Method for simultaneous removal of nitrate and degradation of antibiotics by sulfur autotrophic-heterotrophic cooperation

Abstract

The application discloses a method for removing nitrate and degrading antibiotics by sulfur autotrophy-heterotrophy cooperation, which comprises the following steps: (1) taking a SBR reactor, inoculating anoxic sludge from a sewage treatment plant, adding CH3NaS, Na2S2O3 and NaHCO3 in nitrate-containing influent, and performing sludge domestication; (2) after the domestication in step (1) is completed, performing anoxic stirring, introducing nitrate-containing wastewater, adding a solution containing CH3NaS and antibiotics into the reactor, stirring and reacting, measuring the first derivative of ORP, when the first derivative |dORP / dt| is less than or equal to r, repeatedly performing the steps of adding a solution containing CH3NaS and antibiotics, stirring and reacting, and measuring the first derivative of ORP, and when the first derivative |dORP / dt| of the last time is less than or equal to r, performing anaerobic stirring, performing precipitation, drainage and stopping, and completing the domestication of sludge; and (3) introducing wastewater to be treated to remove nitrate and antibiotics. The method can realize efficient removal of nitrate and tolerance to beta-lactam antibiotic stress by sulfur autotrophy-heterotrophy cooperation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sewage treatment, in particular to a method for removing nitrate and degrading antibiotics by sulfur autotrophy-heterotrophy. BACKGROUND

[0002] Antibiotics are widely used in medical, livestock, aquaculture and other fields, but most of the unused antibiotic residues are discharged into the water environment in their original form. The continuous accumulation of these pollutants will threaten environmental safety and human health. Beta-lactam antibiotics are widely used due to their high efficiency, universality, low toxicity and other advantages, accounting for more than 65% of the global antibiotic market, and are potential pollutants in sewage treatment. They have been detected in effluent from sewage plants, aquaculture wastewater, medical wastewater, and rainwater. In addition to antibiotics, these wastewaters usually contain pollutants such as COD, NH4 + -N, TP, etc. After the front-end aerobic treatment, carbon sources need to be further added to remove TN, TP and other pollutants. In addition, the biodegradability of antibiotic pollutants is poor, and they are difficult to completely degrade in the end-of-pipe treatment process, often remaining in the residual sludge and effluent, further causing environmental pollution.

[0003] In addition, the traditional nitrification-denitrification denitrification process also faces problems such as high drug consumption, large amount of residual sludge discharge, long process, high labor cost, etc. Related research on autotrophic denitrification has become one of the hotspots. Sulfur autotrophic denitrification is a promising end-of-pipe advanced denitrification process, with advantages such as high efficiency, no need for carbon source, low sludge production, and resistance to shock loading. Although traditional sulfur autotrophic denitrification usually uses granular solid fillers such as sulfur, calcium sulfide, and pyrite as carriers to build filter bed reactors, it has the advantage of high efficiency, but also has problems such as filter bed clogging, high backwashing energy consumption, high sulfate in effluent, and the need for continuous alkali addition.

[0004] In summary, it is of practical significance to develop an end-of-pipe treatment method that can efficiently and stably remove nitrogen and beta-lactam antibiotics to protect water environmental safety and sustainable development. SUMMARY

[0005] In view of the problem that the existing treatment process cannot effectively treat nitrate and beta-lactam antibiotics at the same time, the present application provides a method for removing nitrate and degrading antibiotics by sulfur autotrophy-heterotrophy, which can achieve efficient removal of nitrate by sulfur autotrophy-heterotrophy and tolerance to beta-lactam antibiotic stress, and has a certain degradation effect on beta-lactam antibiotics such as amoxicillin, procaine and cefozopran, and can be applied to the treatment of various antibiotic-containing wastewater.

[0006] To achieve the above-mentioned purposes, the technical solution adopted by the present application is:

[0007] The application provides a method for removing nitrate and degrading antibiotics by sulfur autotrophy-heterotrophy cooperation, comprising the following steps:

[0008] (1) Sulfur autotrophy-heterotrophy cooperation for removing nitrate: taking an SBR reactor, inoculating anoxic sludge from a sewage treatment plant, adding CH3NaS, Na2S2O3 and NaHCO3 in the influent containing nitrate, and performing sludge domestication;

[0009] (2) Antibiotic stress domestication: after the domestication in step (1) is completed, anoxic stirring is performed, then the influent containing nitrate is introduced, a solution containing CH3NaS and antibiotics is added to the reactor, stirring reaction is performed, the first derivative of ORP is measured, when the first derivative |dORP / dt|≤r, the steps of adding a solution containing CH3NaS and antibiotics, stirring reaction and measuring the first derivative of ORP are repeatedly performed again, when the first derivative |dORP / dt|≤r in the last time, anaerobic stirring is performed, then precipitation, drainage and stopping are performed, and the domestication of the sludge is completed;

[0010] (3) After the sludge is domesticated, the influent containing nitrate and antibiotics is introduced for removal.

[0011] Preferably, in step (1), in the domestication stage, the SBR adopts the operation mode of influent, anoxic stirring, standing, and drainage, and the NO3 X concentration of the influent and effluent is measured every day, and the domestication stage is completed when the removal rate of NO3 - is stabilized at more than 95%.

[0012] Preferably, in step (1), the mass concentration ratio of NO3 - -N, CH3NaS and Na2S2O3 in the influent is 1:0.8-2.5:0.5-1, the NO3 - -N concentration in the influent is 80-120 mg / L, and the NaHCO3 concentration is 200-240 mg / L.

[0013] Preferably, in step (1), in the domestication stage, 1.5-2.5 g / L of KH2PO4, 0.4-0.6 g / L of MgSO4·7H2O and 0.008-0.012 g / L of FeSO4·7H2O are added to the reactor.

[0014] Preferably, in step (1), after the anoxic sludge from the sewage treatment plant is inoculated, the sludge mixed liquid has a suspended solid concentration of 5000-6000 mg / L.

[0015] Preferably, in step (1), the HRT of the SBR reactor is 20-28 h; further preferably, the HRT of the SBR reactor is 22-24 h. In some specific embodiments of the present application, the HRT of the SBR reactor is 24 h, and the water replacement ratio is set to 0.5.

[0016] Preferably, in step (1), the influent is adjusted to a pH of 7.5-8.2 using an acid solution.

[0017] In the domestication of the sulfur autotrophic-heterotrophic synergistic removal of nitrate, Na2S2O3 is used as one of the electron donors, which can preferentially promote the sulfur autotrophic denitrification process and prevent the overgrowth of heterotrophic bacteria. CH3NaS, as an electron donor, not only promotes the sulfur autotrophic-heterotrophic synergistic effect, but also promotes the transfer of substances inside and outside the cell membrane after hydrolysis, speeds up the pollutant metabolism process, and accelerates the start-up process.

[0018] After the completion of the domestication stage of the sulfur autotrophic-heterotrophic synergistic removal of nitrate, multiple antibiotic stress domestications are performed within a single cycle. In this stage, the NO3 - -N concentration of the influent is gradually increased, and logical parameters are used to control the reaction time and dosing. The basic principle of this stage is that multiple antibiotic stresses within a single cycle help the microorganisms to resist the antibiotic stress, and the first derivative of ORP is used as a control parameter for the reaction process, and the electronic donor and antibiotic are dosed multiple times to maintain a sustained response. Traditional single-dose high-concentration antibiotics often produce a large amount of sludge adsorption and may cause toxic effects on microorganisms.

[0019] In addition, after the NO3 - -N concentration of the influent is gradually increased, the single cycle is divided into multiple small cycles, which helps to maintain the enzyme activity of the microorganisms. According to enzyme kinetics, as the substrate concentration decreases, the enzyme reaction rate gradually decreases. After being divided into small cycles, multiple dosing of the electronic donor helps to degrade high-concentration pollutants, and higher enzyme activity helps the microorganisms to degrade antibiotics.

[0020] Preferably, in step (2), the total dosage of CH3NaS is 1.3-3.5 times the mass ratio of NO3 - -N in the influent; and the total dosage of the antibiotic is 1:18-22 times the mass ratio of NO3 - -N in the influent.

[0021] Preferably, in step (2), the solution containing CH3NaS and antibiotics is added, the reaction is stirred, and the first derivative of ORP is measured for 6-7 times.

[0022] Preferably, in step (2), the value of r is in the range of 0-0.1.

[0023] Preferably, in step (2), the antibiotic is a beta-lactam antibiotic.

[0024] Preferably, in step (2), the pre-anoxic stirring time is 25-35 min; and the anaerobic stirring time is 20-30 min.

[0025] Preferably, in step (2), multiple antibiotic stress acclimation cycles can be performed, and the NO3- concentration in the influent is gradually increased in different cycles. - -N concentration.

[0026] Compared with the prior art, the beneficial effects of the present application are:

[0027] (1) Sulfur autotrophy-heterotrophy can be used to remove nitrate and beta-lactam antibiotics efficiently, and can be applied to the end treatment of various antibiotic-containing wastewater.

[0028] (2) Using CH3NaS as a liquid sulfur source and carbon source can promote heterotrophic denitrification and sulfur autotrophic denitrification simultaneously. In addition, sulfur-based has nucleophilicity, metal chelation, redox, etc., which can react with the disulfide bond in the cell membrane to mediate the transfer of substances and accelerate the reaction rate.

[0029] (3) The method of multiple antibiotic stress acclimation in a single cycle helps the microorganisms to respond to antibiotic stress continuously. The sludge adsorption and toxic effects caused by single addition of high-concentration antibiotics are avoided.

[0030] (4) Using the first derivative of ORP |dORP / dt| as a control parameter, the single cycle is divided into multiple small cycles by controlling the addition of electron donors, which helps to maintain the enzyme activity of microorganisms and accelerate the reaction process.

[0031] (5) The strategies of pre-anaerobic stirring and extended stirring after dosing are used to reduce the influence of abnormal peaks on the program progress. In addition, the combination of two judgment cycles improves the accuracy of controlling the reaction end.

[0032] (6) In the antibiotic stress acclimation stage, the nitrate concentration in the influent and the external antibiotic concentration are gradually increased, which helps to simultaneously improve the denitrification load of the reactor and the removal effect of beta-lactam antibiotics.

[0033] (7) Using the heterotrophic-autotrophic combined treatment method, heterotrophic denitrification and sulfur autotrophic denitrification are combined in a single unit to realize the complementation of alkalinity, reduce the dosage of alkalinity, and save the drug consumption. At the same time, it helps to efficiently remove nitrogen and reduces the production of sulfate, avoiding the secondary pollution of sulfur autotrophy.

[0034] (8) Although CH3NaS can promote the sulfur autotrophic-heterotrophic denitrification process well, its aqueous solution is strongly alkaline after being dissolved in water, and if a large amount of it is added at one time when the load is increased, it will cause the microorganisms to be intolerant and die, etc. Traditional split feeding requires multiple sampling, which is too cumbersome. The use of a logic control system can evenly split the feeding and reduce labor costs. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 NO3 - -N removal effect;

[0036] Figure 2 NO3 - -N removal effect;

[0037] Figure 3 SO4 2- yield chart;

[0038] Figure 4 Control logic diagram for single-cycle multiple antibiotic stress domestication operation;

[0039] Figure 5 NO3 - -N and antibiotic stress denitrification effect;

[0040] Figure 6 NO3 - -N and antibiotic stress denitrification effect;

[0041] Figure 7 Comparison of community richness between experimental and control groups. DETAILED DESCRIPTION

[0042] The specific embodiments of the present application will be further described below. It should be noted that the description of these embodiments is used to help understand the present application, but does not constitute a limitation on the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other.

[0043] The experimental methods in the following examples are all conventional methods unless otherwise specified. The test materials used in the following examples are all commercially available unless otherwise specified.

[0044] Example 1

[0045] Start-up denitrification effect of mixed autotrophic-heterotrophic denitrification reactor and traditional reactor.

[0046] The SBR reactor A with effective volume of 10 L was used as experimental group, and the anoxic sludge from the biochemical system of municipal wastewater treatment plant was inoculated for domestication. The suspended solid concentration of sludge mixed liquor after inoculation was about 5000-6000 mg / L. The HRT was set to 24 h, and the water exchange ratio was set to 0.5. The SBR adopted the operation mode of water feeding (10 min), anoxic stirring (11 h), standing (40 min), and water draining (10 min).

[0047] The synthetic wastewater was used for water feeding, and NaNO3 was used to provide NO3 - -N: about 100 mg / L. Sodium methanethiolate (CH3NaS): 150 mg / L, sodium thiosulfate (Na2S2O3): 80 mg / L, and sodium bicarbonate (NaHCO3): 220 mg / L were added in the water feeding. In addition, 2 g / L KH2PO4, 0.5 g / L MgSO4·7H2O, and 0.01 g / L FeSO4·7H2O were added to promote cell growth and reproduction, and 1 mol / L hydrochloric acid was used to adjust the pH of water feeding to 7.5-8.2.

[0048] The upflow fixed bed reactor B with effective volume of 10 L was used as control group, and traditional sulfur granules were used as fixed bed filler. The sludge was inoculated as consistent with the experimental group, and the sludge was mixed uniformly with the sulfur granules before being inoculated into the reactor. The fixed bed was divided into four layers, and water-permeable partitions and flanges were used for connection. A three-phase separator and a reflux pipe were arranged at the top of the fixed bed to return to the water inlet at the bottom of the reactor. The fixed bed adopted the operation mode of water feeding, reflux, standing, and water draining, and the reaction cycle was the same as that of the experimental group. No additional electron donor CH3NaS was added in the water feeding, and the remaining components were consistent with those of the experimental group.

[0049] As shown in Figure 1 , the NO3 - -N removal rate (RE.NO3 - -N) of the experimental reactor A maintained at about 99% after 20 days of operation, while the NO3 - -N removal rate of the control reactor B only reached about 70% ( Figure 2 ). The use of sodium methanethiolate (CH3NaS) and sodium thiosulfate (Na2S2O3) can quickly start the sulfur autotrophic-heterotrophic collaborative denitrification, and has higher denitrification efficiency compared with the traditional sulfur autotrophic filter bed.

[0050] The NO2 - -N in the effluent of the experimental reactor A was almost completely degraded after the 10th day, while the phenomenon of NO2 - -N accumulation (average effluent NO2 - -N > 10 mg / L) occurred in the effluent of the control reactor B. Long-term NO2 - -N accumulation may cause toxic effects on microorganisms.

[0051] In addition, such as Figure 3 Compared to control group B, experimental group A had lower SO4 content. 2- Lower yields may be due to heterotrophic denitrification, and organic electron donors may be used for sulfate reduction, allowing them to participate further in the sulfur cycle for synergistic denitrification.

[0052] Example 2

[0053] Acclimation to multiple antibiotic stresses within a single cycle.

[0054] After day 20, the reactor entered the antibiotic stress acclimatization phase, during which four influent NO3 levels were set. - -N concentrations: 100, 200, 300, 400 mg / L. Corresponding antibiotic stress concentrations were set at: 5, 10, 15, 20 mg / L. Experimental group A used an automatic control system to control the reactor operation according to logic parameter control methods. Total CH3NaS dosage: NO3 - The -N mass ratio is 2.5. Furthermore, the antibiotics are also added in a way that the total dosage is evenly distributed, with one cycle per day.

[0055] Details are as attached Figure 4As shown, 1) the starting unit functions to start the control program. 2) the pre-anoxic stirring unit functions to perform pre-anoxic stirring for 30 min to remove residual NOx from the previous cycle. 3) the water feeding unit functions to feed nitrate synthesis wastewater into the reactor. 4) the dosing unit functions to dose the reactor for the first time after water feeding. 5) the first anoxic stirring unit functions to fully stir for sulfur autotrophic-heterotrophic denitrification, and further, the stage tests the ORP value in the reactor through a sensor and inputs, and then the computer calculates the output |dORP / dt|. 6) the judging unit functions to judge whether the |dORP / dt| value is ≤ the set value r, and if the judging result is "no", it returns to the first anoxic stirring calculation unit for continuous operation, and if the judging result is "yes", it enters the re-dosing unit. 7) the re-dosing unit includes dosing stirring and extended stirring for 15 min, which functions to continue stirring for 15 min after dosing is completed and then enters the stirring calculation unit, and further, it can make the reagent fully mixed while avoiding the influence of the ORP peak value generated during the dosing process on the calculation judging result. 8) the anoxic stirring unit functions to continue anoxic stirring for biochemical reaction and calculation of |dORP / dt|, and the calculation method is consistent with step 5). 9) the secondary judging unit judges in the same way as 6). Further, if the secondary judging unit output result is "no", it returns to the first anoxic stirring unit and calculates |dORP / dt|, and further, if the secondary judging unit output result is "yes", it enters the anaerobic stirring unit. 10) the anaerobic stirring unit functions to perform anaerobic stirring for 10-20 min to end the reaction. 11) the precipitation unit functions to separate sludge and water by standing and precipitation. 12) the drainage unit functions to drain the supernatant after the reaction from the reactor. 13) the stopping unit functions to stop the logic control program.

[0056] In the 6), the set value r ranges from 0 to 0.1.

[0057] The operating conditions of the reactor A are shown in Table 1.

[0058] At the end of each acclimation stage, the antibiotic removal effect of the reactor was evaluated, and after the background value was removed by washing with clean water, the reactor was operated according to the operating conditions of the stage, and the concentration of antibiotics in the effluent was determined to evaluate the pollutant removal effect of the reactor. The concentration of antibiotics in the effluent was determined three times for each stage and the average value was taken. The determination of antibiotics was carried out by solid phase extraction-high performance liquid chromatography method. The water sample was filtered through a 0.22 μm filter membrane, then extracted through an activated HLB column, and then the column was eluted with methanol. The extract and eluate were blown dry to 1 mL with nitrogen and stored in a brown sample bottle. The determination was carried out by high performance liquid chromatography.

[0059] Table 1

[0060]

[0061] The control reactor B used continuous flow of influent water, and the hydraulic retention time was controlled to be 24 h by adjusting the flow rate of the influent pump. The operating conditions of the reactor are shown in Table 2.

[0062] Table 2

[0063]

[0064] Different influent NO3 - - Nitrogen removal effect under antibiotic stress:

[0065] As Figure 5 shown in the experimental group A, the overall nitrogen removal effect remained stable, and the nitrogen removal rate gradually increased with the increase of the influent nitrogen load. During this period, the stress level of the antibiotic also increased synchronously, and the antibiotic level increased to 20 mg / L in the fourth phase, resulting in the occurrence of effluent NO X accumulation, but after 35 days of domestication, the nitrogen removal efficiency of reactor A recovered to 90% at the end of phase IV.

[0066] The nitrogen removal effect of the control group traditional sulfur autotrophic filter bed is shown in Figure 6 , and its nitrogen removal performance was severely damaged with the increase of the stress level of the antibiotic. In the fourth phase, it only maintained about 50% of the nitrogen removal efficiency.

[0067] In summary, the heterotrophic-autotrophic nitrogen removal experimental group has better nitrogen removal performance and impact load resistance. Especially in the face of β-lactam antibiotic stress, the experimental group shows better nitrogen removal efficiency and higher nitrogen removal rate.

[0068] Antibiotic removal effect:

[0069] The experimental group has much better antibiotic removal effect than the control group B, which is due to the use of logical control dosing method, which adds antibiotics in small amounts for multiple times, so that the microorganisms have more sufficient adaptation time within the reaction period. In addition, the experimental group adopts the form of activated sludge, and the microorganisms contact with the antibiotic more uniformly to prevent the local concentration from being too high to cause sterilization. In addition, the experimental group adopts heterotrophic-autotrophic denitrification combination to form mixed colonies with stronger antibiotic resistance.

[0070] Comparison of Alpha diversity of microbial community:

[0071] The inoculated sludge, the sludge sample of experimental group A on the 130th day, and the sludge sample of control group B on the 130th day were subjected to high-throughput sequencing analysis of microbial diversity information. The mixed liquid was directly extracted from the reactor, centrifuged and washed, and then stored at -20℃. The sulfide particles in the control group B column were extracted, centrifuged, washed and stored.

[0072] As shown in Table 3, the coverage index in the sludge sample is higher than 0.99. The diversity index of experimental group A is significantly increased compared with the inoculated sludge, indicating the increase of microbial community richness, while the population richness of control group B is significantly declined. This indicates that compared with traditional sulfur autotrophic denitrification, the heterotrophic-autotrophic combined denitrification establishes a more abundant microbial community, which can effectively resist antibiotic stress.

[0073] Table 3

[0074] Sample\Estimators ace chao coverage shannon sobs Inoculum Sludge 567.182 574.067 0.999 5.011 670 Experimental Group A 696.004 714.132 0.999 5.845 813 Control Group B 412.031 403.426 0.999 3.897 516

[0075] Comparison of community richness at genus level:

[0076] The community evolution and dominant dominant bacteria of the experimental group and the control group are further analyzed by comparing the community richness at genus level. The results are shown in Table 5: Figure 7 Compared with the inoculated sludge, significant community evolution occurs in the experimental group and the control group. Sulfurimonas, Acinetobacter and Sphingobium are the top three dominant genera in the experimental group, among which Sulfurimonas is a typical sulfur autotrophic bacteria that is significantly enriched in the experimental group with a relative abundance of 40.76%. In addition, Acinetobacter is related to heterotrophic denitrification, and Sphingobium is related to the degradation of β-lactam antibiotics. The effective enrichment of these genera indicates the effective cooperation of autotrophic-heterotrophic combined denitrifying bacteria in the experimental group, and the directional enrichment of effective genera in the community under the stress of β-lactam antibiotics.

[0077] Example 3

[0078] Long-term stable operation experiment

[0079] The experimental reactor A is adjusted to the working condition of stage III, the influent NO3--N is maintained at 300 mg / L, the daily antibiotic stress level is 15 mg / L, and the stable operation is maintained for 50 days. The influent and effluent nitrogen is measured every day, and the antibiotic removal effect is measured every 10 days. The experimental results are shown in Table 4: In the 50-day long-term operation, the reactor shows stable denitrification performance and antibiotic removal effect, indicating that the autotrophic-heterotrophic combined denitrification method can effectively remove pollutants and has the potential to be applied to the end treatment of wastewater containing β-lactam antibiotics. Table 4

[0080]

[0081] The embodiments of the present application are described in detail above, but the present application is not limited to the described embodiments. Various changes, modifications, replacements, and variations of the embodiments can be made by those skilled in the art without departing from the principles and spirit of the present application, and still fall within the scope of the present application.

Claims

1. A method for simultaneous removal of nitrate and degradation of antibiotics by sulfur autotrophic-heterotrophic cooperation, characterized in that, The method comprises the following steps: (1) Sulfur autotrophic-heterotrophic cooperative removal of nitrate domestication: taking a SBR reactor, inoculating anoxic sludge from a sewage treatment plant, adding CH3NaS, Na2S2O3 and NaHCO3 to the influent containing nitrate, and domesticating the sludge; (2) Antibiotic stress domestication: after the domestication in step (1) is completed, anoxic stirring is performed, then the reactor is fed with a solution containing CH3NaS and antibiotics, stirring reaction is performed, the first derivative of ORP is measured, and when the first derivative |dORP / dt|≤r, the steps of adding a solution containing CH3NaS and antibiotics, stirring reaction, and measuring the first derivative of ORP are repeatedly performed for multiple times; when the first derivative |dORP / dt|≤r in the last time, anaerobic stirring is performed, then sedimentation, drainage and stopping are performed, and the domestication of the sludge is completed; (3) After the sludge is domesticated, the wastewater to be treated is fed to remove nitrate and antibiotics.

2. The method for simultaneous removal of nitrate and degradation of antibiotics by sulfur autotrophic-heterotrophic synergy according to claim 1, characterized in that, In step (1), the acclimation stage, the SBR adopts the operation mode of influent, anoxic agitation, standing, and effluent, and the NO3 X concentration of the influent and effluent is measured every day, and the acclimation stage is completed when the NO3 - -N removal rate is stabilized at more than 95%.

3. The method for simultaneous removal of nitrate and degradation of antibiotics by sulfur autotrophic-heterotrophic synergy according to claim 1, characterized in that, In step (1), the mass concentration ratio of NO3 - -N, CH3NaS, Na2S2O3 is 1:0.8-2.5:0.5-1; the mass concentration ratio of NO3 - -N is 80-120 mg / L; the mass concentration of NaHCO3 is 200-240 mg / L.

4. The method for simultaneous removal of nitrate and degradation of antibiotics by sulfur autotrophic-heterotrophic synergy according to claim 1, characterized in that, In step (1), 1.5-2.5 g / L of KH2PO4, 0.4-0.6 g / L of MgSO4·7H2O and 0.008-0.012 g / L of FeSO4·7H2O are added to the reactor in the domestication stage.

5. The method for simultaneous removal of nitrate and degradation of antibiotics by sulfur autotrophic-heterotrophic synergy according to claim 1, characterized in that, In step (1), after the anoxic sludge from the sewage treatment plant is inoculated, the suspended solid concentration of the sludge mixed liquor is 5000-6000 mg / L.

6. The method for simultaneous removal of nitrate and degradation of antibiotics by sulfur autotrophic-heterotrophic synergy according to claim 1, characterized in that, In step (1), the HRT of the SBR reactor is 20-28 h.

7. The method for simultaneous removal of nitrate and degradation of antibiotics by sulfur autotrophic-heterotrophic synergy according to claim 1, characterized in that, In step (2), the total amount of CH3NaS added is 0.5-2.5 times the amount of NO3 - - N mass ratio is 1.3-3.5:1; the total amount of antibiotics added is 0.5-2.5 times the amount of NO3 - - N mass ratio is 1:18-22.

8. The method for simultaneous removal of nitrate and degradation of antibiotics by sulfur autotrophy-heterotrophy according to claim 1, characterized in that, In step (2), the steps of adding a solution containing CH3NaS and antibiotics, stirring reaction, and measuring the first derivative of ORP are performed for 6-7 times.

9. The method for simultaneous removal of nitrate and degradation of antibiotics by sulfur autotrophic-heterotrophic synergy according to claim 1, characterized in that, In step (2), the value of r ranges from 0 to 0.

1.

10. The method for simultaneous removal of nitrate and degradation of antibiotics by sulfur autotrophic-heterotrophic synergy according to claim 1, characterized in that, In step (2), the antibiotic is a β-lactam antibiotic.

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