is used to aerate the water body, reduce the total phosphorus and permanganate index in the water body, and provide oxygen for aquatic animals. The ecological purification unit (8) plants aquatic plants and releases aquatic animals. The aquatic plants and aquatic animals are used to convert nitrogen and phosphorus in the water body and reduce the salinity of the water body. In the ecological treatment system (3), a floating wetland is constructed, aquatic plants are planted, and microorganisms are put in. The microorganisms and the aquatic plants synergistically metabolize and decompose antibiotic molecules and degrade pollutants. In the ecological-chemical coupling treatment system (4), photocatalytic ecological materials (16) are arranged and aquatic plants are planted. The photocatalytic ecological materials (16) are used to decompose antibiotic molecules, and the aquatic plants are used to degrade pollutants.

2. The aquaculture tail water treatment system for synchronously removing pollutants and antibiotics according to claim 1, wherein It also includes an intelligent water service system (5). The intelligent water service system (5) includes an online water quality monitoring device (17), an aquaculture pond electric control pumping station (18), a treatment system electric control pumping station (19), an electric control gate (20), a water inlet pipe (21), a reflux pipe (22), a recycling pipe (23), a discharge pipe (24), and an automatic control PLC system. The online water quality monitoring device (17) is arranged at the end of the ecological-chemical coupling treatment system (4). The aquaculture pond electric control pumping station (18) is arranged at the end of the aquaculture pond (1). The treatment system electric control pumping station (19) is arranged at the end of the ecological-chemical coupling treatment system (4). The electric control gate (20) is arranged at the ends of the ecological-physical coupling treatment system (2) and the ecological treatment system (3). The water inlet pipe (21) connects the aquaculture pond (1), the ecological-physical coupling treatment system (2), the ecological treatment system (3), and the ecological-chemical coupling treatment system (4). The reflux pipe (22) is connected from the treatment system electric control pumping station (19) to the ecological-physical coupling treatment system (2). The recycling pipe (23) is connected from the treatment system electric control pumping station (19) to the aquaculture pond (1). The discharge pipe (24) is connected from the treatment system electric control pumping station to the receiving water body (25). The automatic control PLC system is respectively connected to the online water quality monitoring device (17), the aquaculture pond electric control pumping station (18), the treatment system electric control pumping station (19), and the electric control gate (20) and controls the operation of the above devices.

3. The aquaculture wastewater treatment system for synchronously removing pollutants and antibiotics according to claim 1, characterized in that, Both the ecological-physical coupling treatment system (2) and the ecological treatment system (3) adopt a trapezoidal cross-section. The structural form uses a soil pool wall. The soil pool wall is waterproofed with a geomembrane at the bottom. The soil under the geomembrane is tamped, and planting soil is backfilled on the geomembrane.

4. The aquaculture wastewater treatment system for synchronously removing pollutants and antibiotics according to claim 1, wherein The sedimentation unit (6) is provided with a brush structure (9) suspended in a direction perpendicular to the water flow. A plurality of wooden stakes are fixed in parallel on both sides of the sedimentation unit, with the wooden stakes spaced 40 to 60 cm apart. A support rod is fixed on the top and bottom of the wooden stakes, respectively. The brush structure (9) is vertically suspended between the upper and lower support rods. An aeration plate (10) is laid in the aeration unit (7), and a blower is connected to the aeration plate (10) for aeration; Aquatic plants are planted in the ecological purification unit (8), and aquatic animals are placed. The aquatic plants include emergent plants (11) and submerged plants (12). The emergent plants (11) include one or more of reed, loosestrife, cattail, water plantain, and water nymph. The submerged plants (12) include one or more of small algae, comb-toothed pondweed, and golden duckweed. The aquatic animals placed are fish (13) and benthic animals (14). The fish (13) include one or more of mullet and pike. The benthic animals (14) include one or more of clam and razor clam.

5. The aquaculture wastewater treatment system for synchronously removing pollutants and antibiotics according to claim 4, characterized in that, The sedimentation unit (6) is also provided with a sedimentation cooperative structure, which includes an air pump (26), a sedimentation cooperative air supply pipe (27), a flocculation powder tank (28), a control valve (29) and a plurality of nozzles (30). The brush structure (9) includes a brush rod and bristles arranged on the brush rod, and the brush rod is a hollow structure. The air pump (26) is connected to the sedimentation cooperative air supply pipe (27), and the sedimentation cooperative air supply pipe (27) is connected to the brush rod. The nozzles (30) are distributed on the brush rod. Flocculation powder is stored in the flocculation powder tank (28). The lower end of the flocculation powder tank (28) is connected to the sedimentation cooperative air supply pipe (27) through the control valve (29). When the control valve (29) is opened, flocculation powder can be quantitatively added to the sedimentation cooperative air supply pipe (27). The air pump (26) can inflate the brush rod of the brush structure (9) through the sedimentation cooperative air supply pipe (27), so that the gas mixed with flocculation powder is ejected from the nozzle (30).

6. The aquaculture tail water treatment system for synchronously removing pollutants and antibiotics according to claim 5, wherein The flocculating powder is FeCl3 powder mixed with diatomaceous earth.

7. The aquaculture tail water treatment system for synchronously removing pollutants and antibiotics according to claim 5, wherein, The ecological treatment system (3) adopts a trapezoidal cross-section and a mud pool wall as a structural form. The construction area of the floating wetland (15) is 40 to 50% of the water surface area of the ecological treatment system (3). It is fixed and suspended by connecting ropes and anchor blocks. The floating material is polyester fiber, plant fiber composite material or modified plastic. The aquatic plants adopt emergent plants (11) and submerged plants (12). The matrix layer adopts one or more of gravel, zeolite, ceramsite and volcanic rock. The roots of the emergent plants form a symbiotic system with the biofilm attached to the matrix layer. The biofilm includes nitrifying bacteria and denitrifying bacteria.

8. The aquaculture tail water treatment system for synchronously removing pollutants and antibiotics according to claim 5, characterized in that, The ecological-chemical coupling treatment system (4) adopts photocatalytic ecological materials (16) to reduce organic pollutants, antibiotics and microorganisms in water through redox reactions under light. The layout area of the photocatalytic ecological materials (16) is 30-40% of the water surface area. The photocatalytic ecological materials (16) are of a mesh structure, the light-facing side is a photocatalytic functional area, and the backlight side is a carrier functional area. The layout position is 10-15 cm below the water surface, and the photocatalytic functional area is nano-titanium dioxide.

9. Aquaculture wastewater treatment method for synchronously removing pollutants and antibiotics, applying the aquaculture wastewater treatment system for synchronously removing pollutants and antibiotics as described in claim 5, characterized in that, The following steps are involved: Step 1: The aquaculture pond (1) discharges aquaculture tail water into the ecological-physical coupling treatment system (2) through the aquaculture pond electric control pumping station (18). The sedimentation unit (6) removes suspended particulate matter in the water body. The aeration unit (7) reduces the total phosphorus and permanganate index in the water body and provides oxygen for aquatic animals. By planting aquatic plants and releasing aquatic animals in the ecological purification unit (8), the nitrogen and phosphorus substances in the water body are transformed, and the salinity of the water body is reduced. The ecological-physical coupling treatment system (2) adopts multiple treatment areas for multi-level gradient purification treatment. Step 2: After meeting the residence time requirement of the ecological-physical coupling treatment system (2), the aquaculture tail water enters the ecological treatment system (3). The ecological treatment system (3) adopts the microbial-plant synergistic degradation technology to degrade antibiotics by microorganisms. The roots of the emergent plants planted in the floating wetland (15) serve as the place for microorganisms to inhabit, attach and reproduce. At the same time, the aquatic plants in the floating wetland (15) remove part of the antibiotics in the water body through the absorption process. Step 3: After meeting the residence time requirement of the ecological treatment system (3), the aquaculture tail water enters the ecological-chemical coupling treatment system (4). The photocatalytic ecological material (16) is driven by sunlight, and the pollutants and antibiotics in the water are decomposed through redox reactions and synergistically purified with aquatic plants. Step 4: After meeting the residence time requirement of the ecological-chemical coupling treatment system (4), the conventional water quality indicators are detected by the water quality on-line monitoring equipment (17), and samples are taken for antibiotic detection. If the discharge standard is not met, it will enter the ecological-physical coupling treatment system (2) again through the reflux pipeline (22) by the treatment system electric control pumping station (19), and the ecological purification process will be carried out cyclically until the discharge standard is met. If the discharge standard is met, according to whether recycling is needed, if recycling is needed, it will enter the aquaculture pond through the recycling pipeline (23) by the treatment system electric control pumping station (19). If recycling is not needed, it will be discharged into the receiving water body (25) through the discharge pipeline (24) by the treatment system electric control pumping station (19).

10. The aquaculture tail water treatment method for synchronously removing pollutants and antibiotics according to claim 9, characterized in that, In Step 1, the specific steps for the sedimentation unit (6) to remove suspended particulate matter in the water body are as follows: The air pump (26) and the control valve (29) are started regularly. When starting, the flocculant powder tank (28) injects flocculant powder into the sedimentation co-transmission air pipe (27). The air pump (26) sprays the air and flocculant powder into the water body through the nozzle (30). While the flocculant powder forms flocs to absorb part of the antibiotics, some flocs hang on the bristles of the brush structure (9), forming an additional filter belt on the bristles to improve the efficiency of the bristles in filtering suspended particulate matter.

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