Method and device for treating fluoroquinolone antibiotics in wastewater solution

Abstract

The present invention discloses a method and apparatus for treating fluoroquinolone antibiotics in wastewater solutions. The apparatus comprises: a microwave generating component, including a magnetron for generating microwaves; a microwave testing component, including a circulator, a water load, a dual directional coupler, and a microwave power meter; a microwave plasma generating component, including a compression waveguide, a quartz tube, and a working gas loading tank; and a microwave plasma treatment component. The present invention addresses the problems of plasma instability caused by electrode corrosion, short device life, and secondary pollution caused by the introduction of new reagents or catalysts in existing plasma technologies. The microwave plasma generated by the apparatus of the present invention removes norfloxacin, a representative of the fluoroquinolone class, from wastewater. The degradation efficiency is 98.27±1.03% when the treatment time is 6 minutes, and the mineralization rate reaches 68.66±3.21% when the treatment time is 15 minutes.

Description

Technical Field

[0001] The invention belongs to the technical field of sewage treatment, and in particular relates to a method and a device for treating fluoroquinolone antibiotics in wastewater solution. Background Art

[0002] Antibiotics are natural or synthetic chemicals used to combat pathogenic microorganisms and are widely used in medicine, livestock farming, and pharmaceutical production. Fluoroquinolone antibiotics (FQs) are quinolones containing fluorine atoms. As chemically stable compounds, antibiotics are not fully absorbed by the body. An estimated 50%-90% of these antibiotics are excreted in feces or urine as parent compounds or metabolites, ultimately entering the aquatic environment. Researchers have detected antibiotic residue concentrations ranging from 0.5 ng / L to 30 mg / L in various water matrices. Antibiotics that confer bacterial resistance, when introduced directly or indirectly into water bodies, can cause long-term, irreversible effects on the microbial resistome. When the rate of antibiotic product renewal cannot keep pace with the mutation rate of pathogens, widespread viral infections are inevitable. Therefore, efficient wastewater treatment technologies are urgently needed to address the growing problem of antibiotic residues.

[0003] Conventional wastewater treatment processes mainly include physical, biological and chemical methods. However, these methods are not effective in dealing with high-concentration antibiotic wastewater or deep treatment of low-concentration antibiotic wastewater. At present, non-thermal plasma technologies (NTPs) technology is a new advanced oxidation process (AOPs) that can effectively degrade organic matter in wastewater and the atmosphere. NTPs induce various physical and chemical effects in liquids or at the gas-liquid interface. The physical effects involve electric fields, high-energy electrons, ultraviolet radiation and shock waves; the chemical effects produce reactive oxygen species (ROS), including ·OH, O·, H·, H2O2 and O3. These active species have been shown to have certain application prospects in the removal of FQs. Existing literature 1 (Xu et al., 2020.Degradation effect and mechanism of gas-liquid phase dielectric barrier discharge on norfloxacincombined with H2O2 or Fe 2+ .Separation and Purification Technology 230) uses gas-liquid DBD plasma to combine different catalysts (H2O2 or Fe 2+) to achieve degradation, DBD / H2O2(0.5mmol / L) / Fe 2+A combined system (10 mg / L) achieved a 98% degradation efficiency after just 0.5 minutes at a discharge power of 60 W. However, this method suffers from the threat of plasma stability from electrode corrosion and vapor contamination, significantly reducing its service life, and the degraded target solution can be recontaminated by particles released from the corroded electrodes. Reference 2 (Santos et al., 2015. Degradation of the antibiotic norfloxacin by Fenton, UV and UV / H2O2. J Environ Manage 154, 8-12) employed direct photolysis (ultraviolet: UV), photolysis combined with hydrogen peroxide (UV / H2O2), and Fenton oxidation to degrade NOR. The results demonstrated that direct photolysis (either at 273 nm or 320 nm) was unfeasible. Although the degradation efficiency reached 85%, the reaction time was 7 hours, and the mineralization rate was only 2%. Combining Fenton oxidation with ultraviolet light or H₂O₂ removes NOR from solution, achieving a degradation efficiency of 100% in 100 minutes and 60% in 60 minutes, with mineralization efficiencies reaching 55% and 32%, respectively. The disadvantages of this method are that UV lamps are not only expensive, but the heavy metals in discarded lamps also pose a serious environmental pollution risk, making their disposal difficult, the reaction time long, and the mineralization efficiency relatively low. Furthermore, new pollutant reagents (combining Fenton technology with catalysts or UV photolysis) are required. Reference 3 (Chen et al., 2017. Synthesis of MnOx / SBA-15 for Norfloxacin Degradation by Catalytic Oxonation. Separation and Purification Technology 173, 99-104) compared the degradation of NOR using ozone (O₃), a SBA-15 / O₃ catalyst system, and a MnOx / SBA-15 / O₃ composite catalyst system. All three processes achieved NOR removal efficiencies exceeding 90% within 15 minutes, indicating that the addition of a catalyst had little effect on the efficiency of ozone degradation. However, within 60 minutes, the combined MnOx / SBA-15 catalyst and ozone system increased the mineralization efficiency to 54%, 1.36 times that of the ozone process alone. The disadvantages of this method are: ozone and organic compounds typically produce aldehydes and carboxylic acids during the reaction, which inhibit further reactions; ozone oxidation reactions are selective and slow; and the catalyst processing involves the addition of multiple chemicals, a complex process, and a time-consuming, high failure rate. This increases the risk of secondary pollution and the experimental cost. Summary of the Invention

[0004] The purpose of the present invention is to provide a method and device for treating fluoroquinolone antibiotics in wastewater solutions, so as to solve the problems of plasma instability caused by electrode corrosion, short device life, and secondary pollution caused by the introduction of new reagents or catalysts in existing plasma technology.

[0005] In order to achieve the above object, the present invention provides a device for treating fluoroquinolone antibiotics in wastewater, the device comprising:

[0006] A microwave generating component for generating microwaves; a microwave testing component for adjusting the microwave power generated by the microwave generating component to output microwaves meeting the required power; a microwave plasma generating component for generating microwave plasma through working gas and the microwaves output by the microwave testing component; and a microwave plasma treating component for treating the wastewater contained therein using the microwave plasma generated by the microwave plasma generating component to degrade fluoroquinolone antibiotics in the wastewater. The microwave generating component includes a magnetron; the microwave testing component includes a circulator, a water load, and a dual-directional coupler; one end of the circulator is connected to the magnetron, the other end is connected to the water load, and the remaining end is connected to one end of the dual-directional coupler; the microwave plasma generating component includes a compression waveguide, a quartz tube, and a working gas loading tank; the input end of the compression waveguide is connected to the output end of the dual-directional coupler, the compression waveguide is inserted into the cavity of the compression waveguide, and the working gas in the working gas loading tank is connected to the cavity of the quartz tube through a pipe; the microwave plasma processing component includes a reactor; the reactor is filled with wastewater containing the fluoroquinolone antibiotics; the quartz tube is placed vertically in the reactor, and the bottom of the quartz tube does not contact the liquid surface in the reactor.

[0007] Preferably, the microwave plasma generating component further includes a mass flow controller for adjusting the flow rate of the working gas, one end of the mass flow controller is connected to the working gas loading tank through a pipeline, and the other end is connected to the interior of the quartz tube.

[0008] Preferably, the working gas is argon.

[0009] Preferably, the microwave testing component further includes a microwave power meter for measuring the output and input power of the dual-directional coupler; a first interface of the microwave power meter is connected to the incident port of the dual-directional coupler through a probe, for measuring the input power of the dual-directional coupler; a second interface of the microwave power meter is connected to the reflection port of the dual-directional coupler through a probe, for measuring the output power of the dual-directional coupler.

[0010] Preferably, the microwave plasma treatment component further comprises a magnetic stirrer and a water-cooled circulator; the magnetic stirrer is used to stir the liquid in the reactor; the water-cooled circulator is used to control the reaction temperature of the reactor;

[0011] More preferably, a cooling layer is provided on the periphery of the reactor, the lower water inlet of the cooling layer is connected to the water outlet of the water cooling circulator, and the upper water outlet is connected to the water inlet of the water cooling circulator; a magnetic stirrer is placed in the reactor, and the solution in the reactor is stirred by the magnetic particle stirrer.

[0012] Preferably, the outer diameter of the quartz tube is 15 mm and the inner diameter is 14 mm; the flow rate of the working gas passing through the quartz tube is 6 to 12 L / min.

[0013] The invention provides a method for treating fluoroquinolone antibiotics in wastewater solution, which uses microwave plasma to degrade the fluoroquinolone antibiotics in the wastewater solution.

[0014] Preferably, the microwave plasma is generated by the device, and the method comprises:

[0015] (1) adding the wastewater containing fluoroquinolone antibiotics into the reactor;

[0016] (2) Turn on the power switch of the magnetron, adjust the power of the microwave generated by the magnetron through the microwave test component, and then introduce the output microwave into the quartz tube through the compression waveguide;

[0017] (3) Turn on the switch of the working gas loading tank, and the working gas in the working gas loading tank is sent into the quartz tube after the flow rate is adjusted by the mass flow controller;

[0018] (4) By introducing stable microwaves and working gas into the quartz tube, microwave plasma is synthesized inside the tube, and the microwave plasma is injected into the reactor to degrade the fluoroquinolone antibiotics in the reactor; at the same time, a water cooling circulator is started to control the temperature of the reactor; and a magnetic stirrer is started to stir the wastewater in the reactor to accelerate the reaction rate.

[0019] Preferably, the pH of the wastewater is 2-11.

[0020] The method and apparatus of the present invention for treating fluoroquinolone antibiotics in wastewater solve the problems of plasma instability and short device life caused by plasma electrode corrosion in the prior art, as well as secondary pollution caused by the introduction of new reagents or catalysts, and have the following advantages:

[0021] 1. The electrodes of arc plasma generators in the prior art are corroded by other gases, such as oxygen, chlorine, and air, and the continuous life of the generator does not exceed 200 hours. The device of the present invention does not require the use of metal electrodes, synthetic catalysts, or the addition of additional chemical reagents, and does not have the problem of electrode corrosion. The plasma generated is extremely pure and has a service life of approximately 10,000 to 20,000 hours.

[0022] 2. Compared with the prior art, the quartz tube in the device of the present invention is inserted into the cavity of the compression waveguide and placed vertically in the reactor, and the bottom does not contact the liquid surface in the reactor, thereby achieving the goal of a low-cost magnetron to generate stable, high-throughput microwave plasma.

[0023] 3. Compared with the prior art, the present invention is the first to use microwave plasma generated by the device to remove norfloxacin, a representative of fluoroquinolones, from wastewater.

[0024] 4. The device of the present invention uses a quartz tube with an inner diameter of 14 mm and an outer diameter of 15 mm, and introduces argon at a flow rate of 8 L / min. When the generated argon microwave plasma is used to treat a norfloxacin solution with an initial concentration of 20 mg / L and a volume of 50 mL, the degradation efficiency is 98.27±1.03% when the treatment time is 6 minutes, and the mineralization rate reaches 68.66±3.21% when the treatment time is 15 minutes. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the device for treating fluoroquinolone antibiotics in wastewater solution according to the present invention (1).

[0026] Figure 2 Schematic diagram of the device for treating fluoroquinolone antibiotics in wastewater solution according to the present invention (II).

[0027] Figure 3 This is a diagram showing the degradation principle of fluoroquinolone antibiotics in wastewater solution treated by the device for treating fluoroquinolone antibiotics in wastewater solution of the present invention.

[0028] Label: 1. Microwave generating component; 10. Magnetron; 2. Microwave testing component; 21. Circulator; 22. Water load; 23. Microwave power meter; 24. Dual directional coupler; 3. Microwave plasma generating component; 31. Compression waveguide; 32. Quartz tube; 33. Working gas loading tank; 34. Mass flow controller; 4. Microwave plasma processing component; 41. Reactor; 42. Magnetic stirrer; 43. Water-cooled circulator. DETAILED DESCRIPTION

[0029] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0030] The models and manufacturers of the instruments involved in the following embodiments are as follows:

[0031] DC magnetron power supply: DDY10-5K / 0V8-S220 / F02, Sichuan Yingjiete Electric Co., Ltd., China;

[0032] Box magnetron 10: Panasonic 2M244-M1;

[0033] Circulator 21: Euler, CIWG26-2450-1KWA101010;

[0034] Water load 22: MPHNWG26WLA01-1KW;

[0035] Microwave power meter 23: AV2433;

[0036] Dual directional coupler 24: Euler, LOOP26DC40D20A10N;

[0037] Compression waveguide 31: Euler, LAWG26A10;

[0038] Quartz tube 32: outer diameter 15mm, inner diameter 14mm, custom-made by Siboda Quartz;

[0039] Mass flow controller 34: KT-C27, Zhengzhou Ketan Instrument Equipment Co., Ltd., China;

[0040] Reactor 41: Double-layer jacketed beaker, custom-made by Siboda quartz;

[0041] Magnetic stirrer 42: MS-1A, power 20W, maximum stirring volume 5L, size 210*160*85 (mm), Runyu Science;

[0042] Water-cooled circulator 43: HS1500-LAS1-001A, specifications 480*360*580 (mm), Shenzhen Hongsen Jingke Industrial Co., Ltd.

[0043] Example 1

[0044] A device for treating fluoroquinolone antibiotics in wastewater solution, such as Figure 1As shown in FIG. 1 , a schematic diagram of a device for treating fluoroquinolone antibiotics in a wastewater solution according to the present invention is shown in FIG. Figure 2 As shown, the schematic diagram of the device for treating fluoroquinolone antibiotics in wastewater solution of the present invention (II) is shown, and the device comprises:

[0045] Microwave generating component 1, microwave testing component 2, microwave plasma generating component 3, microwave plasma processing component 4.

[0046] The microwave generating component 1 is a box-type magnetron 10 (microwave power is 200W, low power and low energy consumption), and a direct current (DC) magnetron power supply provides electrical energy and anode current to excite the box-type magnetron 10 to generate microwaves.

[0047] The microwave test component 2 includes a circulator 21, a water load 22 for the circulator, a microwave power meter 23, and a dual-directional coupler 24, which are used to adjust the microwave power generated by the microwave generating component 1 to output microwaves that meet the required power. The circulator 21 is used to separate the injected and reflected microwave signals. One end of the circulator is connected to the magnetron 10, and the reflected microwave signal is absorbed by the water load 22 connected to the circulator 21. The dual-directional coupler 24 is used to measure the output power and spectrum. One end of the dual-directional coupler is connected to the other end of the circulator 21. The first interface of the microwave power meter 23 is connected to the incident port of the dual-directional coupler 24 via a probe to measure the input power of the dual-directional coupler 24. The second interface of the microwave power meter 23 is connected to the reflection port of the dual-directional coupler 24 via a probe to measure the output power of the dual-directional coupler 24.

[0048] The microwave plasma generating component 3 includes a compression waveguide 31, a quartz tube 32, a working gas loading tank 33 and a mass flow controller 34, and is used to generate microwave plasma through the working gas and the microwave output by the microwave testing component 2; wherein the working gas in the working gas loading tank 33 is flow-controlled by the mass flow controller 34 and then introduced into the upper end of the quartz tube 32; the input end of the compression waveguide 31 is connected to the other end (output end) of the dual directional coupler 24 for extracting the microwave generated by the magnetron 10, and the output end of the compression waveguide 31 is provided with a hole for inserting the quartz tube 32, for inserting the quartz tube 32, for introducing the microwave in the compression waveguide 31 into the quartz tube 32, and the quartz tube 32 is inserted into the quartz tube 32. The dimensions of the tube 32 match the aperture of the compression waveguide 31, forming a TE10 mode in the compression waveguide 31 (when the compression section length of the waveguide is designed to be 80 mm and the terminal gap height is 1 mm, the reflection within the cavity can reach a minimum value of -10 dB, allowing more microwave energy to be transmitted at the terminal to produce a stable, linear plasma). The working gas is argon, which has a dielectric strength of 0.18, much lower than that of air 1. Furthermore, argon plasma is relatively pure and does not produce harmful gases, such as NOx and O3, like air plasma. The microwave plasma is ejected from the quartz tube 32. The microwave plasma has a length of approximately 5 mm, an inner diameter of approximately 14 mm, and a cross-sectional area of ​​approximately 153 mm. 2 .

[0049] Microwave plasma treatment unit 4 comprises a reactor 41, a magnetic stirrer 42, and a water-cooled circulator 43. It utilizes the microwave plasma generated by microwave plasma generation unit 3 to treat the wastewater contained therein, thereby degrading the fluoroquinolone antibiotics in the wastewater. The lower water inlet of the outer layer of reactor 41 (a custom-made double-layer structure, with the inner layer containing the solution) is connected to the outlet of water-cooled circulator 43, while the upper water outlet of the outer layer of reactor 41 is connected to the inlet of water-cooled circulator 43. Cold water from water-cooled circulator 43 enters the outer layer of reactor 41 through the lower water inlet and then flows back into water-cooled circulator 43 through the upper water outlet, providing a circulating condensation effect and controlling the reaction temperature of reactor 41. A quartz tube 32 is placed vertically within reactor 41, with its bottom not in contact with the liquid level in reactor 41. The reactor 41 is placed on a magnetic stirrer 42. The reactor 41 is filled with wastewater containing the fluoroquinolone antibiotics and is provided with a magnetic stirrer. The solution in the reactor 41 is stirred by the magnetic stirrer. The stirring speed is controlled to prevent the solution from leaking, while achieving a full and uniform reaction effect.

[0050] The method for treating fluoroquinolone antibiotics in wastewater solution by the above-mentioned device for treating fluoroquinolone antibiotics in wastewater solution is as follows: Figures 1-2 As shown, the method includes:

[0051] (1) Adding norfloxacin solution into reactor 41 (initial concentration of NOR solution is 20 mg / L, volume is 50 mL, pH is 4);

[0052] (2) Turn on the power switch of the magnetron 10. The generated microwaves are separated by the circulator 21 of the microwave test component 2, measured by the dual directional coupler 24, and displayed by the microwave power meter 23 (to detect whether the microwaves output by the magnetron 10 meet the requirements). The microwaves are then introduced into the quartz tube 32 (the outer diameter of the quartz tube is 15 mm and the inner diameter is 14 mm) through the compression waveguide 31.

[0053] (3) Turn on the switch of the working gas loading tank 33. The working gas in the working gas loading tank 33 is regulated by the mass flow controller 34 and then sent into the upper port of the quartz tube 32 (the argon flow rate is 8 L / min);

[0054] (4) The microwaves entering the quartz tube 32 and the working gas fed into the upper end of the quartz tube 32 synthesize microwave plasma and are ejected (P = 200 W, the length of the microwave plasma is about 5 cm, the diameter is about 7 mm, and the volume is about 7650 cubic millimeters). The microwave plasma is injected into the reactor 41 containing the fluoroquinolone antibiotic solution to degrade the antibiotic (basically all of the microwave plasma is injected into the norfloxacin solution). The fluoroquinolone antibiotic solution is stirred at a rate controlled by a magnetic stirrer 42 through a magnetic particle stirrer therein, and the reaction temperature is controlled by a water-cooled circulator 43.

[0055] When the treatment time was 6 minutes, the degradation efficiency was 98.32±0.86%.When the treatment time was 15 minutes, the degradation efficiency reached 99.59±0.51% (pH=4), and the mineralization rate reached 68.66±3.21%.

[0056] like Figure 3 As shown in FIG, the degradation principle diagram of the fluoroquinolone antibiotics in wastewater solution by the device for treating fluoroquinolone antibiotics in wastewater solution of the present invention. Figure 3 It can be clearly seen that the gas phase (first layer) is ·OH, ·O, etc.; the gas-liquid phase (second layer) is water decomposing into ·OH and ·H; and the norfloxacin solution (third layer) is ·OH acting on the CF bond, carboxyl group, etc. in NOR.

[0057] The above-mentioned free radical scavenger (·OH) experiment showed that ·OH is the main active substance in NOR degradation. By using HPLC-Q-TOF / MS to detect intermediate products, the possible pathways of NOR degradation were determined. Oxidation mainly causes the CF bond of the benzene ring to be replaced by a hydroxyl group to C-OH, as well as the opening and cleavage of piperazine, quinolone and even benzene rings, leading to transformation. Therefore, there are three main possible degradation pathways: the first is the cleavage of the piperazine group; the second is the opening of the quinolone and benzene ring and the shedding of the piperazine group, through the treatment of organic macromolecules to small organic molecules through microwave plasma jet, and even mineralization into inorganic ions (F - 、NO 3- , CO2 and H2O); the third one is decarboxylation, defluorination and demethylation, which is the main reaction.

[0058] Example 2

[0059] A device for treating fluoroquinolone antibiotics in wastewater is the same as that in Example 1.

[0060] The method for treating fluoroquinolone antibiotics in wastewater solution using the above-mentioned device for treating fluoroquinolone antibiotics in wastewater solution is basically the same as that in Example 1, except that:

[0061] When the argon flow rate (gas flow rate) was 6, 10 and 12 L / min, the degradation efficiency was 35.0%, 57.6% and 48.8%, respectively.

[0062] When the gas flow rate is too low, microwave plasma is not conducive to the generation of high-energy electrons and active oxidative species in surface discharge, which directly reduces the degradation efficiency of NOR solution; however, when the gas flow rate is too high, the residence time of free radicals is reduced, and the residence time of free radicals is reduced, and they cannot react completely with the pollutants, thereby reducing the degradation efficiency.

[0063] Example 3

[0064] A device for treating fluoroquinolone antibiotics in wastewater is the same as that in Example 1.

[0065] The method for treating fluoroquinolone antibiotics in wastewater solution using the above-mentioned device for treating fluoroquinolone antibiotics in wastewater solution is basically the same as that in Example 1, except that:

[0066] When the pH of norfloxacin solution was 2, 7 and 11, the degradation efficiency of NOR solution after treatment for 6 minutes was 49.25±1.92%, 88.76±2.38% and 73.37±1.92%, respectively; when the treatment time was 15 minutes, the degradation efficiency was 90.89±1.45%, 98.5±1.19% and 94.78±1.50%, respectively.

[0067] The experimental results of Examples 1 and 2 indicate that the pH value of the solution is a key parameter that influences the type and quantity of ROS (chemically generated reactive oxygen species) generated during the discharge plasma process, as well as the type of organic compounds in the aqueous phase. At pH values ​​of 2, 4, 7, and 11, the degradation efficiency of the NOR solution after 6 minutes of treatment was 49.25±1.92%, 98.32±0.86%, 88.76±2.38%, and 73.37±1.92%, respectively. At a treatment time of 15 minutes, the degradation efficiency was 90.89±1.45%, 99.59±0.51%, 98.5±1.19%, and 94.78±1.50%, respectively. Therefore, the pH values ​​corresponding to the degradation efficiency of the NOR solution, from highest to lowest, are: pH = 4 > pH = 7 > pH = 11 > pH = 2. It is generally believed that acidic conditions are more conducive to the complete degradation of organic matter into small inorganic molecules. However, in strongly acidic solutions, such as those at pH 2, NOR (norfloxacin) is protonated almost entirely in the cationic form (NOR + ,0). When the proton combines with the N4 of the piperazine group, NOR becomes positively charged, which results in a decrease in its reactivity to free radicals. The oxidation potential of ˙OH is greatly affected by the pH value of the solution. A high pH value will result in a low oxidation potential of ˙OH because OH - It is easy to react with ˙OH, thus weakening its ability to attack NOR molecules. Therefore, the degradation effect of fluoroquinolone antibiotics in wastewater treated by the above device is better when the pH value is 4.

[0068] Although the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description is not intended to limit the present invention. After reading the above description, various modifications and substitutions of the present invention will become apparent to those skilled in the art. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A device for treating fluoroquinolone antibiotics in wastewater, characterized in that: The device contains: A microwave generating component (1) for generating microwaves; The microwave testing component (2) is used to adjust the microwave power generated by the microwave generating component (1) to output microwaves that meet the required power; A microwave plasma generating component (3) for generating microwave plasma through working gas and microwaves output by the microwave testing component (2); A microwave plasma treatment component (4) is used to treat the wastewater contained therein using the microwave plasma generated by the microwave plasma generating component (3) to degrade fluoroquinolone antibiotics in the wastewater; The microwave generating component (1) includes a magnetron (10); The microwave test component (2) includes a circulator (21), a water load (22), a dual directional coupler (24), and a microwave power meter (23) for measuring the output and input power of the dual directional coupler (24); One end of the circulator (21) is connected to the magnetron (10), the other end is connected to the water load (22), and the remaining end is connected to one end of the dual directional coupler (24); The first interface of the microwave power meter (23) is connected to the incident port of the dual-directional coupler (24) through a probe, and is used to measure the input power of the dual-directional coupler (24); the second interface is connected to the reflection port of the dual-directional coupler (24) through a probe, and is used to measure the output power of the dual-directional coupler (24); The microwave plasma generating component (3) comprises a compression waveguide (31), a quartz tube (32), and a working gas loading tank (33); the input end of the compression waveguide (31) is connected to the output end of the dual directional coupler (24), the quartz tube (32) is inserted into the cavity of the compression waveguide (31), and the working gas in the working gas loading tank (33) is connected to the cavity of the quartz tube (32) through a pipeline; The microwave plasma treatment component (4) includes a reactor (41); the reactor (41) is filled with wastewater containing the fluoroquinolone antibiotic; the quartz tube (32) is vertically placed in the reactor (41), and the bottom of the quartz tube (32) does not contact the liquid surface in the reactor (41); The outer diameter of the quartz tube (32) is 15 mm and the inner diameter is 14 mm; The working gas is argon; The circulator (21) is used to separate and inject reflected microwave signals, and the reflected microwave signals are absorbed by a water load (22) connected to the circulator (21); A TE10 mode is formed in the compression waveguide (31), the compression section length of the compression waveguide (31) is 80 mm, the terminal gap height is 1 mm, and the minimum reflection value in the cavity is -10 dB.

2. The device for treating fluoroquinolone antibiotics in wastewater according to claim 1, characterized in that: The microwave plasma generating component (3) further includes a mass flow controller (34) for adjusting the flow of the working gas, one end of the mass flow controller (34) being connected to the working gas loading tank (33) through a pipeline, and the other end being connected to the interior of the quartz tube (32).

3. The device for treating fluoroquinolone antibiotics in wastewater according to claim 1, characterized in that: The microwave plasma treatment component (4) further includes a magnetic stirrer (42) and a water cooling circulator (43); The magnetic stirrer (42) is used to stir the liquid in the reactor (41); and the water-cooling circulator (43) is used to control the reaction temperature of the reactor (41).

4. The device for treating fluoroquinolone antibiotics in wastewater according to claim 3, characterized in that: A cooling layer is provided on the periphery of the reactor (41), the lower water inlet of the cooling layer is connected to the water outlet of the water-cooled circulator (43), and the upper water outlet of the cooling layer is connected to the water inlet of the water-cooled circulator (43); a magnetic stirrer is placed in the reactor (41), and the solution in the reactor (41) is stirred by the magnetic stirrer.

5. The device for treating fluoroquinolone antibiotics in wastewater according to claim 1, characterized in that: The flow rate of the working gas in the quartz tube (32) is 6-12 L / min.

6. A method for treating fluoroquinolone antibiotics in wastewater solution, characterized in that: Degradation of fluoroquinolone antibiotics in wastewater solution using microwave plasma; The microwave plasma is generated by the device according to any one of claims 1 to 5, and the method comprises: (1) adding wastewater containing fluoroquinolone antibiotics into the reactor (41); (2) turning on the power switch of the magnetron (10), regulating the power of the microwave generated by the magnetron (10) through the microwave test component (2), and then introducing the output microwave into the quartz tube (32) through the compression waveguide (31); (3) The switch of the working gas loading tank (33) is turned on, and the working gas in the working gas loading tank (33) is fed into the quartz tube (32) after the flow rate is regulated by the mass flow controller (34); (4) Microwaves and working gas are introduced into the quartz tube (32) to synthesize microwave plasma therein, and the microwave plasma is injected into the reactor (41) to degrade the fluoroquinolone antibiotics in the reactor (41); at the same time, a water cooling circulator (43) is started to control the temperature of the reactor (41); and a magnetic stirrer (42) is started to stir the wastewater in the reactor (41) to accelerate the reaction rate.

7. The method according to claim 6, characterized in that The pH of the wastewater is 2-11.

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