A method for treating antibiotic pollution in water bodies of a river basin

Abstract

The present invention relates to the technical field of sewage treatment, and specifically relates to a method for treating antibiotic pollution in basin water bodies, comprising the following steps: S1. Applying an oxidant to the extracted basin water body and applying a direct current electric field to obtain a once-treated water body; S2. Applying activated microspheres and performing ultraviolet light irradiation treatment to obtain reclaimed water; S3. Reclaiming the reclaimed water into the basin water body in intervals and applying activated microspheres with corresponding diameters and masses to the reclaimed water in each interval; The treatment method of the present invention first realizes the directional oxidation of antibiotic molecules through the coupling effect of the direct current electric field and the oxidant. After the reaction is completed, the pH is adjusted to promote the coprecipitation of antibiotic degradation products and metal ions, and colloidal pollutants are removed synchronously; Then, activated microspheres and ultraviolet light irradiation treatment are applied to realize the mineralization of antibiotics. When recharging, it is recharged in intervals to enhance the treatment effect of antibiotics in the basin water body.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage treatment, and specifically relates to a method for treating antibiotic pollution in river basin water bodies. Background Art

[0002] The sources of antibiotics in the environment mainly include domestic sewage, medical wastewater, and the discharge of animal feed and aquaculture wastewater. Antibiotic residues in the environment can re-enter the human body through various ways. The most important ones are drinking water containing antibiotics, eating meat and vegetables with antibiotic residues, and it can also return to the human body through the ecological cycle.

[0003] In the prior art, there are the following problems with the methods for treating antibiotic pollution in river basin water bodies: First, the distribution of antibiotics in different water depths and media (water bodies, sediments) varies greatly, and single treatment is difficult to cover comprehensively; Second, the adsorption capacity of traditional adsorbents (such as activated carbon) for antibiotics is limited, and the regeneration cost is high. Therefore, the present invention decides to design a method for treating antibiotic pollution in river basin water bodies. Summary of the Invention

[0004] To solve the above problems, the present invention provides a method for treating antibiotic pollution in river basin water bodies.

[0005] A method for treating antibiotic pollution in river basin water bodies includes the following steps:

[0006] S1. Apply an oxidant to the extracted river basin water body. The application concentration of the oxidant is 0.1 - 0.3% of the total antibiotic concentration in the extracted river basin water body, and apply a DC electric field. The current of the DC electric field is 40 - 70 mA, the potential gradient is 0.4 - 0.6 V / cm, the reaction time is 60 - 80 min. After the reaction is completed, adjust the pH to 6 - 8 with a pH regulator, and obtain the water body after primary treatment through solid-liquid separation;

[0007] S2. Then apply 0.3 - 0.8 g / L of activated microsphere C to the water body after primary treatment obtained in step S1, and perform ultraviolet light irradiation treatment. The ultraviolet light intensity is 50 - 90 μw / cm 2 , the time is 30 - 50 min, and then perform membrane separation to obtain reclaimed water;

[0008] S3. Recharge the reclaimed water obtained in step S2 into the river basin water body at a recharge frequency of 1 - 3 times / 1 week. The single recharge method is as follows:

[0009] S3-1. Divide the basin water body into a first interval, a second interval, and a third interval according to depth. The first interval is between 1 / 4 and 3 / 4 of the basin water body depth, the second interval is between 1 / 4 of the basin water body depth and the water surface of the basin water body, and the third interval is between 3 / 4 of the basin water body depth and the bottom of the basin water body;

[0010] S3-2. Divide the reclaimed water into first reclaimed water, second reclaimed water, and third reclaimed water. The volume ratio of the first reclaimed water, second reclaimed water, and third reclaimed water is 4 - 7:3:2;

[0011] S3-3. Apply activated microspheres A accounting for 1 - 2‰ of its mass to the first reclaimed water and then recharge it into the first interval;

[0012] Apply activated microspheres B accounting for 2 - 5‰ of its mass to the second reclaimed water and then recharge it into the second interval;

[0013] Apply activated microspheres C accounting for 5 - 10‰ of its mass to the third reclaimed water and then recharge it into the third interval;

[0014] Wherein, the single recharge volume of the reclaimed water is denoted as V, with the unit of m 3 , the average flow velocity of the basin water body is denoted as v, with the unit of m / h, and the depth of the basin water body is denoted as h, with the unit of m;

[0015] The relationship among the single recharge volume of the reclaimed water, the average flow velocity of the basin water body, and the depth of the basin water body is: V = hv 2 .

[0016] Furthermore, the preparation methods of the activated microspheres A, activated microspheres B, and activated microspheres C are as follows:

[0017] After grinding dickite, place it in a nitrogen atmosphere, heat it at a rate of 10 - 15 °C / min to 450 - 550 °C, and keep it warm for 1.5 - 2.5 h, and then grind it to obtain dickite microspheres with a particle size of 0.1 - 1.0 mm;

[0018] Mix the algal solution and lanthanum chloride solution with a mass fraction of 60 - 70% according to a mass ratio of 1:200 - 300 to obtain a mixed solution, and immerse the dickite microspheres in the mixed solution at a temperature of 35 - 55 °C for 30 - 40 min to obtain loaded microspheres. Divide the loaded microspheres into loaded microspheres A with a particle size < 0.3 mm, loaded microspheres B with a particle size of 0.3 - 0.5 mm, and loaded microspheres C with a particle size > 0.5 mm;

[0019] Immerse the loaded microspheres A in an ethanol solution containing 1 - 3 wt% of silane, ultrasonically disperse for 20 - 30 min, and dry and cure at 65 - 70 °C for 1.5 - 2 h to obtain activated microspheres A;

[0020] Under nitrogen protection, the loaded microspheres B are placed in hexamethyldisilazane vapor and reacted at 75 - 80 °C for 55 - 65 min to obtain activated microspheres B;

[0021] The loaded microspheres C are first frozen at -60 to -50 °C for 7 - 8 h, thawed at room temperature for 3 - 4 h, then frozen at -40 to -20 °C for 8 - 10 h, thawed at room temperature for 3 - 4 h, and finally frozen at -5 to 0 °C for 7 - 8 h and thawed to room temperature to obtain activated microspheres C.

[0022] Note: After high-temperature calcination, dickite forms a porous structure, captures antibiotic molecules through physical adsorption and ion exchange. Lanthanum chloride can form La³⁺ active sites on the surface of the microspheres, catalyze H2O to generate hydroxyl radicals through the Fenton-like reaction, degrade the adsorbed antibiotics. The loaded bacteria and algae secrete hydrolases to specifically cleave the antibiotic molecular bonds and convert the antibiotics into low-toxic metabolites; under multiple cycles of freezing and thawing, through the ice crystal extrusion effect, through-hole channels (pore diameter 50 - 200 nm) are formed inside the microspheres to improve the mass transfer efficiency, increase the diffusion rate of antibiotics, and during this process, the bacteria and algae cells form stress-resistant spores or biofilms after repeated freezing and thawing and remain active in the watershed water body.

[0023] Furthermore, the preparation method of the bacteria-algae solution is as follows:

[0024] Chlorella vulgaris and Phormidium sp. are mixed to prepare an algal solution, with the content of Chlorella vulgaris being 10 8 ~10 9 cells / mL and the content of Phormidium sp. being 10 5 ~10 6 cells / mL;

[0025] Bacillus subtilis and Bacillus velezensis are mixed to prepare a bacterial solution, with the content of Bacillus subtilis being 10 8 ~10 9 cfu / mL and the content of Bacillus velezensis being 10 7 ~10 8 cfu / mL;

[0026] The algal solution and the bacterial solution are mixed evenly at a mass ratio of 1:0.3 - 0.5 to obtain the bacteria-algae solution.

[0027] Note: The cellulose of Chlorella vulgaris and ammonium alginate of Phormidium sp. provide abundant negative charge sites for the activated microspheres to adsorb antibiotics through electrostatic interaction; Bacillus subtilis can stably degrade pollutants in the range of pH 2.5 - 8, Bacillus velezensis is resistant to high temperature and high salt environments, and Bacillus velezensis inhibits the formation of pathogenic biofilms through quorum sensing and reduces the spread of antibiotic resistance genes.

[0028] Further, in step S1, the oxidant is ferrate or persulfate.

[0029] Note: Ferrate has strong anti-environmental interference, and persulfate preferentially attacks the piperazine ring, resulting in the cleavage of C-N / C-F bonds; mineralization is achieved through the electron transfer of aniline N and the cleavage of sulfonamide bonds. Both are good oxidants.

[0030] Further, in step S1, the pH regulator is a sodium hydroxide solution with a mass fraction of 8-12%.

[0031] Note: Sodium hydroxide can make the wastewater clearer and more transparent. In addition, sodium hydroxide can also reduce the hardness of the water and remove dirt and impurities in the water.

[0032] Further, in step S2, the membrane used for membrane separation is a cellulose acetate reverse osmosis membrane or a polyamide nanofiltration membrane.

[0033] Note: Both the cellulose acetate reverse osmosis membrane and the polyamide nanofiltration membrane can effectively retain antibiotic pollutants.

[0034] Further, the antibiotic includes at least one of tetracycline, ciprofloxacin, and sulfamethoxazole.

[0035] Note: The method of the present invention can effectively treat the above-mentioned antibiotic pollutants.

[0036] Compared with the existing methods for treating antibiotic pollution, the beneficial effects of the present invention are as follows:

[0037] (1) In the treatment method of the present invention, firstly, through the coupling action of a direct current electric field and an oxidant, the directional oxidation of antibiotic molecules is achieved. After the reaction is completed, the pH is adjusted to promote the coprecipitation of antibiotic degradation products and metal ions, and colloidal pollutants are removed synchronously; then, activated microsphere C and ultraviolet light irradiation treatment are applied. Activated microsphere C uses a porous material as a carrier and is loaded with a catalyst. Under the excitation of ultraviolet light, photogenerated holes and electrons are generated to achieve the mineralization of antibiotics. Then, membrane separation is used to selectively retain residual antibiotics, and the reclaimed water meets the reclamation standard and is recharged in different intervals. In the first interval, small-sized activated microsphere A is applied, with a long suspension time, enhancing the photocatalytic degradation of dissolved antibiotics; in the third interval, large-sized activated microsphere C is applied, quickly settling to cover the bottom mud, inhibiting the re-release of heavy metals and antibiotics; the application amount of activated microsphere C in the third interval is significantly higher than that in the first interval, matching the vertical distribution law of pollutants and targeting to reduce the risk of benthic organism enrichment.

[0038] (2) The present invention applies activated microspheres A, activated microspheres B, and activated microspheres C to the water body of the basin. The functions of each component are as follows: After kaolin is calcined at high temperature, a porous structure is formed, and antibiotic molecules are captured through physical adsorption and ion exchange. Lanthanum chloride can form La³⁺ active sites on the surface of kaolin microspheres, and hydroxyl radicals are generated by catalyzing H2O through the Fenton-like reaction to degrade the adsorbed antibiotics. The loaded bacteria and algae secrete hydrolases to specifically cut the antibiotic molecular bonds and convert the antibiotics into low-toxic metabolites; a hydrophobic layer is formed on the surface of activated microsphere A, enabling activated microsphere A to attach to bubbles and increase buoyancy; a dense layer is formed on the surface of activated microsphere B to seal the pores, prevent water from entering, and maintain the internal air, thereby reducing the density; under multiple cycles of freezing and thawing, activated microsphere C forms through-hole channels inside by the ice crystal extrusion effect, improving the mass transfer efficiency and increasing the diffusion rate of antibiotics. During this process, the bacteria and algae cells form stress-resistant spores or biofilms after repeated freezing and thawing and remain active in the water body of the basin.

[0039] (3) By recharging the treated reclaimed water into the water body of the basin, compared with directly adding uncontaminated purified water, the ecological system balance in the original water body of the basin may be damaged due to the water quality differences (such as salinity, temperature) between the purified water and the water body of the basin. However, the recharge of reclaimed water can gradually repair the habitat and avoid sudden environmental disturbances; moreover, the residual oxidant in the reclaimed water can react catalytically with the activated microspheres to generate free radicals, reducing the additional chemical dosage. Recharging in intervals can, on the one hand, promote the uniform diffusion of dissolved oxygen in the water body of the basin, and on the other hand, prevent the activated microspheres from taking effect first at the same recharge height and weakening their effects in other intervals. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a comparison chart of the results of Exploration 1 in the experimental examples of the present invention;

[0041] Figure 2 It is a comparison chart of the results of Exploration 2 in the experimental examples of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0042] To further elaborate on the methods and achieved effects adopted by the present invention, the technical solutions of the present invention will be clearly and completely described below in combination with experiments.

[0043] Example 1: A method for treating antibiotic pollution in the water body of a basin, comprising the following steps:

[0044] S1. Apply an oxidant to the extracted basin water body. The oxidant is ferrate (such as potassium ferrate), and the application concentration of the oxidant is 0.2% of the total antibiotic concentration in the extracted basin water body. Apply a direct current electric field with a current of 55 mA and a potential gradient of 0.5 V / cm. The reaction time is 70 min. After the reaction is completed, adjust the pH to 7 with a pH regulator. The pH regulator is a 10% sodium hydroxide solution by mass fraction. After solid-liquid separation, obtain the water body treated once.

[0045] S2. Then apply 0.6 g / L of activated microsphere C to the water body treated once obtained in step S1, and perform ultraviolet light irradiation treatment. The ultraviolet light intensity is 70 μw / cm 2 , and the time is 40 min. Then select a cellulose acetate reverse osmosis membrane for membrane separation to obtain reclaimed water.

[0046] The preparation methods of activated microsphere A, activated microsphere B, and activated microsphere C are as follows:

[0047] After grinding dickite, place it in a nitrogen atmosphere and heat it to 500 °C at a rate of 12 °C / min and hold for 2 h, and then grind it to obtain dickite microspheres with a particle size of 0.2 - 0.8 mm.

[0048] Mix the algal-bacterial solution and a 65% lanthanum chloride solution by mass ratio of 1:250 to obtain a mixed solution, and immerse the dickite microspheres in the mixed solution at a temperature of 42 °C for 35 min to obtain loaded microspheres. Divide the loaded microspheres into loaded microsphere A with a particle size < 0.3 mm, loaded microsphere B with a particle size of 0.3 - 0.5 mm, and loaded microsphere C with a particle size > 0.5 mm.

[0049] The preparation method of the algal-bacterial solution is as follows:

[0050] Mix chlorella and phormidium to make an algal solution with a chlorella content of 10 8 cells / mL and a phormidium content of 10 5 cells / mL;

[0051] Mix bacillus subtilis and bacillus velezensis to make a bacterial solution with a bacillus subtilis content of 10 8 cfu / mL and a bacillus velezensis content of 10 7 cfu / mL;

[0052] Mix the algal solution and the bacterial solution evenly by a mass ratio of 1:0.4 to obtain the algal-bacterial solution;

[0053] Immerse loaded microsphere A in an ethanol solution containing 2 wt% silane, ultrasonically disperse it for 25 min with an ultrasonic power of 50 KHz, and dry and cure it at 68 °C for 1.8 h to obtain activated microsphere A;

[0054] Under nitrogen protection, the loaded microspheres B were placed in the vapor of hexamethyldisilazane and reacted at 78 °C for 60 min to obtain activated microspheres B;

[0055] The loaded microspheres C were first frozen at -55 °C for 7.5 h, thawed at room temperature for 3.5 h, then frozen at -30 °C for 9 h, thawed at room temperature for 3.5 h, and finally frozen at -2 °C for 7.5 h and thawed to room temperature of 25 °C to obtain activated microspheres C;

[0056] S3. The reclaimed water obtained in step S2 was recharged into the basin water body at a recharge frequency of 2 times / 1 week. The single recharge method was as follows:

[0057] S3-1. The basin water body was divided into a first interval, a second interval, and a third interval according to depth. The first interval was between 1 / 4 and 3 / 4 of the depth of the basin water body, the second interval was between 1 / 4 of the depth of the basin water body and the water surface, and the third interval was between 3 / 4 of the depth of the basin water body and the bottom of the basin water body;

[0058] S3-2. The reclaimed water was divided into first reclaimed water, second reclaimed water, and third reclaimed water. The volume ratio of the first reclaimed water, the second reclaimed water, and the third reclaimed water was 5.5:3:2;

[0059] S3-3. After adding activated microspheres A accounting for 1.5‰ of its mass to the first reclaimed water, it was recharged into the first interval;

[0060] After adding activated microspheres B accounting for 3.5‰ of its mass to the second reclaimed water, it was recharged into the second interval;

[0061] After adding activated microspheres C accounting for 7.5‰ of its mass to the third reclaimed water, it was recharged into the third interval;

[0062] Among them, the single recharge volume of the reclaimed water was denoted as V, with the unit of m 3 , the average flow velocity of the basin water body was denoted as v, with the unit of m / h, and the depth of the basin water body was denoted as h, with the unit of m;

[0063] The relationship among the single recharge volume of the reclaimed water, the average flow velocity of the basin water body, and the depth of the basin water body was: V = hv 2 .

[0064] Example 2: The difference between this example and Example 1 was that in step S1, the oxidant was potassium persulfate, the application concentration of the oxidant was 0.1% of the total antibiotic concentration in the extracted basin water body, and a DC electric field was applied. The current of the DC electric field was 40 mA, the potential gradient was 0.4 V / cm, and the reaction time was 60 min.

[0065] Example 3: The difference between this example and Example 1 is that in step S1, the oxidant is potassium ferrate, the application concentration of the oxidant is 0.3% of the total antibiotic concentration in the extracted river water body, and a DC electric field is applied. The current of the DC electric field is 70 mA, the potential gradient is 0.6 V / cm, and the reaction time is 80 min.

[0066] Example 4: The difference between this example and Example 1 is that in step S1, after the reaction is completed, the pH is adjusted to 6 with a pH regulator, and the pH regulator is a sodium hydroxide solution with a mass fraction of 8%.

[0067] Example 5: The difference between this example and Example 1 is that in step S1, after the reaction is completed, the pH is adjusted to 8 with a pH regulator, and the regulator is a sodium hydroxide solution with a mass fraction of 12%.

[0068] Example 6: The difference between this example and Example 1 is that in step S2, 0.3 g / L of activated microsphere C is applied to the water body treated once obtained in step S1, and ultraviolet light irradiation treatment is carried out. The ultraviolet light intensity is 50 μw / cm 2 , the time is 30 min, and then a polyamide nanofiltration membrane is selected for membrane separation to obtain reclaimed water.

[0069] Example 7: The difference between this example and Example 1 is that in step S2, 0.8 g / L of activated microsphere C is applied to the water body treated once obtained in step S1, and ultraviolet light irradiation treatment is carried out. The ultraviolet light intensity is 90 μw / cm 2 , the time is 50 min, and then a cellulose acetate reverse osmosis membrane is selected for membrane separation to obtain reclaimed water.

[0070] Example 8: The difference between this example and Example 1 is that in step S3-2, the reclaimed water is divided into the first reclaimed water, the second reclaimed water, and the third reclaimed water. The volume ratio of the first reclaimed water, the second reclaimed water, and the third reclaimed water is 4:3:2. 1‰ of the mass of the activated microspheres is applied to the first reclaimed water and then recharged into the first interval; 2‰ of the mass of the activated microspheres is applied to the second reclaimed water and then recharged into the second interval; 5‰ of the mass of the activated microspheres is applied to the third reclaimed water and then recharged into the third interval.

[0071] Example 9: The difference between this example and Example 1 is that in step S3-2, the reclaimed water is divided into the first reclaimed water, the second reclaimed water, and the third reclaimed water. The volume ratio of the first reclaimed water, the second reclaimed water, and the third reclaimed water is 7:3:2. 2‰ of the mass of the activated microspheres is applied to the first reclaimed water and then recharged into the first interval; 5‰ of the mass of the activated microspheres is applied to the second reclaimed water and then recharged into the second interval; 10‰ of the mass of the activated microspheres is applied to the third reclaimed water and then recharged into the third interval.

[0072] Example 10: The difference between this example and Example 1 is that in step S3, the reclaimed water obtained in step S2 is recharged into the basin water body at a recharge frequency of once a week.

[0073] Example 11: The difference between this example and Example 1 is that in step S3, the reclaimed water obtained in step S2 is recharged into the basin water body at a recharge frequency of three times a week.

[0074] Example 12: The difference between this example and Example 1 is that after dickite is crushed, it is placed in a nitrogen atmosphere and heated to 450 °C at a rate of 10 °C / min and held for 1.5 h, and then ground to obtain dickite microspheres with a particle size of 0.2 - 0.7 mm.

[0075] Example 13: The difference between this example and Example 1 is that after dickite is crushed, it is placed in a nitrogen atmosphere and heated to 550 °C at a rate of 15 °C / min and held for 2.5 h, and then ground to obtain dickite microspheres with a particle size of 0.1 - 1.0 mm.

[0076] Example 14: The difference between this example and Example 1 is that the algal solution and a lanthanum chloride solution with a mass fraction of 60% are mixed at a mass ratio of 1:200 to obtain a mixed solution, and the dickite microspheres are immersed in the mixed solution at a temperature of 35 °C for 30 min.

[0077] Example 15: The difference between this example and Example 1 is that the algal solution and a lanthanum chloride solution with a mass fraction of 70% are mixed at a mass ratio of 1:300 to obtain a mixed solution, and the dickite microspheres are immersed in the mixed solution at a temperature of 55 °C for 40 min.

[0078] Example 16: The difference between this example and Example 1 is that the loaded microspheres A are immersed in an ethanol solution containing 1 wt% silane, ultrasonically dispersed for 20 min, and dried and cured at 65 °C for 1.5 h to obtain activated microspheres A.

[0079] Example 17: The difference between this example and Example 1 is that the loaded microspheres A are immersed in an ethanol solution containing 3 wt% silane, ultrasonically dispersed for 30 min, and dried and cured at 70 °C for 2 h to obtain activated microspheres A.

[0080] Example 18: The difference between this example and Example 1 is that under nitrogen protection, the loaded microspheres B are placed in hexamethyldisilazane vapor and reacted at 75 °C for 55 min to obtain activated microspheres B.

[0081] Example 19: The difference between this example and Example 1 is that under nitrogen protection, the loaded microspheres B are placed in hexamethyldisilazane vapor and reacted at 80 °C for 65 min to obtain activated microspheres B.

[0082] Example 20: The difference between this example and Example 1 is that the loaded microspheres C are first frozen at -60 °C for 7 h, thawed at room temperature for 3 h, then frozen at -20 °C for 8 h, thawed at room temperature for 3 h, and finally frozen at 0 °C for 7 h and thawed to room temperature of 25 °C to obtain activated microspheres C.

[0083] Example 21: The difference between this example and Example 1 is that the loaded microspheres C are first frozen at -50 °C for 8 h, thawed at room temperature for 4 h, then frozen at -40 °C for 10 h, thawed at room temperature for 4 h, and finally frozen at -5 °C for 8 h and thawed to room temperature of 25 °C to obtain activated microspheres C.

[0084] Example 22: The difference between this example and Example 1 is that the content of Chlorella is 10 8 cells / mL, the content of Phormidium is 10 6 cells / mL, the content of Bacillus subtilis is 10 8 cfu / mL, and the content of Bacillus velezensis is 10 8 cfu / mL. The algal liquid and the bacterial liquid are mixed evenly at a mass ratio of 1:0.3.

[0085] Example 23: The difference between this example and Example 1 is that the content of Chlorella is 10 9 cells / mL, the content of Phormidium is 10 5 cells / mL, the content of Bacillus subtilis is 10 9 cfu / mL, and the content of Bacillus velezensis is 10 7 cfu / mL. The algal liquid and the bacterial liquid are mixed evenly at a mass ratio of 1:0.5.

[0086] Experimental example: The description basis of this experimental example is the recording schemes in Examples 1 to 23, aiming to clarify the actual application effects of the present invention.

[0087] 1) Continuously introduce the watershed water body into the container to maintain 10 m 3 of the flowing watershed water body in the container. Extract 2.25 m 3 of the watershed water body in the container as the watershed water body extracted in step S1 of the method of the present invention for treatment, and then recharge the obtained reclaimed water into the container. 5 h after one recharge is completed, detect the total concentration of antibiotics in the recharged watershed water body to obtain the experimental data regarding Example 10;

[0088] 2) Repeat the operation in 1) two more times. After 5 hours of the two-time recharging, detect the total concentration of antibiotics in the water body of the recharged basin to obtain the experimental data for Example 1;

[0089] 3) Repeat the operation in 1) three more times. After 5 hours of the three-time recharging, detect the total concentration of antibiotics in the water body of the recharged basin to obtain the experimental data for Example 11;

[0090] Taking Example 1 as a benchmark, make corresponding parameter adjustments for the remaining examples, so as to obtain the experimental results of each example. Compare the experimental data of Examples 1 to 23 with the total concentration of antibiotics in the 10m 3 water body of the basin that has not been treated by the method of the present invention to obtain the reduction rate of the antibiotic concentration. The specific exploration results are as follows:

[0091] Explore the effects of the parameters in Exploration 1, Step S1, Step S2, and Step S3 on the antibiotic removal rate and the reduction rate of the antibiotic concentration.

[0092] The difference between Comparative Example 1 and Example 1 is that in Step S3, the applied masses of the activated microspheres A, B, and C in the first interval, the second interval, and the third interval are the same;

[0093] The difference between Comparative Example 2 and Example 1 is that in Step S3, the applied volumes of the first recharged water, the second recharged water, and the third recharged water are the same;

[0094] It can be seen from Figure 1 the results that Comparative Example 1 lacks the difference in the applied masses of the activated microspheres A, B, and C in the first interval, the second interval, and the third interval, and Comparative Example 2 lacks the difference in the applied volumes of the recharged water in the first interval, the second interval, and the third interval. Compared with the reduction rate of the antibiotic concentration in the water body of the basin in Examples 1 to 11, it has decreased significantly. Therefore, it is necessary to perform recharging with different volumes for the depth of the water body of the basin;

[0095] Comparing Examples 1 to 11, it can be seen that if the parameters of the cooperation between the oxidant and the DC electric field are too small or too large, the pH adjustment parameters are too small or too large, the parameters of the cooperation between the activated microsphere C and the ultraviolet light treatment are too small, the applied masses of the activated microspheres A, B, and C in the first interval, the second interval, and the third interval are too small or too large, and the recharging frequency of the recharged water is too small or too large, all of which will reduce the reduction rate of the antibiotic concentration in the water body of the basin. The parameter effect of Example 7 is slightly better than that of Example 1, but the parameters required for the cooperation between the activated microsphere C and the ultraviolet light treatment in Example 7 are relatively large, and the increase amplitude of the parameters is smaller than the increase amplitude of the reduction rate of the antibiotic concentration. Therefore, from the perspective of economy, the parameter effect of Example 1 is relatively better.

[0096] Investigation 2: Investigate the effects of the preparation parameters of activated microspheres A, B, and C on the reduction rate of antibiotic concentration.

[0097] The difference between Comparative Example 3 and Example 1 is that in step S3, activated microspheres A, B, and C are not applied during reinjection;

[0098] From Figure 2 The results show that Comparative Example 3 lacks activated microspheres A, B, and C, which reduces the effect of in-situ purification of antibiotics in the watershed water body compared to Example 1. Therefore, compared to Example 1, the reduction rate of antibiotic concentration in the watershed water body in Examples 12 to 23 decreases significantly;

[0099] Comparing Examples 1, 12 to 23, it can be seen that too small or too large preparation parameters of dickite microspheres, too small or too large preparation parameters of loaded microspheres, too small or too large preparation parameters of activated microsphere A, too small or too large preparation parameters of activated microsphere B, too small or too large preparation parameters of activated microsphere C, and too small or too large proportion of algal solution will all reduce the reduction rate of antibiotic concentration in the watershed water body. Therefore, comprehensively comparing, the parameter effect of Example 1 is relatively better.

Claims

1. A method for treating antibiotic pollution in a water body of a river basin, characterized in that: The following steps are involved: S1. Apply an oxidant to the extracted water body of the river basin, the concentration of the oxidant applied is 0.1-0.3% of the total concentration of antibiotics in the extracted water body of the river basin, and apply a direct current electric field, the current of the direct current electric field is 40-70 mA, the potential gradient is 0.4-0.6 V / cm, the reaction time is 60-80 min, and after the reaction is completed, the pH is adjusted to 6-8 with a pH regulator, and the water body treated once is obtained after solid-liquid separation; S2, adding 0.3-0.8 g / L of activated microspheres C to the treated water obtained in step S1, and irradiating the water with ultraviolet light at an intensity of 50-90 μw / cm 2 , the time is 30~50min, and then membrane separation is performed to obtain reinjection water; S3, the recharge water obtained in step S2 is recharged into the water body of the basin at a recharge frequency of 1 to 3 times per week. The single recharge method is as follows: S3-1. Divide the water body of the basin into the first, second and third intervals according to depth. The first interval is between 1 / 4 and 3 / 4 of the depth of the water body of the basin, the second interval is between 1 / 4 of the depth of the water body of the basin and the surface of the water body of the basin, and the third interval is between 3 / 4 of the depth of the water body of the basin and the bottom of the water body of the basin; S3-2, dividing the recharge water into first recharge water, second recharge water and third recharge water, wherein the volume ratio of the first recharge water, the second recharge water and the third recharge water is 4-7:3:2; S3-3, adding activated microspheres A accounting for 1-2‰ of the mass of the first recharged water and recharging it to the first interval; Adding activated microspheres B accounting for 2-5‰ of the mass of the second recharged water and then recharging it to the second interval; Adding activated microspheres C accounting for 5-10‰ of the mass of the third recharge water and then recharging it to the third interval; The single recharge volume of the recharge water is recorded as V, in m 3 , the average velocity of the water body in the basin is recorded as v, in m / h, and the depth of the water body in the basin is recorded as h, in m; The relationship between the single recharge volume of the recharge water, the average flow velocity of the water body in the basin, and the depth of the water body in the basin is: V=hv 2 ; The preparation methods of the activated microspheres A, B and C are as follows: After the dickite is crushed, it is placed in a nitrogen atmosphere, heated to 450-550°C at a rate of 10-15°C / min, and kept warm for 1.5-2.5 hours, and then ground to obtain dickite microspheres with a particle size of 0.1-1.0 mm; The bacteria and algae solution and the lanthanum chloride solution with a mass fraction of 60-70% are mixed at a mass ratio of 1:200-300 to obtain a mixed solution, and the dickite microspheres are immersed in the mixed solution at a temperature of 35-55° C. for 30-40 minutes to obtain loaded microspheres, and the loaded microspheres are divided into loaded microspheres A with a particle size of less than 0.3 mm, loaded microspheres B with a particle size of 0.3-0.5 mm, and loaded microspheres C with a particle size of more than 0.5 mm; The loaded microspheres A were immersed in an ethanol solution containing 1-3 wt% silane, ultrasonically dispersed for 20-30 min, and dried and cured at 65-70 °C for 1.5-2 h to obtain activated microspheres A; The loaded microspheres B were placed in hexamethyldisilazane vapor under nitrogen protection and reacted at 75-80°C for 55-65 minutes to obtain activated microspheres B; The loaded microspheres C were first frozen at -60~-50℃ for 7~8h, thawed at room temperature for 3~4h, then frozen at -40~-20℃ for 8~10h, thawed at room temperature for 3~4h, and finally frozen at -5~0℃ for 7~8h, thawed to room temperature to obtain activated microspheres C.

2. The method for treating antibiotic pollution in a water body of a river basin as claimed in claim 1, characterized in that: The preparation method of the bacteria and algae solution is: Chlorella and phytoplankton are mixed to make algae liquid, with the content of Chlorella being 10 8 ~10 9 / mL, the content of phytoplankton is 10 5 ~10 6 Pieces / mL; Bacillus subtilis and Bacillus velez are mixed to prepare a bacterial solution, wherein the content of Bacillus subtilis is 10 8 ~10 9 cfu / mL, the content of Bacillus Velez is 10 7 ~10 8 cfu / mL; The algae solution and the bacterial solution were uniformly mixed in a mass ratio of 1:0.3-0.5 to obtain a bacterial-algae solution.

3. The method for treating antibiotic pollution in a water body of a river basin as claimed in claim 1, characterized in that: In step S1, the oxidant is ferrate or persulfate.

4. The method for treating antibiotic pollution in a water body of a river basin as claimed in claim 1, characterized in that: In step S1, the pH adjuster is a sodium hydroxide solution with a mass fraction of 8-12%.

5. The method for treating antibiotic pollution in a water body of a river basin as claimed in claim 1, characterized in that: In step S2, the membrane used for membrane separation is a cellulose acetate reverse osmosis membrane or a polyamide nanofiltration membrane.

6. The method for treating antibiotic pollution in a water body of a river basin as claimed in claim 1, characterized in that: The antibiotics include at least one of tetracycline, ciprofloxacin and sulfamethoxazole.

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