A land-saving method for treating anti-corrosion cosmetic surgery wastewater

Abstract

The present invention discloses a land-saving method for treating anti-corrosion and cosmetic surgery wastewater, and belongs to the field of water treatment technology. The present invention cultivates aerobic granular sludge, domesticates AGS under low carbon-nitrogen ratio conditions, and treats anti-corrosion and cosmetic surgery wastewater, and studies the degradation effect of potassium sorbate and nisin in anti-corrosion and cosmetic surgery wastewater. The use of AGS to treat anti-corrosion and cosmetic surgery wastewater occupies a small area, has good adaptability to water quality, and has stable effluent water quality. Good denitrification and phosphorus removal effects can be achieved by relying solely on the AGS process. In addition, the special structure of AGS has a good stress resistance effect on potassium sorbate and nisin preservatives in anti-corrosion and cosmetic surgery wastewater, and has a good degradation effect on both potassium sorbate and nisin.

Description

Technical Field

[0001] The invention belongs to the technical field of water treatment and relates to a land-saving method for treating anti-corrosion cosmetic wastewater. Background Art

[0002] After death, human remains not only accumulate and concentrate a wide variety of toxic and harmful elements and compounds on the Earth's surface, but also contain a large number of bacteria, viruses, pathogenic parasites, and other pathogens that are harmful to the human body. The harmful gases and pathogens released by the remains themselves also pollute various environments to varying degrees. Therefore, in most funeral homes in China, bodies undergo a certain level of embalming treatment upon arrival. During this treatment process, various processing steps generate certain pollution sources, such as wastewater after cleaning the body, the volatilization of preservatives and the discharge of blood and fluid from the body, and body fluids from damaged bodies in abnormal conditions. In particular, during the initial treatment of the body (cleaning and disinfection) and secondary treatment (thawing the body after refrigeration and freezing, and the medical preservation process), a large amount of wastewater is generated. Direct discharge into the receiving water body can pollute the surrounding water quality and cause varying degrees of damage to the surrounding environment. In addition, the early construction planning of funeral homes is insufficient, funeral workers lack environmental awareness, and most funeral homes are located in suburban areas and cannot be connected to the municipal sewage network, resulting in the sewage from the body handling process being discharged untreated, causing water pollution.

[0003] Embalming wastewater is a type of wastewater unique to funeral facilities. This type of wastewater consists of five parts: preservative wastewater, body thawing water, body washing water, container equipment rinsing water, and cosmetic wastewater. This type of wastewater contains three types of pollutants that require special attention: (1) nitrogen and phosphorus pollutants. These pollutants are relatively common, but due to the relatively low concentration of organic matter in the influent, the denitrification and phosphorus removal process based on microbial methods often has poor operation effects; (2) water microbial pollution, which has the disadvantages of widespread distribution and enhanced toxicity of pathogenic bacteria. Among them, Proteobacteria and Bacillus are relatively abundant, and there is even a phenomenon of the growth of a large number of pathogenic microbial groups; (3) embalming wastewater contains persistent and difficult-to-degrade special pollutants such as cosmetics and preservatives. The main components include potassium sorbate, nisin, sodium fatty alcohol ether sulfate (AES), cocopropyl betaine, parachloromethane (PCMX), coconut oil diethanolamide, flavors, glycerin, etc. Although the concentration of this type of wastewater is low, it poses significant environmental and health risks due to its biological toxicity, environmental persistence and bioaccumulation. It can have a toxic effect on subsequent treatment processes and even paralyze the biochemical treatment process.

[0004] Potassium sorbate is a synthetic, colorless, odorless, and inexpensive preservative. It's often added to foods as a preservative to prevent the growth of fungi and mold. Many beauty products prone to mold and spoilage also use this preservative to extend their shelf life, including shampoos, hair sprays, and skin creams. It works by slowing the growth of mold and yeast, thereby extending the shelf life of products, but it can also inhibit the growth of beneficial bacteria. Excessive potassium sorbate can disrupt the human gut microbiome, leading to weakened immunity, liver disease, anxiety, and depression. It can also affect metabolism, causing excess fat to be stored in the body and unable to be excreted, indirectly contributing to obesity and other unhealthy body shapes in children. Furthermore, potassium sorbate can reduce the body's absorption of vitamins and calcium, leading to liver damage and increased cancer rates. The risks posed by potassium sorbate in cosmetic surgery wastewater to human health and the environment cannot be ignored.

[0005] Nisin is a natural, highly effective, and safe bioactive antimicrobial peptide produced through microbial fermentation technology using protein raw materials and fermentation by Streptococcus acidophilus. Nisin works by interfering with the formation of the peptidoglycan layer in the bacterial cell wall, halting the synthesis of phospholipid compounds, the cell wall, and the plasma membrane, leading to the leakage of cellular contents and ATP. Cell lysis effectively inhibits the growth and reproduction of Gram-positive bacteria (including spores), such as Streptococcus, Lactobacillus, and Staphylococcus, but generally has no inhibitory effect on Gram-negative bacteria, fungi, and viruses. Nisin is often combined with other natural biological preservatives or chelating agents to synergistically enhance its antiseptic efficacy and significantly increase its antimicrobial properties. Nisin, as a preservative, has been included in the 2015 edition of the "Catalogue of Used Cosmetic Ingredients." It is widely used in cleansers, creams, masks, lotions, toners, serums, eye and lip care products, and hair care products. In these cosmetics, nisin is synergized with chelating agents to form a preservative system. Although nisin is a natural, highly effective, and safe preservative, long-term and excessive intake of nisin may cause irritation and burden to the gastrointestinal mucosa, leading to gastrointestinal dysfunction. While preservatives inhibit or kill pathogens, they may also inhibit the activity of beneficial microorganisms, deteriorating the microecological environment and disrupting or even blocking the material and energy cycles of the ecosystem. The environmental pollution caused by the inappropriate discharge of wastewater from cosmetic surgery can also harm human health through the food chain.

[0006] Aerobic granular sludge (AGS) has the advantages of dense structure, good sedimentation performance, rich microbial population, and resistance to shock loads. Therefore, it has the advantages of good mud-water separation effect, can treat high-concentration toxic and harmful wastewater, and simultaneously remove nitrogen and phosphorus. It has broad application prospects in the field of wastewater treatment. Anti-corrosion cosmetic wastewater contains three types of pollutants that need to be paid attention to: (1) nitrogen and phosphorus pollution; (2) water microbial pollution; (3) special pollutants with persistent and difficult-to-degrade characteristics such as cosmetics and preservatives pollution. Aerobic granular sludge has a dense structure and has a high anti-diffusion ability for external toxic and harmful substances. Therefore, the cells as a whole have a high tolerance to toxic substances. Aerobic granular sludge with a smooth surface, large particle size and good performance can achieve better sewage treatment effect, can achieve simultaneous and efficient nitrogen and phosphorus removal, and maintain good organic matter removal effect and toxic and harmful substance removal effect. In addition, in recent years, AGS has also shown advantages in removing emerging pollutants, indicating that AGS has the potential to treat embalming and cosmetic surgery wastewater and the ability to remove preservatives potassium sorbate and nisin. Summary of the Invention

[0007] Technical issues:

[0008] Funeral homes are often overlooked due to their unique environments, making pollution prevention and control a weak link. Funeral homes generate large amounts of wastewater during the autopsy, cleaning, and embalming processes. This wastewater contains body fluids, preservatives, and other components. In addition to conventional pollutants, it also contains many toxic organic pollutants and a large number of bacteria, viruses, and resistance genes that may pose a risk of biological leakage. Direct discharge into water bodies will cause varying degrees of pollution to the surrounding environment. With the country's increasing emphasis on pollution control of the ecological environment, strict treatment of embalming and cosmetic wastewater is beneficial to protecting the funeral environment, better preventing and controlling the occurrence and spread of infectious diseases, and is of great significance to protecting the health of funeral workers and the families of the deceased, as well as maintaining a good ecological environment within funeral homes. However, no research has yet been conducted on embalming and cosmetic wastewater.

[0009] Technical solution:

[0010] The present invention takes anti-corrosion and cosmetic surgery wastewater as an example, and utilizes aerobic granular sludge (AGS) technology to remove preservatives such as potassium sorbate and nisin in the anti-corrosion and cosmetic surgery wastewater while ensuring that the wastewater meets discharge standards.

[0011] The present invention provides a method for preparing aerobic granular sludge capable of removing preservatives in wastewater, comprising the following steps:

[0012] (1) Add wastewater and inoculated sludge into the SBR reactor;

[0013] (2) The operating cycle is controlled to be 3.5-4 hours, including 3-5 minutes of water inlet, 210-240 minutes of aeration time, 2-5 minutes of static sedimentation, 2-5 minutes of drainage, 40-60% drainage ratio, 20-30°C reactor temperature, start the reactor, and maintain the aeration volume at 0.05-0.2m 3 / h, and completely granulated AGS was obtained after 35 to 45 days of culture;

[0014] (3) Reduce the influent COD, do not change other operating conditions, and acclimate for 40 to 50 days to obtain acclimated AGS;

[0015] (4) The influent is replaced with anti-corrosion cosmetic wastewater, and other operating conditions are not changed. The culture is carried out for 5 to 9 days, and finally aerobic granular sludge capable of removing preservatives in the wastewater is obtained.

[0016] Furthermore, in step (1), the height-to-diameter ratio of the SBR reactor is 8 to 12:1.

[0017] Specifically, in step (1), the height-to-diameter ratio of the SBR reactor is 10:1.

[0018] Furthermore, in step (1), the wastewater includes sodium acetate, sodium propionate, NH4Cl, K2HPO4, KH2PO4, MgSO4, CaCl2, ETDA and trace element concentrate; wherein the concentration of sodium acetate is 178.8 to 200 mg·L -1 The concentration of sodium propionate is 447-497 mg·L -1 The concentration of NH4Cl is 210-230 mg·L -1 The concentration of potassium hydrogen phosphate is 40~44.8mg·L -1 The concentration of potassium dihydrogen phosphate is 35-35.84 mg·L -1 The concentration of magnesium sulfate is 80-97 mg·L -1 The concentration of calcium chloride is 70-75 mg·L -1 The concentration of EDTA is 7-10 mg·L -1 The concentration of trace element concentrate is 1.44~2.62μg·L -1 .

[0019] Specifically, in step (1), the concentration of sodium acetate in the wastewater is 178.92 mg·L -1 ; The concentration of sodium propionate is 447.3 mg·L -1 ; The concentration of NH4Cl is 618.84 mg·L -1 ; The concentration of K2HPO4 is 40.32 mg·L -1 ; The concentration of KH2PO4 is 32.04 mg·L -1; The concentration of MgSO4 is 174.6 mg·L -1 ; The concentration of CaCl2 is 67.5 mg·L -1 ; EDTA concentration is 18 mg·L -1 .

[0020] Furthermore, the trace element concentrate includes ferric chloride, boric acid, copper sulfate, potassium iodide, manganese chloride, zinc chloride, cobalt chloride and sodium molybdate. In artificial simulated synthetic wastewater, the concentration of ferric chloride is 1-1.5 μg·L -1 The concentration of boric acid is 0.12-0.15 μg·L -1 The concentration of copper sulfate is 0.02-0.03 μg·L -1 The concentration of potassium iodide is 0.02-0.03 μg·L -1 The concentration of manganese chloride is 0.10~0.12μg·L -1 The concentration of zinc chloride is 0.04~0.058μg·L -1 The concentration of cobalt chloride is 0.10~0.15μg·L -1 , the concentration of sodium molybdate is 0.04~0.06μg·L -1 .

[0021] Specifically, the concentration of FeCl3·6H2O in the trace element concentrate is 1.35 μg·L -1 ; The concentration of H3BO3 is 0.135μg·L -1 The concentration of CuSO4·5H2O is 0.027 μg·L -1 ; The concentration of KI was 0.027 μg·L -1 ; The concentration of MnCl2·4H2O is 0.108μg·L -1 ; The concentration of ZnCl is 0.0522 μg·L -1 ; The concentration of CoCl2·6H2O is 0.135μg·L -1 ; The concentration of Na2MoO4·2H2O is 0.054μg·L -1 .

[0022] Furthermore, in step (1), the COD, NH4-N and TP concentrations of the wastewater are 500-600 mg / L, 50-60 mg / L and 10-20 mg / L.

[0023] Specifically, in step (1), the COD, NH4-N and TP concentrations of the wastewater are 550 mg / L, 55 mg / L and 15 mg / L.

[0024] Furthermore, in step (1), the suspended solids concentration of the mixed solution of the inoculated sludge is 4 to 6 g / L.

[0025] Specifically, in step (1), the suspended solids concentration of the mixed liquor of the inoculated sludge is 5 g / L.

[0026] Furthermore, in step (1), the volume ratio of wastewater to inoculated sludge is 1:0.5-3.

[0027] Specifically, in step (1), the volume ratio of wastewater to inoculated sludge is 1:2.

[0028] Furthermore, in step (1), the volume ratio of wastewater to SBR reactor is 1:3-6.

[0029] Specifically, in step (1), the volume ratio of wastewater to SBR reactor is 1:4.5.

[0030] Furthermore, the water in the cycle in step (2) is the wastewater described in step (1).

[0031] Specifically, in step (2), the operation cycle is controlled to be 4 hours, the water inlet time is 3 minutes, the aeration time is 230 minutes, the static sedimentation time is 4 minutes, the drainage time is 3 minutes, the drainage ratio is 50%, the sludge age is 25 days, and the reactor temperature is 25°C.

[0032] Specifically, in step (2), the aeration volume after the reactor is started is 0.12m 3 / h.

[0033] Specifically, optionally, in step (2), the culture time of the aerobic granular sludge is 40 days.

[0034] Furthermore, in step (3), the influent COD is reduced to 100-160 mg / L.

[0035] Specifically, optionally, in step (3), the influent COD is reduced to 140 mg / L.

[0036] Specifically, optionally, in step (3), the acclimation time of the aerobic granular sludge is 48 days.

[0037] Furthermore, in step (4), the anti-corrosion cosmetic wastewater is prepared by adding 3 to 7 ug / L of potassium sorbate and 6 to 10 ug / L of nisin to the wastewater described in step (1).

[0038] Specifically, in step (4), the antiseptic cosmetic wastewater is the wastewater described in step (1) with 5ug / L of potassium sorbate and 8ug / L of nisin added thereto.

[0039] Specifically, in step (4), the culture time is 7 days.

[0040] Furthermore, the particle size of the aerobic granular sludge capable of removing preservatives in wastewater prepared in step (4) is between 0.5 mm and 0.8 mm.

[0041] The present invention provides aerobic granular sludge prepared according to the above steps.

[0042] The aerobic granular sludge provided by the present invention is used in wastewater treatment.

[0043] Furthermore, the uses include denitrification and dephosphorization of wastewater, COD removal, heavy metal adsorption, and preservative removal.

[0044] Furthermore, the preservative includes potassium sorbate and / or nisin.

[0045] The present invention provides an application of the aerobic granular sludge prepared above to treat preservatives in wastewater, comprising the following steps:

[0046] Take aerobic granular sludge and anti-corrosion cosmetic wastewater, mix them, stir and aerate, and treat for 20 to 28 hours.

[0047] Furthermore, the stirring speed is 150-200 rpm.

[0048] Furthermore, the aeration volume is between 0.05 and 0.2 m 3 / h.

[0049] Furthermore, the antiseptic cosmetic wastewater is wastewater containing potassium sorbate and / or nisin.

[0050] Preferably, the antiseptic cosmetic wastewater is wastewater containing 3 to 7 ug / L of potassium sorbate and 6 to 10 ug / L of nisin.

[0051] The present invention provides a land-saving method for treating anti-corrosion cosmetic surgery wastewater, comprising the following steps:

[0052] (1) Add wastewater and inoculated sludge into the SBR reactor;

[0053] (2) The operating cycle is controlled to be 3.5-4 hours, including 3-5 minutes of water inlet, 210-240 minutes of aeration time, 2-5 minutes of static sedimentation, 2-5 minutes of drainage, 40-60% drainage ratio, 20-30°C reactor temperature, start the reactor, and maintain the aeration volume at 0.05-0.2m 3 / h, and completely granulated AGS was obtained after 35 to 45 days of culture;

[0054] (3) Reduce the influent COD, do not change other operating conditions, and acclimate for 40 to 50 days to obtain acclimated AGS;

[0055] (4) replacing the influent with preservative cosmetic wastewater without changing other operating conditions, culturing for 5 to 9 days, and finally obtaining aerobic granular sludge capable of removing preservatives from the wastewater;

[0056] (5) Mix the aerobic granular sludge and the anti-corrosion cosmetic wastewater, stir and aerate, and treat for 20 to 28 hours.

[0057] Beneficial effects:

[0058] (1) The present invention only requires injecting wastewater into a reactor containing aerobic granular sludge and aerating it to obtain wastewater that meets emission standards. The wastewater treatment method is simple, low-cost, and highly operable.

[0059] (2) The treatment method of the present invention has a strong purification ability. When treating wastewater containing potassium sorbate, the removal rates of COD, TN, TP and potassium sorbate within 24 hours are 91.93%, 86.92%, 76.67% and 80.40%, respectively. When treating wastewater containing nisin, the removal rates of COD, TN, TP and nisin within 24 hours are 92.57%, 87.60%, 77.22% and 77.50%, respectively.

[0060] (3) When low carbon-nitrogen ratio wastewater is used to acclimate the aerobic granular sludge (AGS) cultured using the method of the present invention, the aerobic granular sludge can achieve simultaneous and efficient nitrogen and phosphorus removal without undergoing a long adaptation period. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 Schematic diagram of the SBR reactor (1. Water inlet tank; 2. Water inlet pump; 3. Solenoid valve; 4. Air compressor; 5. Gas flow meter; 6. Microporous aeration head; 7. SBR; 8. Sampling port; 9. Water outlet; 10. Water outlet tank; 11. Time control system).

[0062] Figure 2 The removal effect of AGS on COD, TN and TP in anti-corrosion and cosmetic wastewater.

[0063] Figure 3 This is the removal effect of AGS on COD, TN, TP and potassium sorbate after adding potassium sorbate.

[0064] Figure 4 This is the removal effect of AGS on COD, TN, TP and nisin after adding nisin. DETAILED DESCRIPTION

[0065] Source of raw materials:

[0066] Potassium sorbate (Brand: McLean, Product No.: P856768, Purity: 98%) and nisin (Brand: TargetMol, Product No.: TP1329, Purity: 98%) were purchased from Cheyuan.com. Unless otherwise specified, other raw materials used in the present invention were commercially available.

[0067] Example 1

[0068] (1) Cultivation of granulated AGS

[0069] Taken from a sewage treatment plant A 2 The activated sludge from the aerobic tank of the / O process was used as the inoculation sludge, with an inoculation volume of 2 L and a suspended solid concentration of 5.0 g / L in the mixed liquor of the inoculation sludge.

[0070] The test influent was artificial simulated synthetic wastewater, which was transported into the reactor by a peristaltic pump with an inlet volume of 1 L. The artificial simulated synthetic wastewater included sodium acetate, sodium propionate, NH4Cl, K2HPO4, KH2PO4, MgSO4, CaCl2, ETDA, and trace element concentrate, of which the concentration of sodium acetate was 178.92 mg·L -1 ; The concentration of sodium propionate is 447.3 mg·L -1 ; The concentration of NH4Cl is 618.84 mg·L -1 ; The concentration of K2HPO4 is 40.32 mg·L -1 ; The concentration of KH2PO4 is 32.04 mg·L -1 ; The concentration of MgSO4 is 174.6 mg·L -1 ; The concentration of CaCl2 is 67.5 mg·L -1 ; EDTA concentration is 18 mg·L -1 The trace element concentrate includes FeCl3·6H2O, H3BO3, CuSO4·5H2O, KI, MnCl2·4H2O, ZnCl, CoCl2·6H2O and Na2MoO4·2H2O, among which the concentration of FeCl3·6H2O is 1.35μg·L -1 ; The concentration of H3BO3 is 0.135μg·L -1 The concentration of CuSO4·5H2O is 0.027 μg·L -1 ; The concentration of KI was 0.027 μg·L -1 ; The concentration of MnCl2·4H2O is 0.108μg·L -1 ; The concentration of ZnCl is 0.0522 μg·L -1 ; The concentration of CoCl2·6H2O is 0.135μg·L -1 ; The concentration of Na2MoO4·2H2O is 0.054μg·L-1 The COD, NH4-N and TP concentrations of the influent were 550 mg / L, 55 mg / L and 15 mg / L.

[0071] The experimental device uses an SBR reactor with the following dimensions: inner diameter 11 cm, height 110 cm, effective volume 4.5 L, and aeration rate controlled by a rotor flowmeter. The operation changes of each stage of the reactor are controlled by a time controller. The switch control operation cycle is 4 hours, including 3 minutes of water inlet, 230 minutes of aeration time, 4 minutes of static sedimentation, 3 minutes of drainage, a drainage ratio of 50%, a sludge age of 25 days, and a reactor temperature of 25°C. The device is as follows Figure 1 shown.

[0072] After the reactor is started, the aeration volume is maintained at 0.12m 3 / h. The goal is to acclimate the sludge to the reactor environment, quickly forming AGS under high shear and hydraulic selective pressure, and achieving excellent nitrogen and phosphorus removal. After 40 days of incubation, fully granulated AGS is obtained. The particle size of the granulated AGS ranges from 0.5mm to 0.8mm.

[0073] (2) Acclimation of granulated AGS

[0074] After the granular AGS is successfully cultivated, the influent COD concentration is reduced to 140 mg / L, and low carbon-nitrogen ratio sewage treatment is acclimated for 48 days without changing other operating conditions, so that the microorganisms in the reactor can adapt to the low-concentration organic environment and obtain acclimated aerobic granular sludge.

[0075] Since AGS did not undergo a long adaptation period, the average removal rates of COD, TN and TP were calculated to be 78.46%, 63.28% and 67.66% according to the data in Tables 1 and 2 below, indicating that AGS still has good nitrogen and phosphorus removal effects under low carbon-nitrogen ratio conditions.

[0076] Table 1 Design influent water quality

[0077]

[0078] Table 2 Designed effluent quality

[0079]

[0080] (3) Adaptation of granulated AGS

[0081] The domesticated AGS was used to treat the anti-corrosion and cosmetic surgery wastewater. The laboratory artificially prepared the anti-corrosion and cosmetic surgery wastewater. The artificial preparation of the anti-corrosion and cosmetic surgery wastewater was based on artificially simulated synthetic wastewater and added potassium sorbate and nisin to it to make the final concentrations of 5ug / L and 8ug / L. Without changing other operating conditions, the water output indicators measured after one week of cultivation in the reactor all met the Class A standard of the "Pollutant Discharge Standard for Urban Wastewater Treatment Plants" (GB18918-2002). The pollutant removal effect within one week of the reactor operation is shown in Table 3 and Figure 2 As shown in the figure, AGS has an adaptation period to the change of water quality conditions. After one week of cultivation, the pollutant removal effect of AGS has increased significantly. The removal rates of COD, TN and TP increased from 71.43%, 50.84% ​​and 62.65% on the 0th day to 92.57%, 87.76% and 76.67% respectively.

[0082] Table 3 Removal effect of various indicators

[0083]

[0084] Example 2

[0085] Take the AGS that has been adapted in Example 1, add 100mL of AGS to the new reactor, control the MLSS to be about 2.5g / L, and then add the artificially prepared anti-corrosion cosmetic wastewater to 500mL. Add 2.5ug of potassium sorbate to make its final concentration 5ug / L. Each group of experiments has three parallel samples, and magnetic stirring is used to stir so that the mud and water in each conical flask are fully mixed, and the speed is 180rpm. Use an aeration device to aerate it, and the aeration volume is maintained at 0.12m 3 / h, and water samples were taken for testing at the end of the 0h, 1h, 3h, 6h, 9h, 12h, and 24h cycles respectively.

[0086] Pretreatment of water sample testing: Take 1 mL of water sample, add 1 mL of methanol and mix well, filter through 0.22 μm polytetrafluoroethylene (PTFE) membrane, and analyze by UPLC-MS / MS. The water index and potassium sorbate concentration are shown in Table 4 and Figure 3 As shown in the data, with the increase of reaction cycle, the removal effect of AGS on potassium sorbate improved significantly. At 24 h, the removal rates of COD, TN, TP and potassium sorbate were 91.93%, 86.92%, 76.67% and 80.40%, respectively. AGS can resist the toxicity of potassium sorbate, and may have a good removal effect through adsorption and degradation.

[0087] Table 4 AGS removal effect on potassium sorbate

[0088]

[0089] Example 3

[0090] Take the AGS that has been adapted in Example 2, add 100mL of AGS to the new reactor, control the MLSS to be about 2.5g / L, and then add the artificially prepared anti-corrosion cosmetic wastewater to 500mL. Add 4ug of nisin to make its final concentration 8ug / L. Three parallel samples are set for each group of experiments. Magnetic stirring is used to stir so that the mud and water in each conical flask are fully mixed. The speed is 200rpm. Use an aeration device to aerate it, and the aeration volume is maintained at 0.12m 3 / h, and water samples were taken for testing at the end of the 0h, 1h, 3h, 6h, 9h, 12h, and 24h cycles respectively.

[0091] Pretreatment of water samples: Take 10 ml of supernatant and place it in a 50 ml centrifuge tube. Add 20 ml of ethyl acetate and vortex to mix evenly. Transfer the ethyl acetate layer to another centrifuge tube. Add 20 ml of ethyl acetate to the water sample again and vortex to mix evenly. Combine the two ethyl acetate layers and blow dry them in a 40 ° C water bath with a nitrogen blower. Accurately add 1.0 ml of 10% acetonitrile to dissolve the residue. Filter with a 0.22 μm organic filter membrane for UPLC-MS / MS analysis. The water effluent indicators and nisin concentration are shown in Table 5 and Figure 4 As shown in the figure, the removal rates of COD, TN, TP and nisin were 92.57%, 87.60%, 77.22% and 77.50% at 24 h, respectively, indicating that AGS can resist the toxicity of nisin and may have a good removal effect through adsorption and degradation.

[0092] Table 5 AGS removal effect on nisin

[0093]

[0094] Comparative Example 1

[0095] Preparation of flocculent activated sludge: Flocculent activated sludge was taken from the denitrification filter of a sewage treatment plant in Wuxi, and its MLSS was about 5.0 g / L.

[0096] Add 100 mL of the AGS and flocculent activated sludge adapted in Example 1 into the reactor, control the MLSS in the conical flask to be about 2.5 g / L, and then add the artificially synthesized anti-corrosion cosmetic wastewater to 500 mL. Use an aeration device to aerate it, and the aeration volume is maintained at 0.12 m 3 / h. Two experiments were conducted for each type of sludge: one group added 2.5ug of potassium sorbate to a final concentration of 5ug / L, and the other group added 4ug of nisin to a final concentration of 8ug / L. Four experiments were conducted in total, with the same reaction cycle as the SBR. To ensure better mixing of the sludge and water in each conical flask, magnetic stirring was used at 180rpm. The effluent was tested for water quality and pharmaceuticals for five consecutive days, and the average removal rate of pollutants from the aquaculture wastewater using the two sludges was calculated.

[0097] Table 6 Comparison of pollutant removal effects

[0098]

[0099] Comparative Example 2

[0100] Sulfur autotrophic denitrification sludge: Sulfur autotrophic sludge is taken from the anoxic tank of a sewage treatment plant in Wuxi. After sedimentation, artificially prepared nitrate-containing wastewater is introduced slowly. After about a month, most of the sludge adheres to the sulfur filler and forms a biofilm.

[0101] 100 mL of the AGS and sulfur autotrophic denitrification granular sludge adapted in Example 1 were added to the reactor respectively, and the MLSS in the conical flask was controlled to be about 2.5 g / L. Then, the synthetic anti-corrosion cosmetic wastewater was added to 500 mL, and the AGS was aerated using an aeration device, and the aeration volume was maintained at 0.12 m 3 / h. Sulfur autotrophic granular sludge was stirred. Two experiments were conducted with each sludge type: one group added with 2.5μg of potassium sorbate, and the other with 4μg of nisin. Four experiments were conducted in total, with the same reaction cycle as the SBR. The effluent was tested for water quality and drug removal over five consecutive days, and the average removal rates of pollutants from the aquaculture wastewater using the two sludge types were calculated.

[0102] Table 7 Comparison of pollutant removal effects

[0103]

[0104] Although the present invention has been disclosed above in terms of preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A method for preparing aerobic granular sludge capable of removing potassium sorbate and nisin from wastewater, characterized in that: The steps include: (1) Wastewater and inoculated sludge were added to the SBR reactor; the COD, NH4-N and TP concentrations of the wastewater were 500-600 mg / L, 50-60 mg / L and 10-20 mg / L; the inoculated sludge was A 2 / O process aerobic tank activated sludge; (2) The operating cycle is controlled to be 3.5~4 h, including 3~5 min of water inlet, 210~240 min of aeration time, 2~5 min of static sedimentation, 2~5 min of drainage, 40~60% drainage ratio, 20~30℃ reactor temperature, start the reactor, and maintain the aeration volume at 0.05~0.2 m 3 / h, and completely granulated AGS was obtained after 35-45 days of culture; (3) Reduce the influent COD. Without changing other operating conditions, acclimate the AGS for 40 to 50 days to obtain acclimatized AGS. The influent COD is reduced to 100 to 160 mg / L. (4) Replace the influent with anti-corrosion cosmetic wastewater, without changing other operating conditions, and cultivate for 5 to 9 days to finally obtain aerobic granular sludge that can remove preservatives in the wastewater; The anti-corrosion cosmetic wastewater is prepared by adding 3 to 7 ug / L of potassium sorbate and 6 to 10 ug / L of nisin to the wastewater in step (1).

2. The method according to claim 1, characterized in that In step (1), the height-to-diameter ratio of the SBR reactor is 8-12:

1.

3. The method according to claim 1, wherein In step (1), the wastewater includes sodium acetate, sodium propionate, NH4Cl, K2HPO4, KH2PO4, MgSO4, CaCl2, EDTA and trace element concentrate; wherein the concentration of sodium acetate is 178.8~200mg·L -1 The concentration of sodium propionate is 447~497mg·L -1 The concentration of NH4Cl is 210~230 mg·L -1 The concentration of potassium hydrogen phosphate is 40~44.8 mg·L -1 The concentration of potassium dihydrogen phosphate is 35~35.84 mg·L -1 The concentration of magnesium sulfate is 80~97 mg·L -1 The concentration of calcium chloride is 70~75 mg·L -1 The concentration of EDTA is 7~10 mg·L -1 The concentration of trace element concentrate is 1.44~2.62 μg·L -1 .

4. The method according to claim 3, wherein The trace element concentrate includes ferric chloride, boric acid, copper sulfate, potassium iodide, manganese chloride, zinc chloride, cobalt chloride and sodium molybdate. In artificial simulated synthetic wastewater, the concentration of ferric chloride is 1~1.5μg·L -1 The concentration of boric acid is 0.12~0.15 μg·L -1 The concentration of copper sulfate is 0.02~0.03 μg·L -1 The concentration of potassium iodide is 0.02~0.03 μg·L -1 , the concentration of manganese chloride is 0.10~0.12 μg·L -1 The concentration of zinc chloride is 0.04~0.058 μg·L -1 The concentration of cobalt chloride is 0.10~0.15 μg·L -1 The concentration of sodium molybdate is 0.04~0.06 μg·L -1 .

5. The method according to claim 1, wherein In step (1), the suspended solids concentration of the mixed liquor of the inoculated sludge is 4-6 g / L.

6. Aerobic granular sludge prepared according to the method according to any one of claims 1 to 5.

7. Use of the aerobic granular sludge according to claim 6 in wastewater treatment.

8. A method for treating preservatives in wastewater using the aerobic granular sludge according to claim 6, characterized in that: The steps include: Take aerobic granular sludge and anti-corrosion cosmetic wastewater, mix them, stir and aerate them, and treat them for 20-28 hours; The aeration volume of the aeration is 0.05~0.2 m 3 / h; The anti-corrosion and cosmetic surgery wastewater is wastewater containing potassium sorbate and / or nisin.

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