Low-carbon efficient mariculture wastewater treatment device and method

Abstract

The application discloses a low-carbon and high-efficiency seawater breeding wastewater treatment device and method, wherein the device comprises a sequencing batch reactor and a modified hollow fiber membrane assembly arranged in the sequencing batch reactor, and is provided with a stirring, constant temperature, monitoring and aeration control unit. The method strengthens the microbial biofilm by the modified membrane assembly, adopts a salinity and antibiotic gradient domestication strategy, constructs a stable simultaneous nitrification and denitrification (SND) process under a low dissolved oxygen (DO<0.2 mg / L) condition, and realizes efficient and collaborative removal of carbon, nitrogen pollutants and antibiotics. The application significantly improves the stability of the system against salinity and antibiotic impact, reduces the aeration energy consumption, effectively solves the problem that the microbial activity is inhibited when the traditional biological process is used to treat high-salinity and antibiotic-containing seawater breeding wastewater, and provides a reliable technical scheme for low-carbon and high-efficiency treatment of seawater breeding wastewater.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, specifically to a low-carbon and high-efficiency marine aquaculture wastewater treatment device and method, applicable to marine aquaculture wastewater treatment. Background Technology

[0002] Effective removal of nitrogen pollutants from aquaculture wastewater is an urgent environmental need.

[0003] In intensive marine aquaculture, antibiotics (including sulfonamides (SAs), fluoroquinolones (FQs), tetracyclines (TCs), and macrolides (MAs)) are widely used for disease prevention and treatment. However, due to low antibiotic utilization rates, residual drugs are eventually released into surrounding waters or enter sediments in aquaculture areas, continuing to spread and causing ecological risks such as marine environmental pollution and the migration of resistance genes. While some physicochemical technologies based on membrane separation and advanced oxidation have been explored for antibiotic removal with the goal of water recycling, technical bottlenecks such as unstable treatment efficiency and high energy consumption remain.

[0004] Currently, relatively mature technologies for treating marine aquaculture wastewater, primarily based on biological treatment processes, have been developed. Traditional biological nitrogen removal processes typically involve two independent processes: nitrification and denitrification. Nitrification, under aerobic conditions, removes ammonia nitrogen (NH4+). + -N) is oxidized to nitrate nitrogen (NO3). - (NO3-N), while denitrification, under anaerobic conditions, utilizes microbial activity to convert NO3- into nitrogen. - -N is reduced to nitrogen (N2). Although this process is effective, traditional methods often involve high energy consumption and the input of external carbon sources while achieving water purification. In addition, the high salinity of seawater and the inhibitory effect of residual antibiotics on microbial activity are key challenges restricting the application of biological treatment technology in marine aquaculture wastewater treatment projects.

[0005] Simultaneous nitrification-denitrification (SND) technology based on membrane aerated biofilm reactors (MABR) is a novel and highly efficient biological nitrogen removal technology. It utilizes a hydrophobic, permeable membrane to supply oxygen to microorganisms, improving oxygen mass transfer efficiency and reducing energy costs. SND combines nitrification and denitrification in a single reactor under limited dissolved oxygen conditions, representing an effective improvement over traditional biological nitrogen removal technologies. SND technology has lower space and operational requirements, as well as relatively lower construction and operating costs. Compared to traditional biological nitrogen removal technologies, SND technology can reduce sludge production and adapt to different influent water quality variations. MABR is a novel oxygen transfer technology that uses a hydrophobic, permeable hollow fiber membrane immersed in the biological treatment system. On one hand, MABR provides the necessary oxygen to microorganisms through bubble-free aeration, achieving green and low-energy consumption. On the other hand, the heterogeneous mass transfer characteristics of MABR can form a unique microbial stratification structure, facilitating relatively independent control during operation, maintaining microbial abundance and activity, and achieving good synergistic growth effects among different microorganisms. MABR (Multi-Activated Biofilm Reactor) facilitates the construction of efficient simultaneous nitrification and denitrification processes, enabling low-carbon, nitrogen-containing wastewater to break free from dependence on external carbon sources and achieve deep nitrogen removal. Furthermore, MABR biofilms possess high biomass and extracellular polymeric content, exhibiting a stable microbial community structure and greater resistance to salinity shocks and antibiotic stress compared to traditional processes. Therefore, employing MABR technology to construct simultaneous nitrification and denitrification processes can improve the stability and efficiency of marine aquaculture wastewater treatment, demonstrating promising application prospects. Summary of the Invention

[0006] The purpose of this invention is to provide...

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A low-carbon and high-efficiency marine aquaculture wastewater treatment device and method includes an influent unit, a treatment reaction unit, an effluent unit, an aeration unit, a mass transfer enhancement unit, a temperature control unit, and a dissolved oxygen monitoring unit. The water inlet unit transports the marine aquaculture wastewater to be treated to the treatment reaction unit; The treatment reaction unit includes a reaction vessel for containing wastewater to be treated, and a membrane aeration mechanism disposed inside the reaction vessel for attaching a biofilm and providing bubble-free oxygen supply. The membrane aeration mechanism is disposed inside the reaction vessel. The water outlet unit is used to discharge the treated water from the treatment reaction unit; The aeration unit includes a gas supply mechanism and a gas regulation mechanism, used to supply gas to the membrane aeration mechanism; The mass transfer enhancement unit is connected to the processing reaction unit and is used to enhance the mixing within the processing reaction unit; Both the temperature control unit and the dissolved oxygen monitoring unit are located within the processing reaction unit, and are used to maintain the medium temperature within the processing reaction unit and monitor the dissolved oxygen concentration within the processing reaction unit.

[0008] Preferably, the water inlet unit includes a water inlet tank and a water inlet pump; the reaction vessel is a sequencing batch reactor; the membrane aeration mechanism is a modified hollow fiber membrane module; and the water outlet unit includes a water outlet tank and a water outlet valve. The inlet tank is connected to the inlet end of the sequencing batch reactor via an inlet pump, and is used to pump the wastewater in the inlet tank into the sequencing batch reactor. The outlet of the sequencing batch reactor is connected to the outlet tank via an outlet valve, which is used by the sequencing batch reactor to discharge the treated water into the outlet tank. The modified hollow fiber membrane module is disposed within the sequencing batch reactor.

[0009] Preferably, the modified hollow fiber membrane module includes two sets of annular membrane modules and a plurality of PDMS hollow fiber membranes disposed between the two sets of annular membrane modules, wherein the outer surface of the PDMS hollow fiber membrane is coated with an outer rough hydrophilic material.

[0010] Preferably, the gas supply mechanism includes a gas pump, and the gas regulating mechanism includes a rotor flow meter for measuring gas flow, a pressure gauge for monitoring and regulating gas pressure, and a pressure valve. The modified hollow fiber membrane module in the sequencing batch reactor is supplied with gas through an external gas pump with a rotor flow meter. The pressure gauge and pressure valve are connected to an external pressure gauge with a pressure valve through a pipeline. This is used to monitor the pressure value of the gas in the membrane aeration mechanism in real time and to coordinate with the gas supply mechanism to adjust the gas supply flow rate in real time.

[0011] Preferably, the mass transfer enhancement unit includes a rotor disposed within the processing reaction unit and a magnetic stirrer for driving the rotor; the sequencing batch reactor is placed on the magnetic stirrer, and the rotor is disposed within the sequencing batch reactor and located at the bottom of the modified hollow fiber membrane assembly.

[0012] Preferably, the sequencing batch reactor is provided with a treatment cover over the modified hollow fiber membrane module, the treatment cover being used to protect the modified hollow fiber membrane module and improve temperature distribution; the temperature control unit is a water bath heating device 5, the water bath heating device 5 being disposed between the sequencing batch reactor and the treatment cover, for regulating the temperature inside the sequencing batch reactor.

[0013] Preferably, the dissolved oxygen monitoring unit is a DO detector, which is installed inside the treatment hood to monitor the dissolved oxygen concentration inside the treatment hood.

[0014] In addition, the present invention also provides a method for treating marine aquaculture wastewater using the aforementioned low-carbon and high-efficiency marine aquaculture wastewater treatment device, comprising the following steps: Step S1, Start-up of the synchronous nitrification-denitrification biofilm system: Inoculate activated sludge into the treatment reaction unit, and pump the antibiotic-containing marine aquaculture wastewater into the system through the influent unit; turn on the mass transfer enhancement unit and the aeration unit, and monitor and control the dissolved oxygen concentration in the treatment reaction unit to be less than 0.2 mg / L through the dissolved oxygen monitoring unit until the total nitrogen removal rate is stable at more than 80% and a stable biofilm is formed on the surface of the membrane aeration mechanism; Step S2, Gradient Acclimation and Operation: In the treatment reaction unit successfully started in Step S1, the influent salinity is gradually increased to 2.5%~4.0%, and the influent antibiotic concentration is gradually increased to 1 mg / L; the treatment reaction unit is controlled to operate in a sequential batch mode, with each cycle lasting 6 hours, sequentially performing feeding, stirring and aeration reaction, sedimentation, and drainage; the hydraulic retention time (HRT) is controlled to be 9~15 hours, and the water exchange rate is 50%; during operation, the dissolved oxygen concentration is controlled to be less than 0.2 mg / L by the dissolved oxygen monitoring unit, the pH is maintained at 7.5~8.0, and the temperature is controlled at 30±2 ℃ by the temperature control unit.

[0015] Preferably, in step S1, the concentration of the inoculated sludge is 3.0~6.0 g MLVSS / L; the concentration of ammonia nitrogen in the wastewater is 5~20 mg / L, the concentration of nitrate nitrogen is 10~30 mg / L, the concentration of COD is 80~150 mg / L, and the C / N ratio is 3.5~4.5.

[0016] Preferably, the gas flow rate of the aeration unit is 2~8 mL / min, and the lumen pressure of the membrane aeration mechanism is 2~5 kPa.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1) Based on the characteristics of MABR bubble-free aeration and heterogeneous mass transfer, this invention realizes a high-efficiency and low-carbon simultaneous nitrification and denitrification process, solving the technical problem of marine aquaculture wastewater treatment. 2) Under the conditions of adding a small amount of carbon source and low flow rate aeration, this invention achieves a high total nitrogen removal rate (80%) and a certain antibiotic biological removal capacity (60%~70%), meeting the relevant first-class discharge standards for aquaculture wastewater; it can also reduce sludge production, which is conducive to further reducing operating energy consumption and greenhouse gas emissions. 3) This invention achieves the adhesion of a large number of microorganisms by coating the surface of the hollow fiber membrane with a rough material with a lower Zeta potential and stronger hydrophilicity, thereby improving the stress resistance and impact resistance of the reaction system; the modification method is simple and easy to operate, and can achieve better removal effect under the same conditions, with green and environmentally friendly characteristics, and reduces the complexity of process operation.

[0018] In conclusion, the use of modified MABR to treat marine aquaculture wastewater is beneficial for achieving a low-carbon, efficient, and stable simultaneous nitrification and denitrification process, and has strong guiding significance for the biological treatment of marine aquaculture wastewater. Attached Figure Description

[0019] Figure 1 A schematic diagram of a low-carbon and high-efficiency marine aquaculture wastewater treatment device provided for an embodiment of the present invention; Figure 2 This is a schematic diagram of the modified hollow fiber membrane module in a low-carbon and high-efficiency marine aquaculture wastewater treatment device provided in an embodiment of the present invention.

[0020] The serial numbers in the diagram are as follows: 1. Inlet tank; 2. Sequencing batch reactor; 3. Outlet tank; 4. Inlet pump; 5. Water bath; 6. Magnetic stirrer; 7. Rotor; 8. Air pump; 9. Rotor flow meter; 10. Modified hollow fiber membrane module; 11. Pressure gauge; 12. Pressure valve; 13. Outlet valve; 14. DO detector; 15. Circular membrane module; 16. PDMS hollow fiber membrane; 17. Outer rough hydrophilic material; 18. Air inlet pipe; 19. Air outlet pipe; 20. Treatment hood. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0022] like Figure 1 As shown, this embodiment provides a low-carbon and efficient marine aquaculture wastewater treatment device and method, wherein the treatment device includes an influent unit, a treatment reaction unit, an effluent unit, an aeration unit, a mass transfer enhancement unit, a temperature control unit, and a dissolved oxygen monitoring unit.

[0023] The water intake unit includes a water intake tank 1 and a water intake pump 4, which are used to transport the marine aquaculture wastewater to be treated to the treatment reaction unit.

[0024] The treatment reaction unit is a sequencing batch reactor 2, used for the biochemical treatment of marine aquaculture wastewater. The inlet tank 1 is connected to the inlet end of the sequencing batch reactor 2 via an inlet pump 4, which pumps the synthetic wastewater from the inlet tank 1 into the sequencing batch reactor 2.

[0025] The sequencing batch reactor 2 is equipped with a modified hollow fiber membrane module 10, which serves as a membrane aeration mechanism for attaching biofilm and providing bubble-free oxygen supply.

[0026] like Figure 2 As shown, the modified hollow fiber membrane module 10 includes two sets of annular membrane modules 15 and a plurality of PDMS hollow fiber membranes 16 disposed between the two sets of annular membrane modules 15. The outer surface of the PDMS hollow fiber membranes 16 is coated with an outer rough hydrophilic material 17 to increase the amount of microorganisms that can adhere. Gas enters the annular membrane module 15 through the inlet pipe 18 and is evenly distributed to each membrane fiber. Residual gas is discharged through the outlet pipe 19.

[0027] The sequencing batch reactor 2 uses a water bath heating device 5 with a temperature control unit to maintain a constant temperature of 30°C, and uses a magnetic stirrer 6 as a mass transfer enhancement unit and a rotor 7 located inside the sequencing batch reactor 2 to enhance mass transfer.

[0028] The sequencing batch reactor 2 is placed on the magnetic stirrer 6, and the rotor 7 is located inside the sequencing batch reactor 2 and at the bottom of the modified hollow fiber membrane module 10.

[0029] Furthermore, in this embodiment, the sequencing batch reactor 2 is provided with a treatment hood 20 covering the modified hollow fiber membrane module 10. A water bath heating device 5 is disposed between the sequencing batch reactor 2 and the treatment hood 20 to regulate the temperature inside the sequencing batch reactor 2.

[0030] The effluent unit includes an effluent tank 3 and an effluent valve 13, which are used to discharge the treated water from the treatment reaction unit. The effluent end of the sequencing batch reactor 2 is connected to the effluent tank 3 through the effluent valve 13, which controls the discharge of the treated water from the sequencing batch reactor 2 into the effluent tank 3.

[0031] The aeration unit includes an air pump 8 for the gas supply mechanism and a gas regulating mechanism for supplying gas with controllable flow rate and pressure to the membrane aeration mechanism. The gas regulating mechanism includes a rotor flow meter 9 for measuring gas flow rate, a pressure gauge 11 for monitoring and regulating gas pressure, and a pressure valve 12. The air pump 8 is connected in sequence to the rotor flow meter 9, the modified hollow fiber membrane module 10, the pressure gauge 11, and the pressure valve 12.

[0032] The dissolved oxygen monitoring unit uses a DO detector 14 to monitor the dissolved oxygen concentration within the treatment reaction unit. The DO detector 14 is located inside the treatment hood 20.

[0033] In addition, this embodiment also provides a method for treating marine aquaculture wastewater based on the aforementioned device, including the following steps: Step S1, Start-up of the simultaneous nitrification-denitrification biofilm system: Inoculate activated sludge into the treatment reaction unit at a concentration of 3.0–6.0 g MLVSS / L; pump in antibiotic-containing marine aquaculture wastewater (ammonia nitrogen concentration of 5–20 mg / L, nitrate nitrogen concentration of 10–30 mg / L, organic matter COD concentration of 80–150 mg / L, C / N ratio of 3.5–4.5); turn on the mass transfer enhancement unit and aeration unit, monitor and control the dissolved oxygen concentration in the treatment reaction unit to be less than 0.2 mg / L through the dissolved oxygen monitoring unit, and complete the start-up when the total nitrogen removal rate is stable above 80% and a stable biofilm forms on the surface of the membrane aeration mechanism; Step S2, Reactor Operation Stage: In the treatment reaction unit successfully started in Step S1, the influent salinity is gradually increased to 2.5%~4.0%, and the influent antibiotic concentration is gradually increased to 1 mg / L; the treatment reaction unit is controlled to operate in a sequential batch mode, with each cycle lasting 6 hours, sequentially performing feeding, stirring and aeration reaction, sedimentation, and drainage; the hydraulic retention time (HRT) is controlled to be 9~15 hours, and the water exchange rate is 50%; during operation, the dissolved oxygen concentration is controlled to be less than 0.2 mg / L through the dissolved oxygen monitoring unit, the pH is maintained at 7.5~8.0, and the temperature is controlled at 30±2 ℃ through the temperature control unit.

[0034] The gas flow rate of the aeration unit is 2~8 mL / min.

[0035] The operational results of this embodiment show that the sequencing batch reactor (SBR) equipped with modified hollow fiber membrane modules can still achieve a total nitrogen removal rate of approximately 85% and an antibiotic degradation rate of approximately 60% under the dual stress of 3.5% salinity and 0.8 mg / L antibiotics. The effluent quality meets the first-level discharge limit (≤3.5 mg N / L) of total nitrogen in the Hainan Province Aquaculture Wastewater Discharge Standard (DB46 / 475-2023). In contrast, the unmodified reactor showed inhibited biological activity and accumulation of nitrite and nitrate in the effluent after the salinity increased to 2.5%. However, due to the advantages of simultaneous nitrification and denitrification in MABR, it can still meet the second-level discharge limit requirements of the Hainan Province Aquaculture Wastewater Discharge Standard.

[0036] Therefore, MABR can enhance the stability of the simultaneous nitrification and denitrification process for marine aquaculture wastewater, and the modified hollow fiber membrane module further improves the treatment efficiency of the method.

[0037] The following details the specific parameters: Example In this embodiment, artificially synthesized seawater aquaculture wastewater is used, and the specific water quality is as follows: The ammonia nitrogen concentration was 10 mg / L, the nitrate nitrogen concentration was 15 mg / L, and the organic matter COD concentration was 100 mg / L; the pH was controlled at 7.7±0.2. The influent salinity was gradually increased (0, 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%) and the antibiotic concentration (sulfamethoxazole, 0, 0.05 mg / L, 0.1 mg / L, 0.2 mg / L, 0.4 mg / L, 0.6 mg / L, 0.8 mg / L).

[0038] Two sequencing batch reactors (SBRs) were installed. One SBR used a modified hollow fiber membrane module, while the other used a conventional PDMS hollow fiber membrane module. The second SBR had an effective volume of 3.2 L, was inoculated with municipal sludge, and operated in a flow-conditioning-sedimentation-drainage mode.

[0039] The specific steps of the processing are as follows: Step S1: Start-up of the simultaneous nitrification-denitrification biofilm system: Inoculate municipal sludge into the 3.2L effective volume sequencing batch reactor 2. Pump synthetic marine aquaculture wastewater (ammonia nitrogen concentration 10 mg / L, nitrate nitrogen concentration 15 mg / L, organic matter COD concentration 100 mg / L; pH controlled at 7.7±0.2) into the sequencing batch reactor 2 via influent pump 4. Turn on the magnetic stirrer 6 and air pump 8. Adjust the pressure in the cavity of the modified hollow fiber membrane module 10 to 2~5 kPa using pressure gauge 11 and pressure valve 12, and monitor and adjust the dissolved oxygen concentration in the sequencing batch reactor 2 to be less than 0.2 mg / L using rotor flow meter 9 and DO detector 14. During operation, use water bath heating 5 to maintain a constant temperature of 30±2℃ inside the sequencing batch reactor 2. Start-up is complete when the total nitrogen removal rate is stable above 80% and a stable biofilm forms on the surface of the modified hollow fiber membrane module 10.

[0040] Step S2, Reactor Gradient Acclimation and Operation: In the successfully started-up sequencing batch reactor 2 (SBR) from step S1, the influent salinity was gradually increased (0, 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%) to simulate real marine aquaculture wastewater, and the influent antibiotic concentration (sulfamethoxazole, 0, 0.05 mg / L, 0.1 mg / L, 0.2 mg / L, 0.4 mg / L, 0.6 mg / L, 0.8 mg / L) was gradually increased. SBR 2 was operated in batch mode for 6 hours per cycle, with the following operating parameters: feed 15 min, agitation and aeration 310 min; settling 22 min; effluent discharge 8 min; effluent ratio 50%. During operation, dissolved oxygen concentration was controlled to be less than 0.2 mg / L using DO detector 14, pH was maintained between 7.5 and 8.0, and temperature was controlled at 30 ± 2 °C using water bath heating 5.

[0041] The specific steps of each cycle in the sequential batch processing mode are as follows: 1) The synthetic wastewater is pumped into the sequencing batch reactor via inlet pump 4; 2) Turn on the magnetic stirrer 6 and the air pump 8, and adjust the pressure in the tube to 2~5 kPa through the pressure gauge 11 and the pressure valve 12. Monitor and adjust the pressure through the rotor flow meter 9 and the DO detector 14 to make the DO concentration in the sequencing batch reactor 2 less than 0.2 mg / L. 3) During operation, a water bath heating 5 is used to maintain a constant temperature of 30±2℃ inside the sequencing batch reactor 2; 4) After aeration for 310 minutes, turn off the magnetic stirrer 6 and the air pump 8; 5) After settling for 22 minutes, open the effluent valve 13 to discharge the effluent from the sequencing batch reactor 2 into the effluent tank 3, with a discharge ratio of 50%. 6) After drainage is completed, turn on the inlet pump 4 to pump seawater aquaculture wastewater into the sequencing batch reactor 2 and repeat the above steps.

[0042] This embodiment sets up two sequencing batch reactors for comparison, one using a modified hollow fiber membrane module and the other using a conventional PDMS hollow fiber membrane module.

[0043] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A low-carbon, high-efficiency marine aquaculture wastewater treatment device and method, characterized in that, It includes an inlet unit, a treatment reaction unit, an outlet unit, an aeration unit, a mass transfer enhancement unit, a temperature control unit, and a dissolved oxygen monitoring unit; The water inlet unit transports the marine aquaculture wastewater to be treated to the treatment reaction unit; The treatment reaction unit includes a reaction vessel for containing wastewater to be treated, and a membrane aeration mechanism disposed inside the reaction vessel for attaching a biofilm and providing bubble-free oxygen supply. The membrane aeration mechanism is disposed inside the reaction vessel. The water outlet unit is used to discharge the treated water from the treatment reaction unit; The aeration unit includes a gas supply mechanism and a gas regulation mechanism, used to supply gas to the membrane aeration mechanism; The mass transfer enhancement unit is connected to the processing reaction unit and is used to enhance the mixing within the processing reaction unit; Both the temperature control unit and the dissolved oxygen monitoring unit are located within the processing reaction unit, and are used to maintain the medium temperature within the processing reaction unit and monitor the dissolved oxygen concentration within the processing reaction unit.

2. The low-carbon and high-efficiency marine aquaculture wastewater treatment device and method according to claim 1, characterized in that, The water inlet unit includes a water inlet tank (1) and a water inlet pump (4); the reaction vessel is a sequencing batch reactor (2); the membrane aeration mechanism is a modified hollow fiber membrane module (10); the water outlet unit includes a water outlet tank (3) and a water outlet valve (13); The inlet tank (1) is connected to the inlet end of the sequencing batch reactor (2) via an inlet pump (4) for pumping wastewater from the inlet tank (1) into the sequencing batch reactor (2). The outlet of the sequencing batch reactor (2) is connected to the outlet tank (3) via an outlet valve (13), which is used by the sequencing batch reactor (2) to discharge the treated water into the outlet tank (3). The modified hollow fiber membrane module (10) is disposed in the sequencing batch reactor (2).

3. The low-carbon and high-efficiency marine aquaculture wastewater treatment device and method according to claim 2, characterized in that, The modified hollow fiber membrane module (10) includes two sets of annular membrane modules (15) and a plurality of PDMS hollow fiber membranes (16) disposed between the two sets of annular membrane modules (15). The outer surface of the PDMS hollow fiber membrane (16) is covered with an outer rough hydrophilic material (17).

4. The low-carbon and high-efficiency marine aquaculture wastewater treatment device and method according to claim 2, characterized in that, The gas supply mechanism includes a gas pump (8), and the gas regulating mechanism includes a rotor flow meter (9) for measuring gas flow, a pressure gauge (11) for monitoring and regulating gas pressure, and a pressure valve (12). The modified hollow fiber membrane module (10) in the sequencing batch reactor (2) is supplied with gas through an air pump (8) with a rotor flow meter (9) connected to an external pipeline; The pressure gauge (11) and pressure valve (12) are connected to the external pressure gauge (11) with pressure valve (12) through the pipeline. They are used to monitor the pressure value of the gas in the membrane aeration mechanism in real time and coordinate with the gas supply mechanism to adjust the gas supply flow rate in real time.

5. The low-carbon and high-efficiency marine aquaculture wastewater treatment device according to claim 2, characterized in that, The mass transfer enhancement unit includes a rotor (7) disposed in the processing reaction unit and a magnetic stirrer (6) for driving the rotor (7); the sequencing batch reactor (2) is placed on the magnetic stirrer (6), the rotor (7) is disposed in the sequencing batch reactor (2) and located at the bottom of the modified hollow fiber membrane assembly (10).

6. The low-carbon and high-efficiency marine aquaculture wastewater treatment device according to claim 2, characterized in that, The sequencing batch reactor (2) is equipped with a treatment hood (20) covering the modified hollow fiber membrane module (10). The treatment hood (20) is used to protect the modified hollow fiber membrane module (10) and improve the temperature distribution. The temperature control unit adopts a water bath heating device (5). The water bath heating device (5) is set between the sequencing batch reactor (2) and the treatment hood (20) to regulate the temperature inside the sequencing batch reactor (2).

7. The low-carbon and high-efficiency marine aquaculture wastewater treatment device according to claim 6, characterized in that, The dissolved oxygen monitoring unit uses a DO detector (14), which is installed inside the treatment hood (20) to monitor the dissolved oxygen concentration inside the treatment hood (20).

8. A method for treating marine aquaculture wastewater based on the low-carbon, high-efficiency marine aquaculture wastewater treatment device according to any one of claims 1-7, characterized in that, Includes the following steps: Step S1, Start-up of the synchronous nitrification-denitrification biofilm system: Inoculate activated sludge into the treatment reaction unit, and pump the antibiotic-containing marine aquaculture wastewater into the system through the influent unit; turn on the mass transfer enhancement unit and the aeration unit, and monitor and control the dissolved oxygen concentration in the treatment reaction unit to be less than 0.2 mg / L through the dissolved oxygen monitoring unit until the total nitrogen removal rate is stable at more than 80% and a stable biofilm is formed on the surface of the membrane aeration mechanism; Step S2, Reactor Operation Stage: In the treatment reaction unit successfully started in Step S1, the influent salinity is gradually increased to 2.5%~4.0%, and the influent antibiotic concentration is gradually increased to 1 mg / L; the treatment reaction unit is controlled to operate in a sequential batch mode, with each cycle lasting 6 hours, sequentially performing feeding, stirring and aeration reaction, sedimentation, and drainage; the hydraulic retention time (HRT) is controlled to be 9~15 hours, and the water exchange rate is 50%; during operation, the dissolved oxygen concentration is controlled to be less than 0.2 mg / L by the dissolved oxygen monitoring unit, the pH is maintained at 7.5~8.0, and the temperature is controlled at 30±2 ℃ by the temperature control unit.

9. The method according to claim 8, characterized in that, In step S1, the concentration of the inoculated activated sludge is 3.0~6.0 g MLVSS / L; the concentration of ammonia nitrogen in the wastewater is 5~20 mg / L, the concentration of nitrate nitrogen is 10~30 mg / L, the concentration of COD is 80~150 mg / L, and the C / N ratio is 3.5~4.

5.

10. The method according to claim 8, characterized in that, The gas flow rate of the aeration unit is 2~8 mL / min, and the lumen pressure of the membrane aeration mechanism is 2~5 kPa.

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