A microalgae filter bed coupled microbial fuel cell system and a method for treating sewage and controlling ARGs transmission thereof

Abstract

The application relates to the technical field of water treatment, and specifically discloses a microalgae filter bed coupled microbial fuel cell system and a method for treating sewage and controlling ARGs propagation. The microalgae filter bed coupled microbial fuel cell system comprises a body, an anaerobic zone arranged in the body, and the anaerobic zone comprises, in sequence, an anode electrode arranged on one side of a first activated carbon layer and inoculated with an anode microalgae; and an aerobic zone arranged in the body and arranged in sequence with the aerobic zone along the height direction of the body, the aerobic zone comprising, in sequence, a cathode electrode arranged on one side of a second activated carbon layer and inoculated with a cathode microalgae, and the cathode electrode is electrically connected with the anode electrode; and the anode microalgae and the cathode microalgae are both selected from eukaryotic microalgae. The system can be used in water treatment, and has the advantages of simple structure, flexible operation, rapid start, no need for aeration, stable operation, low cost and the like.

Description

Technical Field

[0001] This application relates to the technical field of water treatment, and more specifically, it relates to a microalgae filter bed coupled with a microbial fuel cell system and a method for treating wastewater and controlling the propagation of ARGs. Background Technology

[0002] Antibiotics are widely used in the medical and aquaculture industries. Even at low residual concentrations, antibiotics can still affect biological functions, leading to chronic poisoning effects in aquatic organisms. Simultaneously, antibiotic residues can induce the development of antibiotic-resistant bacteria (ARBs) and antibiotic resistance genes (ARGs). ARGs are characterized by horizontal transfer and poor biodegradability, allowing them to spread in media such as soil and water, and even through the food chain, posing a significant threat to the ecological environment and human health.

[0003] Traditional ecological filter beds are a low-cost, eco-friendly wastewater treatment process widely used in aquaculture and livestock farming. Microbial fuel cells (MFCs) are a novel energy and wastewater purification technology that uses microorganisms as catalysts to oxidize organic and inorganic substances while simultaneously generating electricity. By filling the filter bed with conductive carbonaceous materials, an ecological filter bed can be transformed into a short-circuit microbial fuel cell, achieving efficient pollutant treatment while generating electricity. It offers certain advantages over conventional wetlands in removing antibiotics and controlling ARGs (antibiotic-dependent oxidative stresses). However, research shows that ARGs still exist in the effluent of the coupled system. Furthermore, the oxygen at the cathode is sourced from natural dissolved oxygen or artificial oxygenation, and the redox gradient between the anode and cathode is limited. Therefore, improvements to the coupled system are urgently needed. Summary of the Invention

[0004] To improve the removal efficiency of ARGs by the coupling system, this application provides a microalgae filter bed coupled with a microbial fuel cell system and its application.

[0005] This application provides a microalgae filter bed coupled with a microbial fuel cell system, which adopts the following technical solution:

[0006] In a first aspect, this application provides a microalgae filter bed coupled with a microbial fuel cell system, comprising:

[0007] ontology;

[0008] An anaerobic zone, wherein the anaerobic zone is located within the main body, and the anaerobic zone comprises, in sequence:

[0009] A first activated carbon layer, which is used for filtration;

[0010] An anode electrode is disposed on one side of the first activated carbon layer and is inoculated with anode microalgae;

[0011] An aerobic zone is located on the main body, and the aerobic zones are arranged sequentially along the height direction of the main body. The aerobic zones include the following sequentially arranged aerobic zones:

[0012] A second activated carbon layer is used for filtration.

[0013] A cathode electrode is disposed on one side of the second activated carbon layer, and the cathode electrode is inoculated with cathode microalgae. The cathode electrode is electrically connected to the anode electrode.

[0014] Both the anode microalgae and the cathode microalgae are eukaryotic microalgae.

[0015] By adopting the above technical solution, this application utilizes the redox gradient to match the microbial fuel cell, and introduces microalgae into the aerobic and anaerobic zones to form a symbiotic system of bacteria and algae, making full use of multiple mechanisms of action such as ecology, biology, electrochemistry and bioelectrochemistry to enhance antibiotic removal and ARGs control.

[0016] In this application, microalgae are preferably inoculated on both the anode and cathode electrodes. Microalgae possess multiple removal mechanisms for antibiotics, including adsorption, accumulation, biodegradation, photodegradation, and hydrolysis. Furthermore, due to the phylogenetic distance between eukaryotes and prokaryotes, eukaryotic microalgae act as a natural barrier, effectively controlling the transfer of ARGs between symbiotic bacteria, thereby reducing the abundance of ARGs in the substrate during wastewater treatment. Simultaneously, in the MFC anode, microalgae can transfer electrons to the anode via electron mediators and provide substrate for the anode; in the MFC cathode, they can produce oxygen and act as cathode electron acceptors.

[0017] Optionally, the anodic microalgae is Chlorella vulgaris, and the acclimatization conditions for the anodic microalgae are cultivation under dark and low light conditions.

[0018] By adopting the above technical solution, anodic microalgae grow anaerobically and autotrophically in a dark environment, and together with bacteria, they provide electron donors to form a symbiotic system. During coexistence, bacteria and microalgae exchange various nutrients and secrete signaling substances to achieve better synergy, promote the generation of bioelectricity, and effectively enhance the wastewater treatment efficiency of the system.

[0019] Optionally, the cathode microalgae may be Chlorella vulgaris or Tetracyclina obliqueis, and the acclimatization conditions for the cathode microalgae are 12 hours of light exposure and 12 hours of darkness exposure.

[0020] By adopting the above technical solution, cathode microalgae can use photosynthesis to absorb CO2, nitrogen, and phosphorus from wastewater as nutrients, deeply purify wastewater while producing oxygen, improve power generation efficiency while reducing greenhouse gas emissions.

[0021] Optionally, the first activated carbon layer and the second activated carbon layer are respectively filled with activated carbon, and the particle size of the activated carbon is 1-2 mm.

[0022] By adopting the above technical solution, the particle size of activated carbon was optimized. The appropriate particle size can fully adsorb adsorbable impurities in wastewater, thereby improving the system's wastewater purification effect.

[0023] Optionally, the anode electrode and the cathode electrode each include two interlayers and a hydrophilic graphite carbon felt, wherein the hydrophilic graphite carbon felt is disposed between the two interlayers.

[0024] By adopting the above technical solution, graphite carbon felt can serve as the main carrier for microorganisms, enriching them and enabling them to undergo oxidation-reduction at the anode and cathode electrodes, generating electrons. The two interlayers enhance the electron collection capacity of the second anode or cathode. The combination of graphite carbon felt and the two interlayers stabilizes and enhances the electron collection and transfer efficiency of the anode and cathode electrodes.

[0025] Optionally, the body further includes a support layer and a transition layer, wherein the support layer, the aerobic zone, the transition layer, and the anaerobic zone are arranged sequentially from bottom to top along the height direction of the body.

[0026] By adopting the above technical solution and setting up the support layer, not only can some impurities be initially filtered, but the water distribution can also be made more uniform. The transition layer can clearly divide the microbial functional zones of the system.

[0027] Optionally, the main body is provided with an inlet pipe and an outlet pipe, the inlet pipe being located at one end of the main body near the supporting layer, and the outlet pipe being located at one end of the main body near the aerobic zone.

[0028] By adopting the above technical solution, the inlet and outlet pipes are designed so that the water flow direction in the system is vertical from bottom to top, which can prolong the retention time of sewage in the system and improve the system's sewage treatment effect.

[0029] Optionally, the supporting layer is filled with gravel with a particle size of 6-8 mm; the transition layer is filled with iron ore with a particle size of 2-6 mm.

[0030] By adopting the above technical solution, it is preferable to use gravel to fill the supporting layer, and the particle size of the gravel is optimized to ensure that the gravel can exist stably in the system, is not easily lost, and gives the supporting layer excellent uniform water distribution. It is also preferable to fill the transition layer with iron ore, and the particle size of the iron ore is optimized.

[0031] Secondly, this application provides a method for preparing a microalgae filter bed coupled with a microbial fuel cell system, which adopts the following technical solution:

[0032] A method for treating antibiotic-containing wastewater and controlling the spread of antibiotic resistance genes using a microalgae filter bed coupled with a microbial fuel cell system includes the following steps:

[0033] S1. Before use: Inoculate anaerobic sludge and anodic microalgae onto the anode electrode in the anaerobic zone, and inoculate cathode microalgae in the logarithmic growth phase onto the cathode electrode in the aerobic zone.

[0034] S2. Water treatment: Antibiotic-containing wastewater is pumped in from the bottom of the main body, then treated sequentially by the anaerobic zone and the aerobic zone, and finally discharged from the top of the main body.

[0035] By adopting the above technical solution, a device using a microalgae filter bed coupled with a microbial fuel cell system is used for wastewater treatment under a vertical upflow inlet method, which maintains the ecological characteristics, is simple to operate, and has low operating costs.

[0036] Optionally, in step S2, the hydraulic residence time is 48 hours.

[0037] By adopting the above technical solution, the hydraulic retention time is optimized, enabling the system to fully adsorb, accumulate, biodegrade, photodegrade, and hydrolyze antibiotics in wastewater, thereby effectively removing ARGs from the wastewater.

[0038] In summary, this application has the following beneficial effects:

[0039] 1. In this application, the redox gradient of the vertical flow filter bed is matched with that of the microbial fuel cell, and microalgae are introduced to form a symbiotic system in the anode and cathode regions. This fully utilizes multiple mechanisms of action, including ecological, biological, electrochemical and bioelectrochemical processes, to enhance antibiotic removal and ARGs control.

[0040] 2. In this application, it is preferred to inoculate anodic microalgae on the anode electrode. The anodic microalgae grow anaerobically and autotrophically in the dark environment and together with bacteria provide electron donors to form a bacterial-algae symbiotic system. During coexistence, bacteria and microalgae exchange various nutrients and secrete signaling substances to achieve better synergistic effects, promote the generation of bioelectricity, and effectively enhance the wastewater treatment efficiency of the system.

[0041] 3. In this application, it is preferred to inoculate cathode microalgae on the cathode electrode. The cathode microalgae can use photosynthesis to absorb CO2, nitrogen and phosphorus in wastewater as nutrients, deeply purify wastewater and produce oxygen at the same time, improve power generation efficiency and reduce greenhouse gas emissions.

[0042] 4. This application screens microalgae suitable for different regional environments of the system, forming a symbiotic system of bacteria and algae in the anode and eccentric zones. Through the synergistic effect between bacteria and algae, the aim is to enhance wastewater treatment efficiency and effectively reduce the risk of antibiotic resistance gene transmission. It has advantages such as simple structure, flexible operation, rapid start-up, no need for aeration, stable operation, and low cost.

[0043] 5. The method of this application uses a device with a microalgae filter bed coupled with a microbial fuel cell system to treat sewage in a vertical upflow water intake mode, which maintains the ecological characteristics, is simple to operate, and has low operating costs. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the system architecture of this application.

[0045] Explanation of reference numerals in the attached diagram: 1. Inlet pipe; 2. Support layer; 3. First activated carbon layer; 4. Anode electrode; 5. Anode microalgae; 6. Transition layer; 7. Second activated carbon layer; 8. Cathode electrode; 9. Cathode microalgae; 10. Wire; 11. Resistor; 12. Outlet pipe. Detailed Implementation

[0046] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. After reading this invention, any modifications of the invention in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

[0047] The accompanying drawings are for illustrative purposes only. To better illustrate this embodiment, some components in the drawings may be omitted, enlarged, or reduced. They do not represent the actual dimensions of the product. Terms such as "upper," "lower," "top," "bottom," "side," "outer," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the purpose of facilitating the description of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0048] Example

[0049] Example 1

[0050] On one hand, this application provides a microalgae filter bed coupled microbial fuel cell system, including a body. The body is provided with a support layer 2, an anaerobic zone, a transition layer 6 and an aerobic zone in sequence from bottom to top along the height direction of the body. The body is connected to an inlet pipe 1 and an outlet pipe 12. The inlet pipe 1 is connected to the end of the body near the support layer 2, and the outlet pipe 12 is connected to the end of the body near the aerobic zone.

[0051] Specifically, the main body is a cylinder with a height of 45cm and a diameter of 10cm, with a total volume of 3.14L. The main body is filled with wetland filler material, which is configured with a support layer 2, an anaerobic zone, a transition layer 6, and an aerobic zone. The effective volume after the wetland filler material is filled is 1.08L. The support layer 2 is 25cm high, the anaerobic zone is 5cm high, the transition layer 6 is 10cm high, and the aerobic zone is 5cm high.

[0052] Wastewater containing antibiotics enters the main body through the inlet and passes vertically from bottom to top through the support layer 2, anaerobic zone, transition layer 6, and aerobic zone. Finally, it overflows through the outlet pipe 12. The aerobic and anaerobic zones work together to form an oxidation-reduction system and a microbial fuel cell, which can remove antibiotics in wastewater through adsorption, accumulation, biodegradation, photodegradation, and hydrolysis, effectively reducing the amount of antibiotics in the wastewater and inhibiting the spread of ARGs.

[0053] refer to Figure 1 The support layer 2 is filled with gravel with a particle size of 6-8mm. The particle size of the gravel can be 6mm, 7mm, or 8mm. Gravel within this particle size range can be used to fill the support layer 2. Gravel is readily available and inexpensive, and gravel of this size is not easily lost from the body, thus playing a role in uniform water distribution.

[0054] refer to Figure 1 The anaerobic zone is located above the support layer 2 and consists of a first activated carbon layer 3 and an anode electrode 4. The anode electrode 4 is installed at the end of the first activated carbon layer 3 furthest from the support layer 2. The first activated carbon layer 3 is filled with activated carbon particles with a particle size of 1-2 mm. The particle size of the activated carbon can be either 1 mm or 2 mm; activated carbon particles within this size range can be used to fill the activated carbon layer. This process can pre-adsorb and remove impurities from the wastewater, thus fully purifying it. The anode electrode 4 is inoculated with anode microalgae 5, which is a eukaryotic microalgae. Specifically, the anode microalgae 5 is Chlorella sp., which needs to be cultivated and acclimatized in darkness and low light.

[0055] Anodic microalgae 5 can remove antibiotics. Furthermore, anodic microalgae 5 grows anaerobically and autotrophically in a dark environment, providing electron donors together with bacteria to form a symbiotic system. During coexistence, bacteria and microalgae exchange various nutrients and secrete signaling substances to achieve better synergistic effects, promote the generation of bioelectricity, and effectively enhance the wastewater treatment efficiency of the system.

[0056] refer to Figure 1 The transition layer 6 is located between the anaerobic and aerobic zones. It is filled with iron ore particles with a diameter of 2-6 mm. The particle size of the iron ore can be 2 mm, 4 mm, or 6 mm; any iron ore particle within this range can be used to fill the transition layer 6. The transition layer 6 clearly distinguishes the anaerobic and aerobic zones, allowing the microalgae in each zone to function independently and complete the construction of the microbial battery within the organism.

[0057] refer to Figure 1 The aerobic zone is located above the transition layer 6 and consists of a second activated carbon layer 7 and a cathode electrode 8. The cathode electrode 8 is installed on the side of the second activated carbon layer 7 away from the transition layer 6. The second activated carbon layer 7 is filled with activated carbon particles with a particle size of 1-2 mm. The particle size of the activated carbon can be 1 mm or 2 mm; activated carbon particles within this particle size range can be used to fill the activated carbon layer. Cathode microalgae 9 are inoculated on the cathode electrode 8. The cathode microalgae 9 are eukaryotic microalgae. Optionally, the cathode microalgae 9 can be Chlorella sp. or Tetradesmus obliquus; specifically, in this embodiment, Tetradesmus obliquus is selected as the cathode microalgae 9. The Chlorella sp. used for the cathode microalgae 9 needs to be acclimated under 12 hours of light and 12 hours of darkness. The cathode electrode 8 is electrically connected to the anode electrode 4 to realize the construction of the microbial battery. Specifically, the cathode electrode 8 and the anode electrode 4 are connected by a copper wire 10 or a titanium wire 10. In this embodiment, the cathode electrode 8 and the anode electrode 4 are connected by a titanium wire 10, and the connection point is insulated and sealed. A 1000Ω resistor 11 is used to connect the two titanium wires 10 to form a closed loop, thus stably constructing a microalgae filter bed coupled with a microbial fuel cell system.

[0058] The cathode microalgae 9 can utilize photosynthesis to absorb CO2, nitrogen, and phosphorus from wastewater as nutrients, deeply purifying wastewater while generating oxygen, improving power generation efficiency while reducing greenhouse gas emissions.

[0059] refer to Figure 1 The cathode electrode 8 and the anode electrode 4 each include two clamping layers and a layer of hydrophilic graphite carbon felt. The two clamping layers clamp the hydrophilic graphite carbon felt. The clamping layers are stainless steel mesh, which can enhance the efficiency of electron collection and transfer and improve the power generation effect of the microbial fuel cell.

[0060] On the other hand, this application provides a method for treating wastewater and controlling the spread of ARGs using a microalgae filter bed coupled with a microbial fuel cell system, comprising the following steps:

[0061] S1. Before use: Inoculate a certain amount of anaerobic sludge and anodic microalgae 5 on the anode electrode 4 in the anaerobic zone. The dry weight ratio of sludge to microalgae is about 5:1. Inoculate cathode microalgae 9 in the logarithmic growth phase on the surface of the cathode electrode 8 in the aerobic zone.

[0062] S2. Water treatment: Antibiotic-containing wastewater is pumped into the bottom of the microalgae filter bed coupled with microbial fuel cell system, and then treated sequentially by the support layer 2, anode area, transition layer 6 and cathode area. Finally, it overflows from the top of the microalgae filter bed coupled with microbial fuel cell system and is discharged. The hydraulic retention time is 48 hours.

[0063] In this process, the anaerobic zone's anode microalgae 5 transfer electrons to the anode via an electron mediator and provide substrate for the anode. The synergistic effect of bacteria and algae promotes the generation of bioelectricity, effectively enhancing the system's wastewater treatment efficiency. In the aerobic zone, the microalgae produce oxygen, which acts as an electron acceptor at the cathode, combining with diffused protons to generate water, thus completing the cathode electrochemical reaction. The system fully utilizes the various removal effects of microalgae on antibiotics, including adsorption, accumulation, biodegradation, photodegradation, and hydrolysis. Furthermore, due to the phylogenetic distance between eukaryotes and prokaryotes, the transfer of ARGs between symbiotic bacteria can be effectively controlled, thereby reducing the abundance of ARGs in the sludge during wastewater treatment.

[0064] During operation, wastewater flowed into the system via a peristaltic pump and inlet pipe 1. The actual average influent COD concentration was 555.11 ± 12.82 mg / L, and the actual average influent ammonia nitrogen concentration was 55.14 ± 1.23 mg / L. The hydraulic retention time was 2 days. The system operated continuously for 2 months, and the effluent quality was monitored every 3 days. Specific measurement results are shown in the table below.

[0065] Table 1. Removal rates of COD, ammonia nitrogen, and antibiotics in the effluent from the example.

[0066] Test metrics COD ammonia nitrogen SMX TC Removal rate (%) 93.83 69.65 96.49 98.96

[0067] Table 2 Abundance of ARGs in the matrix of the examples

[0068] Types of resistance genes intⅠ1 sulⅠ sulⅡ tetA tetC Absolute abundance of anode (copies / g) 7.2349 7.9483 6.9430 6.7663 3.9805 Absolute abundance of cathode (copies / g) 7.8276 8.6287 8.4531 7.5933 3.7117

[0069] Combining the test results in Tables 1 and 2, it can be seen that after wastewater treatment, COD, ammonia nitrogen, and antibiotics in the effluent all have high removal rates, while the abundance of ARGs in the matrix remains at a low level.

[0070] Example 2

[0071] The difference from Example 1 is that some Haematococcus pluvialis is inoculated on the cathode electrode.

[0072] During operation, wastewater flowed into the system via a peristaltic pump and inlet pipe 1. The actual average influent COD concentration was 555.11 ± 12.82 mg / L, and the actual average influent ammonia nitrogen concentration was 55.14 ± 1.23 mg / L. The hydraulic retention time was 2 days. The system operated continuously for 2 months, and the effluent quality was monitored every 3 days. Specific measurement results are shown in the table below.

[0073] Table 3. Removal rates of COD, ammonia nitrogen, and antibiotics in the effluent from the example.

[0074] Test metrics COD ammonia nitrogen SMX TC Removal rate (%) 94.25 70.11 96.89 98.97

[0075] Table 4. Abundance of ARGs in the matrix of the examples.

[0076] Types of resistance genes intⅠ1 sulⅠ sulⅡ tetA tetC Absolute abundance of anode (copies / g) 6.8462 7.3264 6.4627 6.2538 3.2403 Absolute abundance of cathode (copies / g) 7.2371 8.1025 7.9837 7.0345 3.0451

[0077] As shown in Tables 1, 2, 3, and 4, under the same influent water quality, the effluent COD removal rate was 94.25%, the effluent ammonia nitrogen removal rate was 70.11%, the SMX removal rate was 96.89%, and the TC removal rate was 98.97%. The abundance of ARGs in the matrix is ​​shown in Table 4. In this embodiment, due to the inoculation of Haematococcus pluvialis, free radicals can be inhibited, thereby inhibiting ARGs. Therefore, the microalgae filter bed coupled with the microbial fuel cell system can maintain better water purification performance while achieving a lower level of ARG accumulation in the matrix.

[0078] Comparative Example

[0079] Comparative Example 1

[0080] The difference between this comparative example and Example 1 is that no microalgae were inoculated on the cathode electrode in this comparative example.

[0081] During operation, wastewater flowed into the system via a peristaltic pump and inlet pipe 1. The actual average influent COD concentration was 555.11 ± 12.82 mg / L, and the actual average influent ammonia nitrogen concentration was 55.14 ± 1.23 mg / L. The hydraulic retention time was 2 days. The system operated continuously for 2 months, and the effluent quality was monitored every 3 days. Specific measurement results are shown in the table below.

[0082] Table 5. Removal rates of COD, ammonia nitrogen, and antibiotics in the comparative effluent.

[0083]

[0084]

[0085] Table 6. Abundance of ARGs in comparative matrices

[0086] Types of resistance genes intⅠ1 sulⅠ sulⅡ tetA tetC Absolute abundance of anode (copies / g) 8.4728 9.0440 7.8804 7.9876 5.2396 Absolute abundance of cathode (copies / g) 8.9961 9.3609 7.7541 8.8262 4.1579

[0087] As shown in Tables 1, 2, 5, and 6, under the same influent water quality, the system without microalgae inoculation achieved an effluent COD removal rate of 89.11%, an effluent ammonia nitrogen removal rate of 47.12%, an SMX removal rate of 86.52%, and a TC removal rate of 98.65%. The abundance of ARGs in the substrate is shown in Table 3. In comparison, the microalgae filter bed coupled with a microbial fuel cell system maintains better water purification performance while achieving a lower level of ARG accumulation in the substrate.

[0088] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A method for treating antibiotic wastewater and controlling the spread of antibiotic-resistant genes (ARGs) using a microalgae filter bed coupled with a microbial fuel cell system. The microalgae filter bed coupled with the microbial fuel cell system includes: ontology; An anaerobic zone, wherein the anaerobic zone is located within the main body, and the anaerobic zone comprises, in sequence: The first activated carbon layer (3) is used for filtration; Anode electrode (4), the anode electrode (4) is disposed on one side of the first activated carbon layer (3), and the anode electrode (4) is inoculated with anode microalgae (5); The aerobic zone, located within the main body, comprises the following sequentially arranged aerobic zones: The second activated carbon layer (7) is used for filtration; A cathode electrode (8) is disposed on one side of the second activated carbon layer (7), and the cathode electrode (8) is inoculated with cathode microalgae (9). The cathode electrode (8) is electrically connected to the anode electrode (4). Both the anode microalgae (5) and the cathode microalgae (9) are eukaryotic microalgae. The anodic microalgae (5) is Chlorella vulgaris, and the acclimatization conditions of the anodic microalgae (5) are cultured in darkness and low light. The cathode microalgae (9) is selected from Chlorella vulgaris or Tetracyclella obliqueis. The acclimatization conditions of the cathode microalgae (9) are 12h light exposure and 12h light avoidance. The main body also includes a support layer (2) and a transition layer (6), wherein the support layer (2), the anaerobic zone, the transition layer (6) and the aerobic zone are arranged sequentially from bottom to top along the height direction of the main body; The supporting layer (2) is filled with gravel with a particle size of 6-8 mm; the transition layer (6) is filled with iron ore with a particle size of 2-6 mm; characterized in that it includes the following steps: S1. Before use: Inoculate anaerobic sludge and anodic microalgae (5) onto the anode electrode (4) in the anaerobic zone, and inoculate cathode microalgae (9) in the logarithmic growth phase onto the cathode electrode (8) in the aerobic zone. S2. Water treatment: Antibiotic-containing wastewater is pumped in from the bottom of the main body, then treated sequentially by the anaerobic zone and the aerobic zone, and finally discharged from the top of the main body.

2. The method for treating antibiotic wastewater and controlling the spread of ARGs using a microalgae filter bed coupled with a microbial fuel cell system according to claim 1, characterized in that: The first activated carbon layer (3) and the second activated carbon layer (7) are respectively filled with activated carbon, and the particle size of the activated carbon is 1-2 mm.

3. The method for treating antibiotic wastewater and controlling the spread of ARGs using a microalgae filter bed coupled with a microbial fuel cell system according to claim 1, characterized in that: Both the anode electrode (4) and the cathode electrode (8) include two interlayers and a hydrophilic graphite carbon felt, with the hydrophilic graphite carbon felt disposed between the two interlayers.

4. The method for treating antibiotic wastewater and controlling the spread of ARGs using a microalgae filter bed coupled with a microbial fuel cell system according to claim 1, characterized in that: The main body is provided with an inlet pipe (1) and an outlet pipe (12). The inlet pipe (1) is located at one end of the main body near the supporting layer (2), and the outlet pipe (12) is located at one end of the main body near the aerobic zone.

5. The method for treating antibiotic wastewater and controlling the spread of ARGs using a microalgae filter bed coupled with a microbial fuel cell system according to claim 1, characterized in that: In step S2, the hydraulic residence time is 48 hours.

Images