A disinfection method for simultaneously removing antibiotics, drug-resistant bacteria and resistance genes in water and reducing disinfection by-products

Abstract

The present invention discloses a disinfection method for simultaneously removing antibiotics, drug-resistant bacteria and resistance genes in water and reducing disinfection by-products, belonging to the technical field of sewage treatment. The steps of the disinfection method include: adding sodium hypochlorite to the water to be disinfected to ensure that the concentration of effective chlorine in the water to be disinfected is 2 to 15 mg / L; further introducing DO through aeration and performing VUV disinfection to simultaneously remove antibiotics, drug-resistant bacteria and resistance genes in the water to be disinfected and reduce disinfection by-products. The present invention uses aeration-coupled VUV / NaClO technology for deep treatment of reclaimed water, which can efficiently inactivate microorganisms and prevent their resurrection, effectively remove ARGs, control horizontal gene transfer, and at the same time degrade residual antibiotics, completely blocking the spread of bacterial resistance, and effectively ensuring the safety of reclaimed water quality.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment, and in particular relates to a disinfection method for simultaneously removing antibiotics, drug-resistant bacteria and resistance genes in water and reducing disinfection by-products. Background Art

[0002] Driven by climate change, population growth, and economic development, global water demand and wastewater generation are increasing annually. Freshwater scarcity, water pollution, and ecological damage to the aquatic environment are major challenges to sustainable development. Municipal wastewater generation is large, but both quantity and quality are relatively stable. Treating and reusing wastewater to meet standards is a key approach to addressing the current water crisis. Currently, unconventional water sources such as recycled water are serving as a "secondary water source" in some water-scarce cities, supplementing conventional water resources. Improving wastewater treatment efficiency and accelerating the development and utilization of recycled water will play a significant role in alleviating the imbalance between water supply and demand.

[0003] Compared to conventional water resources like surface water and groundwater, wastewater has complex water quality, containing higher concentrations of pathogenic microorganisms and chemical pollutants. The extensive use and misuse of antibiotics has led to widespread antibiotic residues in wastewater, as well as the emergence of numerous antimicrobial-resistant bacteria (ARBs) and resistance genes (ARGs). Improper treatment can pose serious health and ecological risks. Therefore, ensuring the safety of recycled water quality is a crucial prerequisite for promoting wastewater resource utilization. In water treatment, disinfection plays a crucial role in inactivating pathogens and preventing the spread of disease, and is the final barrier to ensuring the safety of recycled water.

[0004] Currently, the most commonly used recycled water disinfection technologies include chlorine disinfection and ultraviolet (UV) disinfection, both of which have defects to varying degrees:

[0005] (1) Chlorine disinfection is low-cost and simple in process, and residual chlorine can maintain continuous disinfection ability. However, chlorine disinfection will produce a large number of disinfection by-products (DBPs) with "tri-toxic" toxicity and induce the formation of chlorine-resistant bacteria, such as Pseudomonas, Coleus and Acinetobacter. Moreover, a large number of studies have shown that under the commonly used chlorine doses in water disinfection processes, chlorine disinfection not only cannot effectively destroy ARGs, but also promotes the release of intracellular ARGs to the extracellular space, increases the frequency of horizontal transfer of ARGs, and increases the risk of bacterial resistance.

[0006] (2) UV disinfection equipment is simple and does not require the addition of chemicals. It can directly destroy the DNA of bacteria and has the potential to remove ARGs in water bodies. However, UV disinfection does not have the ability to continuously disinfect, and some bacteria are not completely killed after UV disinfection. They enter a viable but non-culturable state (VBNC) and can be revived when external conditions are suitable. This still poses a serious health risk.

[0007] (3) Chlorine disinfection and ultraviolet disinfection, two conventional water disinfection processes, have poor removal effects on antibiotics. Although they can kill ARBs, the resulting cell fragments still contain intact DNA fragments. These DNA fragments can spread resistance to downstream bacterial populations through natural transformation or conjugation and transduction. At the same time, residual antibiotics can also induce the production of new drug-resistant bacteria. Wastewater treatment plants have become a reservoir of ARBs and ARGs.

[0008] (4) The combined disinfection process of ultraviolet and chlorine (UV / NaClO) produces a large number of active oxidizing substances such as chlorine radicals (Cl·) and hydroxyl radicals (·OH) by UV-stimulating low-dose NaClO. This can significantly improve the bacterial inactivation rate, inhibit bacterial resurrection, enhance the degradation of pollutants such as antibiotics, greatly reduce the amount of chemical agents used, and make up for the shortcomings of a single disinfection process. It has been widely used in the treatment of drinking water, wastewater, and recycled water. However, the chlorine radicals (Cl·) produced in the UV / NaClO system will react with organic matter, resulting in an increase in the production of DBPs. Among them, the increase in the production of nitrogen-containing DBPs with higher toxicity, such as halogenated acetonitriles, is more significant, resulting in a significant increase in the risk of disinfection. In addition, many studies have shown that the removal effect of the UV / NaClO system on ARGs is unstable. Summary of the Invention

[0009] In order to overcome the defects of the prior art in water disinfection, the present invention provides a disinfection method for simultaneously removing antibiotics, drug-resistant bacteria and resistance genes in water and reducing disinfection by-products.

[0010] To achieve the above object, the present invention provides the following technical solutions:

[0011] One of the technical solutions of the present invention is to provide a disinfection method for simultaneously removing antibiotics, drug-resistant bacteria and resistance genes in water and reducing disinfection by-products, comprising the following steps:

[0012] Sodium hypochlorite is added to the water to be disinfected to ensure that the concentration of effective chlorine in the water to be disinfected is 2-15 mg / L; dissolved oxygen (DO) is further introduced through aeration and vacuum ultraviolet light (VUV) disinfection is performed to simultaneously remove antibiotics, drug-resistant bacteria and resistance genes in the water to be disinfected and reduce disinfection by-products.

[0013] The present invention utilizes the DO provided by aeration to strengthen the VUV catalytic reaction of low-concentration free chlorine in water, greatly increasing the production of oxidative active substances such as O3, hydroxyl radicals and active chlorine radicals, which can significantly improve the oxidation capacity of the system, strengthen the degradation of difficult-to-degrade organic matter such as antibiotics, increase the degree of structural damage to microorganisms such as bacteria and resistance genes, block bacterial resurrection and DNA repair function, efficiently remove antibiotics, ARBs, ARGs, control horizontal gene transfer, and completely block the spread of antibiotic resistance in water.

[0014] The present invention controls the concentration of effective chlorine to 2-15 mg / L, which can ensure the disinfection effect and avoid the pollution of the environment caused by excessive chlorine.

[0015] The VUV (10-195 nm) used in this invention has a higher energy density than traditional UV (254 nm). The active chlorine species produced by VUV-excited NaClO are primarily chlorine oxide radicals (ClO·), rather than Cl·. Unlike the substitution reaction of Cl·, ClO· reacts with organic matter primarily through electron transfer, effectively avoiding the production of halogenated disinfection byproducts (DBPs). Therefore, replacing traditional UV with VUV to construct a VUV / NaClO advanced oxidation system for reclaimed water disinfection can effectively control the risk of DBPs.

[0016] Preferably, the aeration rate is 0.3-1 mL / min.

[0017] Preferably, the VUV irradiation dose is 300 to 1000 mJ / cm 2 .

[0018] Preferably, the aeration is achieved through a microporous aeration membrane with a diameter of 0.1 to 5 μm.

[0019] More preferably, the microporous aeration membrane is made of ceramic.

[0020] Traditional organic micro-nano aeration membranes are easily corroded and damaged by chlorine, oxidative free radicals, and have a short service life. The ceramic membranes of the present invention offer advantages such as small, high-volume bubble production, large effective area, and high oxygen dissolution efficiency. They also possess unique advantages such as resistance to fouling and clogging, ease of cleaning, acid and alkali resistance, oxidation resistance, high temperature resistance, high strength, resistance to damage, and a long service life. The micro-nano aeration process based on the aeration membranes of the present invention can increase dissolved oxygen levels in water with relatively low energy consumption.

[0021] Preferably, the chemical oxygen demand (COD) and ammonia nitrogen of the water to be disinfected are tested before adding sodium hypochlorite. When the COD in the water to be disinfected is ≤50 mg / L and the ammonia nitrogen is ≤8 mg / L, the amount of chlorine added is 5-15 mg / L; when 50<COD≤60 mg / L and 5<ammonia nitrogen≤15 mg / L in the water to be disinfected, the amount of chlorine added is 8-20 mg / L.

[0022] The present invention establishes a prediction model for the removal effect of antibiotics, bacteria and drug-resistant genes through a back propagation neural network (BPNN), and constructs a chlorine dosage control model based on BPNN model machine learning. The model determination coefficient is 0.9531, and the chlorine dosage is calculated in Cl2.

[0023] The second technical solution of the present invention is to provide an application of the above-mentioned disinfection method for simultaneously removing antibiotics, drug-resistant bacteria and resistance genes in water and reducing disinfection by-products in sewage treatment.

[0024] The beneficial technical effects of the present invention are as follows:

[0025] The disinfection method provided by the present invention for simultaneously removing antibiotics, drug-resistant bacteria and resistance genes in water and reducing disinfection by-products couples free chlorine with vacuum ultraviolet irradiation and aeration technology. By regulating the appropriate proportion and dosage of free chlorine and VUV irradiation, and with the help of the DO synergistic catalysis and hydraulic regulation of micro-nano aeration, the coupling effect of hydroxyl radicals, active chlorine radicals and ultraviolet photon radiation is achieved, thereby efficiently achieving disinfection and sterilization of reclaimed water and removal of difficult-to-degrade organic matter.

[0026] The disinfection method provided by the present invention can effectively inactivate UV-resistant cells (such as spores), chlorine-resistant bacteria and viruses, and can more thoroughly destroy pathogenic microorganisms, effectively preventing bacterial resurrection; in addition, the concentration and oxidizing capacity of highly active oxidizing substances produced by VUV activation are much higher than those of UV-activated products, and can effectively degrade highly toxic, difficult-to-degrade, and large-molecule organic matter in water, converting them into small-molecule organic matter, and even completely mineralizing them into carbon dioxide, thereby achieving efficient removal of pollutants.

[0027] The present invention uses an aeration-coupled VUV / NaClO process for deep treatment of reclaimed water, which can efficiently inactivate microorganisms and prevent their resurrection, effectively remove ARGs, control horizontal gene transfer, and degrade residual antibiotics, completely blocking the spread of bacterial resistance, thereby effectively ensuring the safety of reclaimed water quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a flow chart of the ceramic membrane micro-nano aeration coupled VUV / NaClO reclaimed water disinfection method in Example 1.

[0029] Figure 2 and Figure 3 This is a schematic diagram of the water purification and disinfection reactor in Example 1.

[0030] Figure 4 2 is a schematic three-dimensional diagram of the deflector 10 .

[0031] Figure 5 It is the bacteria removal rate of the scheme of Example 1 and Comparative Examples 1-4.

[0032] Figure 6 It is the antibiotic degradation rate of the scheme of Example 1 and Comparative Examples 1-4.

[0033] Figure 7 It is the sul1 gene removal rate of the scheme of Example 1 and Comparative Examples 1-4.

[0034] Figure 2 and Figure 3 In the figure, 1-upper plate, 2-quartz tube, 3-vacuum ultraviolet lamp, 4-support rod, 5-exhaust pipe, 6-blower, 7-aeration plate, 8-lower plate, 9-reactor shell, 10-flow guide, 11-liquid surface, (1-1)-air inlet, (4-1)-air outlet, (8-1)-opening, (9-1)-water outlet, (10-1)-water inlet. DETAILED DESCRIPTION

[0035] Various exemplary embodiments of the present invention are now described in detail. This detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terms used in the present invention are only for describing specific embodiments and are not intended to limit the present invention.

[0036] In addition, for numerical ranges in the present invention, it is understood that each intervening value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between any stated value or stated range, and any other stated value or intervening value in the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention pertains. Although preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention.

[0038] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0039] In the water quality automatic detection unit of the embodiment of the present invention and the comparative example, the COD value is monitored by a commercially available COD online automatic monitoring instrument. A certain amount of potassium dichromate is added to the water sample. In a strong acid medium, silver sulfate is used as a catalyst. After high temperature digestion, potassium dichromate is converted into hexavalent chromium (Cr 6+ ) is reduced to produce trivalent chromium (Cr 3+ ), COD concentration in water samples and hexavalent chromium (Cr 6 + ) reduction, trivalent chromium (Cr 3+) increases in proportion, and its absorbance is detected by the corresponding light source and then converted into the COD value of the water sample through software; the ammonia nitrogen value can be monitored by a conventional commercially available ammonia nitrogen online monitor. After the water sample and the masking agent are mixed, the ammonia nitrogen in the form of free ammonia or ammonium ions reacts with salicylate and hypochlorite ions in an alkaline environment and in the presence of a sensitizer to form a blue complex. The analyzer detects the photometric change of this color and converts it into an ammonia nitrogen value; the turbidity is measured using an online turbidity detector, which reflects the turbidity of water quality by measuring the degree of light scattering by suspended particles in water, and the degree of scattering is proportional to the turbidity; the color is monitored using an online colorimeter.

[0040] Example 1

[0041] Ceramic membrane micro-nano aeration coupled VUV / NaClO recycled water disinfection method:

[0042] 1) Recycled water first enters the automatic water quality testing unit. The online automatic monitoring platform measures COD, ammonia nitrogen, turbidity, and color, respectively, at 45.12 mg / L, 4.95 mg / L, 7.10 NTU, and 25.03. This data is transmitted to the control center in real time, providing data support for subsequent treatment steps. This recycled water was taken from the sewage treatment plant before disinfection, and plate counts revealed 4.33 × 10 4 CFU / mL, sulfonamide resistance gene sul1 was 1.09×10 9 copies / mL, and the total concentration of sulfonamide antibiotics with the highest detection rate was 0.34 μg / L.

[0043] 2) Based on data from the water quality testing unit, the control center calculated the required free chlorine dosage to be 7.50 mg / L. It then sent a signal to activate the metering pump, which rapidly and thoroughly mixed the sodium hypochlorite with the reclaimed water through the pipes. The free chlorine control system detected an effective chlorine concentration of 4.22 mg / L, and the intelligent analysis and control center confirmed that the effective chlorine concentration was within the range of 2 to 15 mg / L. By precisely controlling the chlorine dosage, treatment effectiveness was ensured while preventing environmental contamination from excessive chlorine.

[0044] 3) The chlorinated reclaimed water enters the ceramic membrane aeration + VUV irradiation unit. The average pore size of the ceramic membrane is 1 μm. This unit receives control signals from the intelligent analysis and control center, starts aeration and VUV irradiation, and adjusts the aeration rate to 0.5 mL / min and the vacuum ultraviolet irradiation dose to 600 mJ / cm according to the signals. 2 (Radiation intensity 10mW / cm 2, hydraulic retention time 60s). By increasing the dissolved oxygen content of the water body through a specific aeration volume, the VUV catalysis of free chlorine is strengthened to produce highly active oxidative free radicals, which effectively kill microorganisms in the water, degrade resistance genes, remove residual antibiotics, block the spread of bacterial resistance, and improve the quality of the effluent.

[0045] 4) After disinfection, the reclaimed water enters a post-treatment water quality testing unit for standard water quality indicators. COD, ammonia nitrogen, turbidity, and color were measured at 27.5 mg / L, 0.30 mg / L, 6.57 NTU, and 9.50, respectively. Further water sampling revealed no bacteria or antibiotics, representing a 100% removal rate. The sul1 gene removal rate reached 4.01 log, a 99.99% removal rate. The effluent was then reused.

[0046] The flowchart of the ceramic membrane micro-nano aeration coupled VUV / NaClO reclaimed water disinfection method according to Example 1 of the present invention is shown in FIG. Figure 1 .

[0047] The schematic diagram of the water purification and disinfection reactor used in Example 1 is shown in Figure 2 and Figure 3 .

[0048] Figure 2 and Figure 3 In the figure, 1-upper plate, 2-quartz tube, 3-vacuum ultraviolet lamp, 4-support rod, 5-exhaust pipe, 6-blower, 7-aeration plate, 8-lower plate, 9-reactor shell, 10-flow guide, 11-liquid surface, (1-1)-air inlet, (4-1)-air outlet, (8-1)-opening, (9-1)-water outlet, (10-1)-water inlet.

[0049] The deflector 10 is a hollow tank structure, and its three-dimensional schematic diagram is as shown in FIG. Figure 4 shown.

[0050] The water disinfection and purification reactor consists of an upper plate, a quartz tube, a vacuum ultraviolet lamp, a support rod, an exhaust pipe, a blower, a ceramic membrane aerator, a lower plate, a reactor shell, and a flow guide. The flow guide is sealed to the side wall of the reactor body; the support rod is fixed between the upper plate and the lower plate, the air outlet of the support rod is connected to the blower, and the air outlet of the blower is connected to the ceramic membrane aerator; the vacuum ultraviolet lamp is fixed inside the quartz tube; and the ceramic membrane aerator is arranged below the lower plate. The flow guide is used to guide the direction of water flow, ensure that the water is evenly distributed inside the reactor, and improve the treatment effect; the support rod is used to fix the ultraviolet lamp tube, filtration system and other components to ensure its stability and safety during operation. In order to ensure the quality of the effluent, the reactor is also equipped with a control system for monitoring and controlling the operating parameters of the reactor, such as water inlet flow, disinfection time, aeration volume, etc.

[0051] In a water disinfection and purification reactor, ceramic membrane micro-nano aeration, introduced at the bottom of the VUV irradiation zone, promotes micro-turbulence in the reclaimed water within the disinfection reaction system. This effectively overcomes the challenges of short UV penetration distance and low transmittance in reclaimed water, ensuring that pollutants are fully exposed to VUV light and oxidatively active substances, leading to efficient removal. The water disinfection and purification reactor effectively creates the appropriate hydraulic conditions to fully kill ARGs while avoiding waste of UV supply. Micro-nano bubbles directly destroy bacterial cell structures. More importantly, the tiny bubbles provided by microporous aeration create turbulent micro-environmental conditions, allowing free chlorine and oxygen to react with vacuum UV light to produce highly active ·OH, ClO·, and O3. This not only enhances disinfection effectiveness but also promotes advanced oxidation to remove organic pollutants. It also ensures uniform UV exposure as the water flows vertically, significantly improving UV radiation utilization and avoiding waste of UV supply, thereby saving energy input. Disinfection processes implemented using this water disinfection and purification reactor are stable and energy-efficient.

[0052] Comparative Example 1

[0053] Take the effluent from the sewage treatment plant before disinfection as in the example above and process it as follows:

[0054] 1) Recycled water first enters the water quality automatic detection unit. The online automatic monitoring platform measured COD, ammonia nitrogen, turbidity and color indicators of 45.65 mg / L, 5.23 mg / L, 7.15 NTU, and 25.06 respectively. The culturable bacteria measured by plate count were 4.33×10 4 CFU / mL, sulfonamide resistance gene sul1 was 1.09×10 9 The total concentration of sulfonamide antibiotics with the highest detection rate was 0.34 μg / L. After the data is tested, it is transmitted to the intelligent analysis and control center in real time.

[0055] 2) Based on the detected water quality parameters, the control center sends a signal to the free chlorine dosing unit, adding 7.50 mg / L sodium hypochlorite to the reaction system through the metering pump and pipeline mixing system, so that the sodium hypochlorite and the recycled water are fully mixed and the chlorination reaction occurs fully.

[0056] 3) The free chlorine monitoring unit detects that the effective chlorine concentration after mixing is 4.18 mg / L and transmits the chlorine concentration signal to the control center in real time to ensure that the effective chlorine concentration is within the range of 2 to 15 mg / L.

[0057] 4) After chlorine disinfection, the reclaimed water enters a post-treatment water quality testing unit, where water samples are collected for testing of bacteria, ARGs, and antibiotic levels. The results show a 2.01-log reduction in bacteria, for a 99.02% bacterial removal rate; a 0.15-log reduction in the sul1 gene, for a 29.21% sul1 gene removal rate; and a 51.5% antibiotic degradation rate. The effluent is then reused.

[0058] Comparative Example 2

[0059] Similarly, the effluent from the sewage treatment plant before disinfection in the same embodiment was processed as follows:

[0060] 1) Recycled water first enters the water quality automatic detection unit. The online automatic monitoring platform measured COD, ammonia nitrogen, turbidity and color indicators as 46.32 mg / L, 5.51 mg / L, 7.22 NTU, and 25.12 respectively. The number of culturable bacteria measured by plate count was 4.33×10 4 CFU / mL, sulfonamide resistance gene sul1 was 1.09×10 9 The total concentration of sulfonamide antibiotics with the highest detection rate was 0.34 μg / L. The detected data was fed back to the intelligent analysis and control center in real time through sensors.

[0061] 2) UV irradiation. The control center analyzes the monitoring data and sends a control signal to the UV irradiation unit. The UV irradiation amount is 600mJ / cm 2 (Radiation intensity 10mW / cm 2 , hydraulic retention time 60s). Ultraviolet rays can destroy the DNA or RNA structure of pathogenic microorganisms, making them lose their reproductive ability, thereby achieving the purpose of disinfection.

[0062] 3) After UV disinfection, the reclaimed water enters a post-treatment water quality testing unit for bacteria, ARGs, and antibiotic content. The results indicate a 2.54-log bacterial removal rate (99.71%), a 0.57-log sul1 gene removal rate (73.08%), and a 20.3% antibiotic degradation rate. The effluent is then reused.

[0063] Comparative Example 3

[0064] Similarly, the effluent from the sewage treatment plant before disinfection in the same embodiment was processed as follows:

[0065] 1) Recycled water first enters the water quality automatic detection unit. The online automatic monitoring platform measured COD, ammonia nitrogen, turbidity and color indicators as 45.33 mg / L, 5.12 mg / L, 7.25 NTU, and 24.36 respectively. The number of culturable bacteria measured by plate count was 4.33×10 4 CFU / mL, sulfonamide resistance gene sul1 was 1.09×109 The total concentration of sulfonamide antibiotics with the highest detection rate was 0.34 μg / L. The detected data was fed back to the intelligent analysis and control center in real time through sensors.

[0066] 2) The control center sends a quantitative dosing signal to the free chlorine dosing unit, which then adds 7.5 mg / L of sodium hypochlorite to the sewage through a metering pump. The recycled water is then mixed through the pipeline to allow the recycled water to fully react with the sodium hypochlorite, killing most pathogenic microorganisms in the water. The free chlorine monitoring unit monitors the effective chlorine concentration in real time, and the effective chlorine concentration after mixing is 4.13 mg / L. ， And feed back to the control center to ensure that the effective chlorine concentration is within the range of 2 to 15 mg / L.

[0067] 3) The sewage that has been disinfected with chlorine and has qualified effective chlorine content enters the UV irradiation unit, receives the control signal from the control center, and starts ultraviolet radiation. The ultraviolet radiation amount is 600mJ / cm 2 (Radiation intensity 10mW / cm 2 , hydraulic retention time 60s) to further inactivate residual pathogenic microorganisms.

[0068] 4) After UV / NaClO combined disinfection, the reclaimed water was fed into a post-treatment water quality testing unit for bacteria, ARGs, and antibiotic content. No bacteria were detected, and the sul1 gene was removed by 1.53 logs, resulting in a sul1 gene removal rate of 97.05%, and an antibiotic degradation rate of 72.5%. The effluent was then reused.

[0069] Comparative Example 4

[0070] Similarly, the effluent from the sewage treatment plant before disinfection in Example 1 was treated as follows:

[0071] 1) Recycled water first enters the water quality automatic detection unit. The online automatic monitoring platform measured COD, ammonia nitrogen, turbidity and color indicators as 44.69 mg / L, 5.78 mg / L, 7.02 NTU, and 24.56, respectively. The number of culturable bacteria measured by plate count was 4.33×10 4 CFU / mL, sulfonamide resistance gene sul1 was 1.09×10 9 The total concentration of sulfonamide antibiotics with the highest detection rate was 0.34 μg / L. The detected data was fed back to the intelligent analysis and control center in real time through sensors.

[0072] 2) The control center sends a quantitative dosing signal to the free chlorine dosing unit, which then adds 7.5 mg / L of sodium hypochlorite to the sewage through a metering pump. The recycled water is then mixed through the pipeline to allow the recycled water to fully react with the sodium hypochlorite, killing most pathogenic microorganisms in the water. The free chlorine monitoring unit monitors the effective chlorine concentration in real time, and the effective chlorine concentration after mixing is 4.25 mg / L. ， And feed back to the control center to ensure that the effective chlorine concentration is within the range of 2 to 15 mg / L.

[0073] 3) The sewage that has been disinfected with chlorine and has qualified effective chlorine content enters the VUV irradiation unit, receives the control signal from the control center, and starts ultraviolet radiation. The vacuum ultraviolet irradiation amount is 600mJ / cm 2 (Radiation intensity 10mW / cm 2 , hydraulic retention time 60s) to further inactivate residual pathogenic microorganisms.

[0074] 4) After VUV / NaClO combined disinfection, the reclaimed water was fed into a post-treatment water quality testing unit for bacteria, ARGs, and antibiotic content. No bacteria were detected, and the sul1 gene was removed by 1.98 log, resulting in a sul1 gene removal rate of 98.95%, and an antibiotic degradation rate of 85.4%. The effluent was then reused.

[0075] Comparative Examples 1 to 4 used the same reactor as Example 1, with the difference being the switches of some units. The ultraviolet lamp used in Comparative Example 3 was a UV254 lamp.

[0076] Figure 5 It is the bacteria removal rate of the scheme of Example 1 and Comparative Examples 1-4.

[0077] Figure 6 It is the antibiotic degradation rate of the scheme of Example 1 and Comparative Examples 1-4.

[0078] Figure 7 It is the sul1 gene removal rate of the scheme of Example 1 and Comparative Examples 1-4.

[0079] Figures 5 to 7 In the figure, abscissas A to E represent the results of Example 1 and Comparative Examples 1 to 4, respectively.

[0080] By comparison Figures 5 to 7 It can be found that Example 1 can significantly improve the removal rate of sul1 gene and antibiotics, completely inactivate bacteria, and the effect is significantly better than the other four comparative examples.

[0081] Compared with chlorine disinfection alone (Comparative Example 1), UV disinfection alone (Comparative Example 2) improved the bacteria removal rate and sul1 gene removal rate, but the antibiotic degradation rate was not as good as chlorine disinfection alone.

[0082] Compared with chlorine disinfection alone and UV disinfection alone (Comparative Examples 1 and 2), the combined UV / chlorine disinfection (Comparative Example 3) can greatly improve the quality of discharged wastewater, and the bacterial removal rate, antibiotic degradation rate, and sul1 gene removal rate are all improved.

[0083] The shorter the wavelength of the ultraviolet lamp, the better the disinfection effect. According to the comparison of the treatment of VUV / NaClO disinfection (Comparative Example 4) and UV / NaClO disinfection (Comparative Example 3), VUV / NaClO can not only completely inactivate bacteria, but also improve the antibiotic degradation rate and sul1 gene removal rate.

[0084] During treatment, increasing aeration (Example 1) can also optimize the disinfection effect. Compared with Example 4, Example 1 adds ceramic membrane micro-nano aeration, which significantly improves the degradation rate of antibiotics in the effluent and further ensures the water quality safety of the recycled water.

[0085] In summary, the coupling scheme of ceramic membrane micro-nano aeration technology and VUV / NaClO advanced oxidation process provided by the present invention can effectively remove antibiotic-resistant pollutants in reclaimed water, breaking through the limitations of existing technologies, significantly improving disinfection and sterilization efficiency, while reducing the biological toxicity of water bodies and lowering ecological safety risks, thereby more comprehensively ensuring the safety and reliability of water quality.

[0086] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A disinfection method for simultaneously removing antibiotics, drug-resistant bacteria and resistance genes in water and reducing disinfection by-products, characterized in that: The following steps are involved: Sodium hypochlorite is added to the water to be disinfected to ensure that the concentration of available chlorine in the water to be disinfected is 2 to 15 mg / L; DO is further introduced through aeration and VUV disinfection is performed to simultaneously remove antibiotics, drug-resistant bacteria and resistance genes in the water to be disinfected and reduce disinfection by-products; The aeration rate of the aeration is 0.3-1 mL / min; The VUV irradiation dose is 300-1000 mJ / cm 2 ; Before adding sodium hypochlorite, test the COD and ammonia nitrogen of the water to be disinfected. When the COD in the water to be disinfected is ≤50mg / L and the ammonia nitrogen is ≤8mg / L, the chlorine dosage is 5-15mg / L; when 50<COD≤60mg / L and 5<ammonia nitrogen≤15mg / L, the chlorine dosage is 8-20mg / L.

2. The disinfection method for simultaneously removing antibiotics, drug-resistant bacteria and resistance genes in water and reducing disinfection by-products according to claim 1, characterized in that: The aeration is achieved through a microporous aeration membrane with a diameter of 0.1 to 5 μm.

3. The disinfection method for simultaneously removing antibiotics, drug-resistant bacteria and resistance genes in water and reducing disinfection by-products according to claim 2, characterized in that: The material of the microporous aeration membrane is ceramic.

4. Use of the disinfection method for simultaneously removing antibiotics, drug-resistant bacteria and resistance genes in water and reducing disinfection by-products according to any one of claims 1 to 3 in sewage treatment.

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