A highly efficient method for acclimating flocculent sludge to remove sulfonamide antibiotics.

Abstract

The application discloses a method for efficiently removing sulfonamide antibiotics by flocculent sludge domestication, and belongs to the technical field of sewage treatment. The method greatly improves the removal rate of sulfonamide antibiotics by adjusting the culture conditions of activated sludge in a traditional activated sludge system. The method can effectively remove antibiotics, has the characteristics of simple operation, low treatment cost and large-scale operation, and the removal of pollutants is mainly realized by sludge adsorption and microbial degradation. The important functional bacteria, nitrifying bacteria, in the activated sludge treatment process can improve the removal efficiency of antibiotics including antibiotic drugs through co-metabolism while completing nitrification, so that the functional bacteria can be enriched by inoculating activated sludge and domesticating the sludge into flocculent form, and the functional bacteria are used to efficiently remove sulfonamide antibiotics.

Description

Technical Field

[0001] This invention relates to a method for efficiently removing sulfonamide antibiotics from flocculent sludge, belonging to the field of wastewater treatment technology. Background Technology

[0002] Antibiotics are a significant component of PPCPs (Protein, Polymer, and Chemical) pollutants, making substantial contributions to medicine, crop growth, and pest control. However, in recent years, the increasing use of antibiotics has adversely affected aquatic plants and animals, and has also had potential impacts on microbial systems and humans (such as the spread of antibiotic resistance genes). Sulfonamide antibiotics (SAs) are synthetic antibacterial agents and are the longest-used synthetic antibiotics in history, becoming one of the most commonly used antibiotics in agriculture and animal husbandry in recent years. Sulfonamides are widely used to treat human and animal diseases and as animal feed additives, offering advantages such as low cost and broad spectrum. Their mechanism of action involves first delaying bacterial cell reproduction, and then inhibiting cell growth by suppressing the production of folic acid required for cell growth, thereby achieving a bacteriostatic effect. Sulfonamide antibiotics are difficult for organisms to completely absorb, and most are excreted in feces and urine. This results in a high detection frequency in various natural water bodies. Residual antibiotics can induce drug resistance in microorganisms and exacerbate the pollution of antibiotic resistance genes (ARGs) in the environment.

[0003] Pharmaceutical and medical wastewater often contains high concentrations of sulfonamide antibiotics. In emergency situations where the discharged wastewater contains high levels of sulfonamides, current technologies struggle to efficiently remove these high concentrations. Biological methods offer advantages such as high efficiency, low operating costs, mild reaction conditions, and environmental friendliness. They primarily remove pollutants through biodegradation. The activated sludge process, used for over 100 years, is currently the most mature aerobic biological treatment technology. However, the traditional activated sludge (CAS) process, commonly used in wastewater treatment, has a low antibiotic removal rate. A survey by Gao Junhong et al. showed that A… 2 In the / O process, the sludge adsorbs and removes 0.6%–2.1% of SAs (antibiotics) and chloramphenicol, which is a low removal rate. Furthermore, A… 2When facing the demand for treating emerging pollutants such as antibiotics, the O2O process may also encounter problems such as insufficient carbon sources and imbalanced nutrient substrate ratios. A study by Li Qingxue et al. on the migration and transformation characteristics of antibiotics in a wastewater treatment plant in Handan City showed that the three-ditch oxidation ditch process achieved biodegradation and adsorption rates of 25.5% and 74.5% for antibiotics (SAs), and 66.7% and 33.3% for β-lactams, respectively. However, the three-ditch oxidation ditch process requires a large land area, and its energy consumption and operating costs increase significantly. The aerated biological filter process achieved biodegradation and adsorption rates of 26.3% and 73.7% for SAs, and 82.1% and 17.9% for β-lactams, respectively. However, the aerated biological filter process has stringent oxygen requirements, mainly referring to the removal of pollutants under aerobic conditions, which results in high energy consumption. Compared to the traditional activated sludge process, the membrane bioreactor (MBR) process can improve antibiotic removal rates by 10% to 65%. Studies have shown that the removal rates of erythromycin, ofloxacin, and sulfamethoxazole in the MBR process can reach 67.3%, 94%, and 60.5%, respectively. Although the MBR process improves the removal efficiency, the use of different types of membranes to degrade pollutants in the membrane bioreactor increases energy consumption, and the cleaning of the membrane after fouling is more complex.

[0004] In existing technologies, aerobic granular sludge is used for acclimation to remove antibiotics, achieving a high removal rate. Aerobic granular sludge is a bioaggregate formed by microbial self-aggregation and the action of external selective pressure (hydraulic shear force, gravity, etc.). It has a certain effect on antibiotic removal, but the initial cultivation time for aerobic granular sludge is relatively long, the aeration conditions are quite demanding, and the resulting aerobic granular sludge also has the risk of easy disintegration. Summary of the Invention

[0005] To address one or more of the aforementioned problems, this invention develops a method for efficiently removing sulfonamide antibiotics by acclimating flocculent sludge using a sequencing batch reactor (SBR). By adjusting the culture conditions of the activated sludge in a conventional activated sludge system, the removal of sulfonamide antibiotics can be significantly improved. The flocculent sludge produced by conventional activated sludge processes contains a large number of sludge flocs; these flocs have a large specific surface area and can interact electrostatically with the ionizable functional groups of antibiotics, thereby adsorbing antibiotics from wastewater into the activated sludge, which are then transferred and removed during subsequent separation of excess sludge. The activated sludge process effectively removes antibiotics and is characterized by its simple operation, low treatment cost, and large-scale operation. Pollutant removal is mainly achieved through sludge adsorption and microbial degradation. Nitrifying bacteria, an important functional bacterium in the activated sludge treatment process, can improve the removal efficiency of drugs including antibiotics through co-metabolism while performing nitrification. Therefore, by inoculating activated sludge and acclimating it into flocculent form, functional bacterial communities can be enriched, and efficient removal of sulfonamide antibiotics can be achieved using these functional bacteria.

[0006] A method for acclimating flocculent sludge with high efficiency in removing sulfonamide antibiotics, the technical solution of which is as follows:

[0007] (1) Add ordinary activated sludge to the SBR reactor and set the operating cycle of the SBR reactor. The reactor works 3 cycles per day, each cycle is 480 min, including 5 min of water influent, 150 min of anaerobic, 270 min of aerobic, 1 min of sludge discharge, 30 min of sedimentation, 5 min of water discharge and 20 min of settling. The water discharge ratio is 4:1.

[0008] (2) Add nitrogen source, phosphorus source, organic carbon source and trace element concentrate to the influent of the reactor and adjust the pH to 7-8;

[0009] (3) Sulfadiazine (SDZ) was gradually added to the influent in six stages in order of increasing concentration. The concentration of SDZ in the influent was 0 mg / L in the first stage, 0.1-0.2 mg / L in the second stage, 0.4-0.6 mg / L in the third stage, 2-3 mg / L in the fourth stage, 8-12 mg / L in the fifth stage, and 0 mg / L in the sixth stage. Each stage was run for 10-13 days to acclimate activated sludge that could stably remove sulfadiazine.

[0010] In one embodiment, (1) the effective volume of the SBR reactor is 5L, the working volume is 4L, the bottom of the reactor is provided with an aeration disc, and the reactor contains a rotor flow meter.

[0011] In one embodiment, in (1), the dissolved oxygen (DO) concentration in the SBR reactor is controlled to be maintained between 2 and 6 mg / L, and the activated sludge concentration (MLSS) is maintained between 1500 and 2500 mg / L.

[0012] In one embodiment, the nitrogen source in (2) is NH4Cl, and the concentration of NH4Cl in the influent is controlled to be 30-60 mg / L.

[0013] In one embodiment, the phosphorus source in (2) is KH2PO4, and the concentration of KH2PO4 in the influent is controlled to be 5-15 mg / L.

[0014] In one embodiment, the organic carbon source in (2) is sodium acetate, and the concentration of sodium acetate in the influent is controlled to be 200-500 mg / L.

[0015] In one implementation, NaHCO3 is used in (2) to adjust the pH value.

[0016] In one embodiment, (2) the amount of trace element concentrate added per liter of influent is 1 mL, and the trace elements per liter consist of 10 g EDTA, 0.12 g ZnSO4·7H2O, 0.15 g CoCl2·6H2O, 0.15 g H2BO3, 0.03 g CuSO4·5H2O, 0.06 g Na2MoO4·2H2O, 1.4 g CaCl2·2H2O, 1.5 g FeCl3·6H2O, 0.88 g MgSO4·7H2O, and 0.18 g KI.

[0017] A method for removing sulfadiazine from wastewater: The above-mentioned acclimated activated sludge is inoculated into different process sections of a wastewater treatment plant. The bacteria enriched in the acclimated flocculent sludge, which have the ability to degrade or adsorb antibiotics, are utilized to remove pollutants from the wastewater by taking advantage of the unique structure of the flocculent sludge. At the same time, more bacteria can be enriched, resulting in a more efficient removal of pollutants.

[0018] The beneficial effects of this invention are:

[0019] (1) This invention uses ordinary activated sludge as inoculation. By setting different conditions, the activated sludge is acclimated into flocs. The sludge flocs have a huge specific surface area, which can interact electrostatically with the ionizable functional groups of antibiotics, thereby allowing the antibiotics in the wastewater to be adsorbed into the activated sludge and then transferred and removed during the subsequent separation of excess sludge. At the same time, the acclimated flocculent sludge has a moderate particle size, strong resistance to shock loads, and the advantage of not easily disintegrating.

[0020] (2) The entire sludge acclimation cycle of this invention is relatively short, and it maintains a stable and good effect in removing basic pollutants such as nitrogen and phosphorus. At the same time, the removal of sulfadiazine also plays an increasingly excellent role in the gradual acclimation process. During the entire acclimation stage, the increase in sludge volume is not significant. This method will not cause a large change in sludge concentration and will not generate a large amount of sludge. If the scale of cultivation is expanded, there is no need to consider the subsequent treatment of sludge, thereby reducing the cost input. It has the advantages of efficient removal of sulfadiazine and small sludge volume.

[0021] (3) The present invention adopts a method of gradually increasing the concentration of sulfadiazine in six stages to control the pH and dissolved oxygen within a reasonable range. In six different time periods, the average removal rate of ammonia nitrogen is as high as 99.2%, which is almost completely removed and has a good effect. When the concentration of sulfadiazine is 0.5 mg / L, the average removal rate increases to 77.8%. The sludge is further acclimated to the next stage. When the concentration of sulfadiazine is increased to 2.5 mg / L and 10 mg / L, the average removal rates of sulfadiazine are 98.5% and 99.5% respectively. Sulfadiazine is almost completely removed and the effect is excellent. The removal rate can reach up to 3.4 mg / L within 2 hours. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the SBR device for acclimating sludge according to the present invention, wherein 1: agitator; 2: inlet; 3: outlet; 4: aeration pump; 5: aeration disc;

[0024] Figure 2 This is a graph showing the changes in ammonia nitrogen concentration and removal rate in the influent and effluent of the SBR at each stage of the present invention.

[0025] Figure 3 This is a graph showing the changes in total nitrogen concentration and removal rate of influent and effluent in each stage of the SBR of this invention;

[0026] Figure 4 This is a graph showing the changes in total phosphorus concentration and removal rate in the influent and effluent of the SBR at each stage of the present invention.

[0027] Figure 5 This is a graph showing the changes in sludge concentration at each stage of the SBR in this invention.

[0028] Figure 6 This is a graph showing the variation in sludge particle size at each stage of the SBR in this invention.

[0029] Figure 7 This is a microscopic image of sludge in the SBR of this invention;

[0030] Figure 8 This is a graph showing the changes in SDZ concentration and removal rate in the influent and effluent of the SBR in this invention at each stage;

[0031] Figure 9 This is a graph showing the concentration changes of SDZ at different times in the fourth stage of the SBR of this invention;

[0032] Figure 10 This is a graph showing the concentration changes of SDZ at different times in the fifth stage of the SBR of this invention. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0034] The technical terms, relevant testing methods, and sources of sludge involved in this application are first introduced as follows:

[0035] 1. SBR reactor used for sludge acclimation:

[0036] like Figure 1 As shown, the reactor used for sludge acclimation is a cylindrical sequencing batch reactor (SBR), 40 cm high, 14 cm inner diameter, with an effective volume of 5 L and a working volume of 4 L. The reactor is equipped with a stirrer 1, with a stirring speed of 250 r / min. An aeration disc 5 is located at the bottom of the reactor, connected to an aeration pump 4, and the DO concentration is controlled at 2-6 mg / L using a rotor flow meter. The reactor sidewall has an inlet 2 and an outlet 3 for inlet and outlet of simulated wastewater. Inlet 2 is located 1 L above the bottom water level, and outlet 3 is located 3 L above the bottom water level.

[0037] 2. Detection method for ammonia nitrogen removal rate: Ammonia nitrogen was determined by Nessler's reagent spectrophotometry.

[0038] 3. Detection method for total nitrogen removal rate: Total nitrogen was determined by alkaline potassium persulfate digestion ultraviolet spectrophotometry.

[0039] 4. Detection method for total phosphorus removal rate: Total phosphorus was determined by ammonium molybdate spectrophotometry.

[0040] 5. Method for detecting sludge concentration: The gravimetric method is used. Take 10 ml of sludge under stirring, weigh the blank filter paper as m1, filter the sludge and place it in a 105℃ oven to dry for 60 min, and record the weight as m2. The unit of weight is mg.

[0041]

[0042] 6. Detection method for sulfadiazine removal rate: The concentration of SDZ was detected by high-performance liquid chromatography (HPLC).

[0043] 7. Sludge source: The sludge was taken from the end of the aeration tank of a sewage treatment plant in Wuxi City.

[0044] Example 1:

[0045] This embodiment provides a method for acclimating flocculent sludge that efficiently removes sulfonamide antibiotics. The method is as follows:

[0046] (1) Add ordinary activated sludge to the sequencing batch reactor (SBR) and set the SBR reactor to work in 3 cycles per day, each cycle being 480 min, including 5 min of influent, 150 min of anaerobic, 270 min of aerobic, 1 min of sludge discharge, 30 min of sedimentation, 5 min of drainage and 20 min of settling, with a drainage ratio of 25%.

[0047] (2) The influent uses NH4Cl as the nitrogen source at a concentration of 50 mg / L; KH2PO4 as the phosphorus source at a concentration of 10 mg / L; sodium acetate as the organic carbon source at a concentration of 500 mg / L; and 125 mg / L NaHCO3 is added to control the pH at 7.8 ± 0.2. 1 mL of a trace element concentrate is added per liter of influent. Each liter of trace element concentrate consists of 10 g EDTA, 0.12 g ZnSO4·7H2O, 0.15 g CoCl2·6H2O, 0.15 g H2BO3, 0.03 g CuSO4·5H2O, 0.06 g Na2MoO4·2H2O, 1.4 g CaCl2·2H2O, 1.5 g FeCl3·6H2O, 0.88 g MgSO4·7H2O, and 0.18 g KI. The composition of the trace elements is shown in Table 1.

[0048] Table 1 Trace element composition of SBR reactor

[0049]

[0050] (3) Sulfadiazine (SDZ) was gradually added to the influent in six stages in order of increasing concentration. The concentration of SDZ in the influent was 0 mg / L in the first stage, 0.1 mg / L in the second stage, 0.5 mg / L in the third stage, 2.5 mg / L in the fourth stage, 10 mg / L in the fifth stage, and 0 mg / L in the sixth stage. Each stage was run for 10 days to acclimate activated sludge that could stably and efficiently remove sulfadiazine.

[0051] The concentrations of ammonia nitrogen, total nitrogen, and total phosphorus in the influent and effluent at different stages of the reactor, and their corresponding removal rates, are as follows: Figure 2 , Figure 3 , Figure 4 As shown, ammonia nitrogen removal remained relatively stable at different stages, with removal rates generally above 99%, averaging 99.2%, indicating excellent denitrification. The average total nitrogen removal rate across all stages was 72.6%. Total nitrogen removal was affected by the addition of sulfadiazine, showing significant fluctuations, especially at a sulfadiazine concentration of 10 mg / L, where the total nitrogen removal rate decreased. The average total phosphorus removal rate across different stages was 72%, with considerable fluctuations in removal efficiency. The addition of sulfadiazine may have caused some harm to the growth of polyphosphate-accumulating bacteria, or it may be due to the lack of sludge removal during reactor operation.

[0052] The sludge particle size and microscopic images at different stages of the reactor are shown below. Figure 5 , Figure 6 As shown, the sludge particle size is basically maintained between 155μm and 170μm, with little fluctuation in particle size, and it is in the form of flocculent sludge; the basic morphology of the sludge is shown in the microscopic image, and the sludge is relatively dispersed and evenly distributed.

[0053] The removal effect of sulfadiazine is as follows Figure 7As shown, sulfadiazine was not added in the initial stage of operation to allow the activated sludge to adapt to the added nitrogen and phosphorus. In the second stage, a low concentration (0.1 mg / L) of sulfadiazine was added. However, the addition of sulfadiazine could cause some harm to the sludge, especially in the stage before the sludge had adapted, resulting in a lower removal rate in the second stage. In the third stage, the concentration of sulfadiazine was increased to 0.5 mg / L. The average removal rate of sulfadiazine in this stage was 77%, which was significantly higher than that in the second stage. In particular, the removal rate of sulfadiazine reached 98% in the later stage of this stage. This shows that the sludge adapted to the stress of sulfadiazine and had a good removal effect on antibiotics such as sulfadiazine while efficiently metabolizing ammonia nitrogen. In the fourth stage, the concentration of sulfadiazine was further increased (2.5 mg / L). In this stage, sulfadiazine was stably removed with excellent results, with an average removal rate of 98.5%, almost completely removed. In the fifth stage, the concentration of sulfadiazine was increased to 10 mg / L. The removal effect remained stable in this stage, and the efficient removal of antibiotics such as sulfadiazine was successfully achieved.

[0054] The removal of sulfadiazine from sludge in the fourth and fifth stages of the reactor was stable. Figure 8 , Figure 9 The concentrations at different time points within the same cycle in these two stages are shown. In the fourth stage, the removal rate of sulfadiazine did not fluctuate much. In the fifth stage, the concentration of sulfadiazine was increased to 10 mg / L, and the removal effect remained stable. On days 53, 56, and 59, the removal amount of sulfadiazine could reach 1.5 mg / L, 2.3 mg / L, and 3.4 mg / L within 2 hours, respectively. The removal rate gradually increased, and the effect was excellent.

[0055] Example 2:

[0056] Using the same method as in Example 1, the difference is that the SDZ concentrations in the influent of the six stages in step (3) of this example are 0, 0.2, 0.6, 3, 12 and 0 mg / L, respectively. The other conditions and parameters are the same as in Example 1, and activated sludge capable of stably and efficiently removing sulfadiazine is obtained through domestication.

[0057] Comparative Example 1

[0058] The same method as in Example 1 was used, except that SDZ was added in four stages in step (3), with concentrations of 0, 1, 2, and 5 mg / L in each stage. The other conditions and parameters were the same as in Example 1. The removal rates of ammonia nitrogen, total nitrogen, total phosphorus, and sulfadiazine in the effluent were tested.

[0059] Comparative Example 2

[0060] The same method as in Example 1 was used, except that SDZ was added in six stages in step (3), with a concentration of 1 mg / L in each stage. The other conditions and parameters were the same as in Example 1. The removal rates of ammonia nitrogen, total nitrogen, total phosphorus, and sulfadiazine in the effluent were tested.

[0061] Comparative Example 3

[0062] Using the same method as in Example 1, except that the SDZ concentrations in the influent of the six stages in step (3) are 0, 4, 6, 8, 12 and 0 mg / L respectively, and the other conditions and parameters are the same as in Example 1, the activated sludge that can stably and efficiently remove sulfadiazine is obtained.

[0063] Comparative Example 4

[0064] The same method as in Example 1 was used, except that in step (1), the SBR reacted for 6 cycles per day, each cycle lasting 240 minutes, including 30 minutes of influent, 30 minutes of anaerobic digestion, 135 minutes of aerobic digestion, 1 minute of sludge removal, 30 minutes of sedimentation, 5 minutes of effluent discharge, and 10 minutes of settling. The effluent discharge ratio was 25%, and the remaining conditions and parameters were the same as in Example 1. The removal rates of ammonia nitrogen, total nitrogen, total phosphorus, and sulfadiazine in the effluent were tested.

[0065] Comparative Example 5

[0066] The same method as in Example 1 was used, except that in step (1), the SBR reacted for 4 cycles per day, each cycle being 360 min, including 30 min of water influent, 60 min of anaerobic digestion, 205 min of aerobic digestion, 1 min of sludge discharge, 30 min of sedimentation, 5 min of drainage, and 30 min of settling. The drainage ratio was 25%, and the remaining conditions and parameters were the same as in Example 1.

[0067] The removal rates of ammonia nitrogen, total nitrogen, and total phosphorus in the effluent of Example 1 and Comparative Examples 1-5, as well as the removal rate of sulfadiazine, were tested.

[0068] Table 1

[0069] example ammonia nitrogen Total nitrogen Total phosphorus sulfadiazine Example 1 99.2％ 72.6％ 72％ 98％ Example 2 97％ 71％ 73％ 95％ Comparative Example 1 98％ 70％ 70％ 92％ Comparative Example 2 99％ 70％ 70％ 90％ Comparative Example 3 90％ 68％ 65％ 85％ Comparative Example 4 85％ 65％ 65％ 80％ Comparative Example 5 87％ 69％ 68％ 84％

[0070] As can be seen from the table, Comparative Example 1, which added sulfadiazine in four stages, showed a 6% reduction in sulfadiazine removal rate compared to Example 1; Comparative Example 2, which added the same concentration of sulfadiazine to the influent during the acclimation process, showed an 8% reduction in sulfadiazine removal rate; Comparative Example 3, which increased the concentration of sulfadiazine too quickly during addition, resulted in lower removal rates of ammonia nitrogen, total nitrogen, total phosphorus, and sulfadiazine in the final water; and Comparative Examples 4 and 5, which changed the SBR reaction conditions, resulted in lower removal rates of ammonia nitrogen, total nitrogen, total phosphorus, and sulfadiazine in the final acclimated sludge compared to Example 1.

[0071] Example 3

[0072] This embodiment provides a method for removing sulfadiazine from wastewater: the activated sludge acclimated in Example 1 is inoculated into different process sections of a wastewater treatment plant. The bacteria enriched in the acclimated flocculent sludge, which have the ability to degrade or adsorb antibiotics, are utilized to remove pollutants from the wastewater by taking advantage of the unique structure of the flocculent sludge. At the same time, more bacteria can be enriched, resulting in a more efficient removal of pollutants.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for high efficiency removal of sulfadiazine by flocculated sludge acclimation, characterized by, The method comprises the following steps: (1) adding common activated sludge in a sequencing batch bioreactor, setting the operation cycle of the reactor, the reactor working for 3 cycles per day, each cycle feeding water for 5 min, anaerobic for 150 min, aerobic for 270 min, sludge discharge for 1 min, sedimentation for 30 min, water discharge for 5 min and standing for 20 min, and the water discharge ratio being 4:1; (2) adding nitrogen source, phosphorus source, organic carbon source and trace element concentrate into the water of the reactor, and adjusting the pH value to 7-8; wherein the nitrogen source is NH4Cl, the concentration of NH4Cl in the water is controlled to be 50 mg / L; the phosphorus source is KH2PO4, the concentration of KH2PO4 in the water is controlled to be 10 mg / L; the organic carbon source is sodium acetate, the concentration of sodium acetate in the water is controlled to be 500 mg / L; the addition amount of the trace element concentrate in each liter of water is 1 mL, and the trace elements in each liter are composed of 10 g EDTA, 0.12 g ZnSO4·7H2O, 0.15 g CoCl2·6H2O, 0.15 g H2BO3, 0.03 g CuSO4·5H2O, 0.06 g Na2MoO4·2H2O, 1.4 g CaCl2·2H2O, 1.5 g FeCl3·6H2O, 0.88 g MgSO4·7H2O and 0.18 g KI; (3) gradually adding sulfadiazine into the water in a concentration increasing manner in six stages, the concentration of sulfadiazine in the water in the first stage is 0 mg / L, the concentration of sulfadiazine in the water in the second stage is 0.1-0.2 mg / L, the concentration of sulfadiazine in the water in the third stage is 0.4-0.6 mg / L, the concentration of sulfadiazine in the water in the fourth stage is 2-3 mg / L, the concentration of sulfadiazine in the water in the fifth stage is 8-12 mg / L, and the concentration of sulfadiazine in the water in the sixth stage is 0 mg / L, each stage is operated for 10-13 days, and the activated sludge capable of stably removing sulfadiazine is obtained through domestication.

2. The method for acclimating flocculent sludge for efficiently removing sulfadiazine according to claim 1, characterized in that, NaHCO3 is used to adjust the pH value in (2).

3. The method for high efficiency removal of sulfadiazine by floc sludge acclimation according to claim 1, characterized in that, The effective volume of the SBR reactor in (1) is 5 L, the working volume is 4 L, the bottom of the reactor is provided with an aeration disc, and the reactor contains a rotor flowmeter.

4. The method for high efficiency removal of sulfadiazine by floc sludge acclimation according to claim 1, characterized in that, The dissolved oxygen concentration in the SBR reactor in (1) is controlled to be 2-6 mg / L, and the activated sludge concentration is controlled to be 1500-2500 mg / L.

5. The activated sludge obtained through domestication by any one of the methods in claims 1-4.

6. A method for removing sulfadiazine from sewage, characterized by, The activated sludge in claim 5 is inoculated into different process sections of a sewage treatment plant for treating sewage, the removal of pollutants in the sewage is realized by the bacteria group with the function of degrading or adsorbing antibiotics enriched in the domesticated flocculent sludge, and the pollutants in the sewage are removed by the unique structure of the flocculent sludge.

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