Method for Simultaneous Reduction of Antibiotic and Thiocyanate Bioinhibition in Erythromycin Wastewater

Abstract

The present invention discloses a method for simultaneously reducing the biological inhibition of antibiotics and thiocyanate in erythromycin wastewater, and relates to the technical field of industrial wastewater treatment. The specific treatment method includes: by regulating the water quality characteristics of the wastewater, adding a selective reaction reagent, and regulating the reaction temperature, time, and stirring rate, the simultaneous microbial toxicity reduction of antibiotics and thiocyanate in the erythromycin wastewater is achieved. The method of the present invention has a stable reaction process, easy-to-regulate process conditions, a short time consumption, a strong selectivity in the removal process, and no need to regulate or remove other substances in the wastewater; it effectively solves the problem that erythromycin wastewater has a strong inhibitory effect on anaerobic biological processes due to the presence of high concentrations of erythromycin residual titers and thiocyanate ions, making it difficult to enter the anaerobic biological treatment process for efficient organic matter removal, and has good industrial application prospects.

Description

Technical Field

[0001] The invention relates to the technical field of industrial wastewater treatment, in particular to a method for synchronously reducing antibiotic and thiocyanate bioinhibition in erythromycin wastewater. Background Art

[0002] Erythromycin wastewater is a high-concentration organic wastewater characterized by high pollution load, high toxicity, and strong antibacterial properties. It primarily originates from waste fermentation broth or synthetic wastewater after raw material extraction during erythromycin production. Because large amounts of sodium thiocyanate are added during the production process to promote the concentration and crystallization of erythromycin to produce the product, the wastewater generated in this process has high concentrations of erythromycin residual potency and thiocyanate, along with significant amounts of fermentation medium components or organic raw materials. The wastewater also contains large amounts of water, high COD, and high levels of suspended solids. Long-term operational experience both domestically and internationally demonstrates that biologically based wastewater treatment technologies, compared to physicochemical technologies, offer advantages such as lower chemical reagent dosage, lower operating costs, and reduced risk of secondary pollution, making them the preferred choice for treating antibiotic pharmaceutical wastewater.

[0003] However, high concentrations of residual erythromycin and thiocyanate in erythromycin wastewater have a strong inhibitory effect on microbial activity and are toxic, limiting the effectiveness of biological treatment and making it difficult to meet effluent quality requirements. Furthermore, the presence of high residual erythromycin can also lead to the emergence of a large number of drug-resistant bacteria and resistance genes during the biological treatment process. These resistant bacteria, resistance genes, and undegraded antibiotics enter the environment with treated wastewater and residual sludge, potentially posing a significant safety hazard. Therefore, the efficient and selective removal of erythromycin residuals and thiocyanate in advance is key to the efficient and low-cost biological treatment of this type of wastewater.

[0004] Currently, hydrolysis is commonly used to selectively destroy the pharmacological functional groups of antibiotics, but it is difficult to simultaneously remove thiocyanate during the antibiotic removal process. Treatment methods for single thiocyanate include coagulation, ion exchange, adsorption, and oxidation. These methods have poor selectivity for antibiotic removal, low treatment efficiency, and high treatment costs. Therefore, it is necessary to develop a simultaneous pretreatment technology that can achieve the simultaneous and efficient removal of erythromycin titer and thiocyanate under relatively simple and mild conditions, and relieve its inhibitory effects on anaerobic biological processes. Summary of the Invention

[0005] The object of the present invention is to provide a method for simultaneously reducing antibiotics and thiocyanate bioinhibition in erythromycin wastewater, so as to solve the problem that the erythromycin residual potency and the microbial toxicity of thiocyanate in existing erythromycin wastewater are difficult to be effectively and simultaneously reduced.

[0006] In order to solve the above technical problems, the present invention specifically provides the following technical solutions:

[0007] The present invention discloses a method for treating erythromycin wastewater, comprising:

[0008] First, the pH of the erythromycin wastewater is adjusted. Then, a selective reaction reagent is added to react and produce treated wastewater. The selective reaction reagent includes an oxidant and a catalytic promoter, with the ratio of oxidant to erythromycin wastewater being 2-15g:1L. The mechanism of action of the selective reaction reagent is closely related to the structure and functional groups of the pollutant molecules. Based on the electron-absorbing properties, molecular size, structure, and functional group properties of thiocyanate and erythromycin, a matching oxidant is selected, or a catalytic promoter is coupled with the oxidant to achieve precise control of the active sites, thereby improving the degradation efficiency and stability of thiocyanate and erythromycin in complex wastewater.

[0009] Preferably, the COD in the erythromycin wastewater is 10,000-100,000 mg / L, the erythromycin residual titer is 10-1,000 mg / L, and the thiocyanate ion is 1,000-9,000 mg / L.

[0010] Preferably, the oxidizing agent is at least one of hydrogen peroxide, calcium peroxide, perchlorate, ferrate, persulfate, percarbonate, peracetic acid and vanadium oxychloride.

[0011] Preferably, the catalyst promoter is at least one of metal oxides, bicarbonates, metal salts, ion exchange resins, zeolite molecular sieves and mesoporous materials.

[0012] Preferably, the dosage ratio of the catalyst aid to erythromycin wastewater is 2-100 g:1 L.

[0013] Preferably, the ion exchange resin is at least one of a strongly acidic perfluorosulfonic acid cation exchange resin, a macroporous strongly basic styrene-based anion exchange resin, and a strongly basic modified anion resin. The strongly basic modified anion resin is prepared from chloromethyl polystyrene gel resin, 3,3-diaminoacrylonitrile, and 1,4-dichloromethylnaphthalene. Strongly basic modified anion resins have multiple functional groups and excellent stability. Using strongly basic modified anion resins as catalyst aids can effectively promote the degradation of erythromycin and thiocyanate in erythromycin wastewater, thereby improving the removal rate of erythromycin residual potency, thiocyanate removal, and anaerobic methanogenesis activity.

[0014] Preferably, the pH is 3-11.

[0015] Preferably, the reagents used to adjust the pH are sodium hydroxide solution and hydrochloric acid solution. The sodium hydroxide solution consists of sodium hydroxide and water, and the dosage ratio of sodium hydroxide to water is 0.4-40g:1L. The hydrochloric acid solution consists of hydrochloric acid and water, and the dosage ratio of hydrochloric acid to water is 3-37g:1L.

[0016] Preferably, the reaction temperature is 50-100° C., and the reaction time is 5-480 min.

[0017] Preferably, the reaction is carried out using at least one of mechanical stirring and magnetic stirring at a rotation speed of 50-400 rpm.

[0018] The present invention discloses a method for treating erythromycin wastewater, comprising:

[0019] First, the pH of erythromycin wastewater is adjusted to 3-11, and then a selective reaction reagent is added, and the reaction is carried out at 50-100° C. and 50-400 rpm for 5-480 minutes to obtain treated wastewater.

[0020] Preferably, the COD in the erythromycin wastewater is 10,000-100,000 mg / L, the erythromycin residual titer is 10-1,000 mg / L, and the thiocyanate ion is 1,000-9,000 mg / L.

[0021] Preferably, the erythromycin wastewater further contains complex salt ions of sulfate, chloride and nitrate.

[0022] Preferably, the erythromycin wastewater is at least one of erythromycin fermentation broth, erythromycin crystallization extraction mother liquor and erythromycin equipment cleaning wastewater.

[0023] Preferably, the selective reaction reagents include an oxidizing agent and a catalytic co-agent.

[0024] More preferably, the oxidant is at least one of hydrogen peroxide, calcium peroxide, perchlorate, ferrate, persulfate, percarbonate, peracetic acid and vanadium trichloride, and the oxidant is capable of generating free radicals and free radical derivatives, including hydroxyl radicals, sulfate radicals, superoxide anion radicals, singlet oxygen and hydrogen peroxide.

[0025] More preferably, the dosage ratio of the oxidant to erythromycin wastewater is 2-15 g:1 L.

[0026] More preferably, the catalyst promoter is at least one of metal oxides, bicarbonates, metal salts, ion exchange resins, zeolite molecular sieves, and mesoporous materials. The catalyst promoter can provide active sites or accelerate electron transport and transfer.

[0027] Preferably, the dosage ratio of the catalyst aid to erythromycin wastewater is 2-100 g:1 L.

[0028] More preferably, the metal oxide is at least one of bismuth oxyiodide, iron oxychloride, aluminum oxide, zinc oxide, an aluminum oxide-iron oxide composite, and a calcium oxide-zirconium oxide composite.

[0029] More preferably, the metal salt is at least one of aluminum phosphate, iron sulfate, and potassium carbonate-γ-alumina.

[0030] More preferably, the ion exchange resin is at least one of a strongly acidic perfluorosulfonic acid cation exchange resin, a macroporous strongly basic styrene anion exchange resin and a strongly basic modified anion resin, and the strongly basic modified anion resin is prepared from chloromethyl polystyrene gel resin, 3,3-diaminoacrylonitrile and 1,4-dichloromethylnaphthalene.

[0031] Preferably, the reagents used to adjust the pH are sodium hydroxide solution and hydrochloric acid solution. The sodium hydroxide solution consists of sodium hydroxide and water, and the dosage ratio of sodium hydroxide to water is 0.4-40g:1L. The hydrochloric acid solution consists of hydrochloric acid and water, and the dosage ratio of hydrochloric acid to water is 3-37g:1L.

[0032] Preferably, the reaction adopts at least one of mechanical stirring and magnetic stirring, and the electron transfer is optimized by stirring and temperature control, thereby promoting the destruction of the erythromycin pharmacodynamic functional group and the thiocyanate structure and improving the treatment efficiency.

[0033] The present invention discloses a method for preparing a strongly basic modified anionic resin, which is specifically:

[0034] S1: Add N,N-dimethylformamide to chloromethyl polystyrene gel resin for swelling, then add 3,3-diaminoacrylonitrile, react at 50-70°C for 15-25h, and filter to obtain the modified resin after the reaction is completed.

[0035] S2: Add N,N-dimethylformamide to the modified resin for swelling, then add 1,4-dichloromethylnaphthalene, react at 50-70°C for 5-15 hours, and filter and wash after the reaction to obtain a strongly alkaline modified anion resin.

[0036] Preferably, the amount ratio of the chloromethyl polystyrene gel resin and the added N,N-dimethylformamide in S1 is 0.05-0.2 g: 1 ml.

[0037] Preferably, the mass ratio of the chloromethyl polystyrene gel resin to 3,3-diaminoacrylonitrile in S1 is 1:0.5-1.

[0038] Preferably, the solvent used for washing in S1 includes water, hydrochloric acid solution and sodium hydroxide solution. The product is first washed with water until neutral, and then washed with hydrochloric acid solution, water and sodium hydroxide solution in sequence.

[0039] More preferably, the hydrochloric acid solution consists of hydrochloric acid and water, and the usage ratio of hydrochloric acid to water is 30-40g:1L.

[0040] More preferably, the sodium hydroxide solution consists of sodium hydroxide and water, and the dosage ratio of sodium hydroxide to water is 30-50g:1L.

[0041] Preferably, the ratio of the modified resin to the added N,N-dimethylformamide in S2 is 0.05-0.2 g: 1 ml.

[0042] Preferably, the mass ratio of the modified resin to 1,4-dichloromethylnaphthalene in S2 is 1:1.2-2.

[0043] Preferably, the solvent used for washing in S2 includes ethanol solution, ethanol and water, and washing is carried out with ethanol solution, ethanol and water in sequence.

[0044] More preferably, the ethanol solution consists of ethanol and triethylamine, and the mass ratio of ethanol to triethylamine is 1:0.05-0.15.

[0045] More preferably, the present invention uses modified chitosan in addition to a strongly basic modified anionic resin during the treatment of erythromycin wastewater. The use of modified chitosan can further promote the degradation of erythromycin wastewater by oxides, and can synergistically promote flocculation, reduce the amount of suspended matter, and thus improve the erythromycin residual titer removal rate, thiocyanate removal rate, and anaerobic methanogenesis activity.

[0046] Preferably, the usage ratio of modified chitosan to erythromycin wastewater is 0.04-0.25 g:1 L.

[0047] The present invention discloses a method for preparing modified chitosan, which specifically comprises:

[0048] Chitosan is dissolved in a hydrochloric acid solution and the pH is adjusted to 4-6 to obtain a chitosan solution. 4-Dimethylaminopyridine and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride are dissolved in N,N-dimethylformamide to obtain a mixed solution. The mixed solution is then added to the chitosan solution and reacted at 20-30°C for 1-3 hours. A 3-sulfopropionic acid solution and a 5-phenylpentane-2,4-dicarboxylic acid solution are then added dropwise and reacted at 20-30°C for 3-5 hours. After the reaction is complete, acetone is added and the precipitate is separated by filtration. The precipitate is washed and dried to obtain modified chitosan.

[0049] Preferably, the hydrochloric acid solution consists of hydrochloric acid and water, the usage ratio of hydrochloric acid to water is 8-12 g:1 L, and the usage ratio of chitosan to hydrochloric acid solution is 0.005-0.015 g:1 ml.

[0050] Preferably, the usage ratio of 4-dimethylaminopyridine to N,N-dimethylformamide is 0.006-0.009 g:1 ml.

[0051] Preferably, the ratio of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride to N,N-dimethylformamide is 0.03-0.1 g:1 ml.

[0052] Preferably, the volume ratio of the chitosan solution to the mixed solution is 1:0.1-0.5. Preferably, the 3-sulfopropionic acid solution is composed of 3-sulfopropionic acid and water, and the usage ratio of 3-sulfopropionic acid to water is 0.002-0.01 g:1 ml.

[0053] Preferably, the volume ratio of the chitosan solution to the 3-sulfopropionic acid solution is 1:0.35-0.7.

[0054] Preferably, the 5-phenylpentane-2,4-dicarboxylic acid solution consists of 5-phenylpentane-2,4-dicarboxylic acid and N,N-dimethylformamide, and the usage ratio of 5-phenylpentane-2,4-dicarboxylic acid to N,N-dimethylformamide is 0.002-0.01 g:1 ml.

[0055] Preferably, the volume ratio of the chitosan solution to the 5-phenylpentane-2,4-dicarboxylic acid solution is 1:0.35-0.7.

[0056] Compared with the prior art, the present invention has the following beneficial effects:

[0057] The present invention proposes a method for simultaneously reducing the bioinhibition of antibiotics and thiocyanate in erythromycin wastewater. By regulating the wastewater quality characteristics, adding selective reaction reagents, and controlling the reaction temperature, time, and stirring rate, the simultaneous microbial toxicity reduction of antibiotics and thiocyanate in erythromycin wastewater is achieved. The present invention has high reaction efficiency, simple reaction conditions, strong selectivity, and shortened treatment process. It can also achieve a removal rate of greater than 95% for the residual erythromycin titer and thiocyanate in erythromycin wastewater. Anaerobic methanogenesis activity monitoring shows that the anaerobic methanogenesis activity of the treated erythromycin wastewater is 50%-600% higher than that of the untreated wastewater, and the relative abundance of drug-resistant genes in the treated effluent is less than 50 copies / cell. The wastewater treated using this method and technology can be further treated through subsequent biochemical treatment processes to ultimately meet wastewater discharge standards. The subsequent biochemical treatment process can be hydrolysis and acidification, anaerobic process, aerobic process, or a combination thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other implementation drawings based on the provided drawings without inventive effort.

[0059] Figure 1 This is a process flow chart for the simultaneous reduction of antibiotic and thiocyanate bioinhibition in erythromycin wastewater;

[0060] Figure 2This is the cumulative anaerobic methane production graph;

[0061] Figure 3 This is the result of measuring the changes in wastewater during the reaction process. DETAILED DESCRIPTION

[0062] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0063] The following first describes the concepts involved in this application with reference to the accompanying drawings. It should be noted that the following description of each concept is intended only to make the content of this application easier to understand and does not limit the scope of protection of this application. At the same time, the embodiments and features in the embodiments of this application can be combined with each other unless there is a conflict. The following detailed description of this application will be made with reference to the accompanying drawings and in conjunction with the embodiments.

[0064] Example 1:

[0065] Treatment of erythromycin wastewater: Hydrochloric acid solution is added to the erythromycin wastewater to adjust the pH to 5, and then hydrogen peroxide is added. The reaction is carried out at 95°C and 300 rpm for 360 minutes to obtain the treated wastewater. The erythromycin wastewater is erythromycin thiocyanate fermentation waste liquor produced in a pharmaceutical production process. The erythromycin residual titer in the erythromycin wastewater is 60 mg / L, the amount of thiocyanate in the erythromycin wastewater is 2000 mg / L, the COD in the erythromycin wastewater is 70,000 mg / L, the amount of sulfate ions in the erythromycin wastewater is 4000 mg / L, and the amount of suspended solids in the erythromycin wastewater is 1500 mg / L. The hydrochloric acid solution is composed of hydrochloric acid and water, with a hydrochloric acid:water ratio of 30 g:1 L. The amount of hydrogen peroxide to erythromycin wastewater is 5.18 g:1 L.

[0066] Example 2:

[0067] Treatment of erythromycin wastewater: Calcium peroxide was added to the erythromycin wastewater, followed by ultrasonic reaction at 60°C for 360 minutes at 400W ultrasonic power to obtain the treated wastewater. The erythromycin wastewater was erythromycin thiocyanate fermentation waste liquor produced in a pharmaceutical production process. The pH of the erythromycin wastewater was 6, the erythromycin residual titer was 100mg / L, the thiocyanate content was 6000mg / L, the COD content was 50000mg / L, the sulfate content was 150mg / L, and the suspended solids content was 1300mg / L. The ratio of calcium peroxide to erythromycin wastewater was 3.604g:1L.

[0068] Example 3:

[0069] Preparation of modified resin: N,N-dimethylformamide was added to chloromethyl polystyrene gel resin to swell it, followed by the addition of 3,3-diaminoacrylonitrile. The mixture was reacted at 60°C for 20 hours. After completion of the reaction, the mixture was filtered and washed with water until neutral. The modified resin was then washed sequentially with hydrochloric acid solution, water, and sodium hydroxide solution to obtain the modified resin. The mass ratio of chloromethyl polystyrene gel resin to N,N-dimethylformamide was 0.1 g:1 ml, the mass ratio of chloromethyl polystyrene gel resin to 3,3-diaminoacrylonitrile was 1:0.64, the hydrochloric acid solution was composed of hydrochloric acid and water in a ratio of 36.5 g:1 L, and the sodium hydroxide solution was composed of sodium hydroxide and water in a ratio of 40 g:1 L.

[0070] Preparation of a strongly basic modified anion resin: N,N-dimethylformamide was added to the modified resin to swell it, followed by the addition of 1,4-dichloromethylnaphthalene. The mixture was reacted at 60°C for 10 hours. After completion of the reaction, the resin was filtered and washed sequentially with an ethanol solution, ethanol, and water to obtain a strongly basic modified anion resin. The modified resin and N,N-dimethylformamide were used in a ratio of 0.1 g:1 ml, and the mass ratio of the modified resin to 1,4-dichloromethylnaphthalene was 1:1.74. The ethanol solution consisted of ethanol and triethylamine in a mass ratio of 1:0.1.

[0071] Treatment of erythromycin wastewater: Calcium peroxide and a strongly alkaline modified anion resin were added to the erythromycin wastewater, followed by ultrasonic reaction at 400W power and 60°C for 360 minutes to obtain the treated wastewater. The erythromycin wastewater was erythromycin thiocyanate fermentation waste liquor produced in a pharmaceutical production process. The pH of the erythromycin wastewater was 6, the erythromycin residual titer was 100mg / L, the thiocyanate content was 6000mg / L, the COD content was 50000mg / L, the sulfate content was 150mg / L, and the suspended solids content was 1300mg / L. The dosage ratio of calcium peroxide to erythromycin wastewater was 3.604g:1L, and the dosage ratio of the strongly alkaline modified anion resin to erythromycin wastewater was 40g:1L.

[0072] Example 4:

[0073] The preparation of the strongly basic modified anionic resin is the same as in Example 3.

[0074] Treatment of erythromycin wastewater: The treatment of erythromycin wastewater in this embodiment is compared with that in Example 3, except that the usage ratio of the strongly basic modified anion resin to erythromycin wastewater is 60 g:1 L, and other conditions and parameters are the same as in Example 3.

[0075] Example 5:

[0076] The preparation of the strongly basic modified anionic resin is the same as in Example 3.

[0077] Preparation of modified chitosan: Chitosan was dissolved in hydrochloric acid and the pH was adjusted to 5 to obtain a chitosan solution. 4-Dimethylaminopyridine and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride were dissolved in N,N-dimethylformamide to obtain a mixed solution. The mixed solution was then added to the chitosan solution and reacted at 25°C for 2 hours. A solution of 3-sulfopropionic acid and a solution of 5-phenylpentane-2,4-dicarboxylic acid were then added dropwise and reacted at 25°C for 4 hours. After the reaction, acetone was added and the precipitate was separated by filtration. The precipitate was washed and dried to obtain the modified chitosan. The hydrochloric acid solution is composed of hydrochloric acid and water, the amount ratio of hydrochloric acid to water is 10g:1L, the amount ratio of chitosan to hydrochloric acid solution is 0.01g:1ml, the amount ratio of 4-dimethylaminopyridine to N,N-dimethylformamide is 0.0075g:1ml, the amount ratio of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride to N,N-dimethylformamide is 0.065g:1ml, the volume ratio of chitosan solution to mixed solution is 1:0.2, the 3-sulfopropionic acid solution is composed of 3-sulfopropionic acid The solution is composed of propionic acid and water, the amount ratio of 3-sulfopropionic acid and water is 0.005g:1ml, the volume ratio of chitosan solution to 3-sulfopropionic acid solution is 1:0.5, the 5-phenylpentane-2,4-dicarboxylic acid solution is composed of 5-phenylpentane-2,4-dicarboxylic acid and N,N-dimethylformamide, the amount ratio of 5-phenylpentane-2,4-dicarboxylic acid and N,N-dimethylformamide is 0.003g:1ml, and the volume ratio of chitosan solution to 5-phenylpentane-2,4-dicarboxylic acid solution is 1:0.5.

[0078] Treatment of erythromycin wastewater: Calcium peroxide and strongly alkaline modified anion resin were added to the erythromycin wastewater, and then ultrasonically reacted at 60°C for 360 minutes under an ultrasonic power of 400W, and then modified chitosan was added and the reaction was continued for 30 minutes to obtain treated wastewater. The erythromycin wastewater is the erythromycin thiocyanate fermentation waste liquor produced by a production process in a pharmaceutical industry. The pH of the erythromycin wastewater is 6, the residual titer of erythromycin in the erythromycin wastewater is 100 mg / L, the amount of thiocyanate in the erythromycin wastewater is 6000 mg / L, the COD of the erythromycin wastewater is 50000 mg / L, the amount of sulfate ions in the erythromycin wastewater is 150 mg / L, the amount of suspended matter in the erythromycin wastewater is 1300 mg / L, the dosage ratio of calcium peroxide to erythromycin wastewater is 3.604 g:1L, the dosage ratio of strong alkaline modified anion resin to erythromycin wastewater is 40 g:1L, and the dosage ratio of modified chitosan to erythromycin wastewater is 0.08 g:1L.

[0079] Example 6:

[0080] The preparation of the strongly basic modified anionic resin is the same as in Example 3.

[0081] The preparation of modified chitosan is the same as that in Example 5.

[0082] Treatment of erythromycin wastewater: The treatment of erythromycin wastewater in this example is compared with that in Example 5, except that the usage ratio of modified chitosan to erythromycin wastewater is 0.2 g:1 L. Other conditions and parameters are the same as those in Example 5.

[0083] Comparative Example 1:

[0084] The preparation of the strongly basic modified anionic resin is the same as in Example 3.

[0085] Treatment of erythromycin wastewater: The treatment of erythromycin wastewater in this example is compared with that in Example 3, except that the usage ratio of the strongly basic modified anion resin to erythromycin wastewater is 1 g:1 L, and other conditions and parameters are the same as in Example 3.

[0086] Experimental Example 1:

[0087] The erythromycin removal rate in the wastewater was determined. UPLC / MS / MS was used to detect changes in erythromycin concentration in the wastewater. Turbidimetry was used according to the Pharmacopoeia of the People's Republic of China (2010 edition) to determine changes in the potency of residual organisms in the erythromycin wastewater. Erythromycin removal rate (%) = (erythromycin potency in initial erythromycin wastewater - erythromycin potency in treated wastewater) / erythromycin potency in initial erythromycin wastewater × 100%. The wastewater included the initial erythromycin wastewater and the treated wastewater obtained in Examples 1-7 and Comparative Example 1.

[0088] Table 1 Determination results of erythromycin titer removal rate

[0089]

[0090] The results are shown in Table 1. The treatments of Example 1 and Example 2 have a better effect on the removal of erythromycin titer in erythromycin wastewater. Compared with Example 3, Example 2 shows that the use of the strongly basic modified anionic resin can improve the erythromycin titer removal rate of erythromycin wastewater. Compared with Example 4, Example 3 shows that the erythromycin titer removal rate of erythromycin wastewater can be further improved by increasing the usage of the strongly basic modified anionic resin within a certain range. Compared with Example 5, Example 3 shows that the erythromycin titer removal rate of erythromycin wastewater can be improved by using modified chitosan on the basis of using the strongly basic modified anionic resin. Compared with Example 6, Example 5 shows that the erythromycin titer removal rate of erythromycin wastewater can be improved by increasing the usage of the modified chitosan within a certain range. Compared with Comparative Example 1, Example 3 shows that the usage of the strongly basic modified anionic resin needs to be within an appropriate range. Too low an amount has no obvious effect on improving the erythromycin titer removal rate of erythromycin wastewater.

[0091] Experimental Example 2:

[0092] The thiocyanate removal rate in the wastewater was determined by spectrophotometry, measuring the change in thiocyanate concentration in the wastewater. Thiocyanate removal rate (%) = (thiocyanate concentration in initial erythromycin wastewater - thiocyanate concentration in treated wastewater) / initial thiocyanate concentration in erythromycin wastewater × 100%. The wastewater included the initial erythromycin wastewater and the treated wastewater obtained in Examples 1-7 and Comparative Example 1.

[0093] Table 2 Determination results of thiocyanate removal rate

[0094]

[0095] The results are shown in Table 2. The treatment of erythromycin wastewater by Example 1 and Example 2 has a better effect on the removal of thiocyanate in erythromycin wastewater; compared with Example 3, Example 2 shows that the use of the strongly basic modified anion resin can further improve the thiocyanate removal rate of erythromycin wastewater to a higher value; compared with Comparative Example 1, Example 3 shows that the usage amount of the strongly basic modified anion resin needs to be within an appropriate range. If it is too low, there is no obvious effect on improving the thiocyanate removal rate of erythromycin wastewater.

[0096] Experimental Example 3:

[0097] The wastewater was further treated using anaerobic sludge, and the anaerobic methanogenesis activity was measured to evaluate changes in the biological inhibition of the wastewater. The anaerobic sludge was municipal anaerobic digestion sludge, which was used as inoculum sludge. The inoculum sludge concentration was set to 6000 mgVSS / L. The wastewater was diluted to a COD of 3000 mg / L. The inoculum sludge was mixed with the wastewater and cultured under mesophilic anaerobic conditions for 15 days at a culture temperature of 35°C. The cumulative methane production during the process was detected. The wastewater included the initial erythromycin wastewater and the treated wastewater obtained from Examples 1-7 and Comparative Example 1.

[0098] Table 3 Measurement results of cumulative methane production

[0099]

[0100] The cumulative methane production results of the initial erythromycin wastewater and the treated wastewater obtained in Example 1 are shown in Tables 3 and Figure 2As shown, the cumulative methane production of the treated wastewater obtained in Example 1 is increased by 634% compared with the initial erythromycin wastewater. The results of the cumulative methane production of the treated wastewater obtained in Examples 2-6 and Comparative Example 1 are shown in Table 3. Compared with Example 3, Example 2 shows that the use of the strongly basic modified anion resin can increase the cumulative methane production of the treated wastewater, that is, improve the anaerobic methanogenesis activity; compared with Example 4, Example 3 shows that the use of the strongly basic modified anion resin increases within a certain range, and the cumulative methane production of the treated wastewater can also be further increased; compared with Example 5, Example 3 shows that on the basis of using the strongly basic modified anion resin, the use of modified chitosan to treat erythromycin wastewater can promote a further increase in the cumulative methane production; compared with Example 6, Example 5 shows that the use of modified chitosan within a certain range can increase the cumulative methane production of the treated wastewater; compared with Comparative Example 1, Example 3 shows that the use of the strongly basic modified anion resin needs to be within an appropriate range. Too low an amount has no obvious promoting effect on the increase in the cumulative methane production of the treated wastewater.

[0101] Experimental Example 4:

[0102] The changes in the wastewater during the reaction were monitored and measured. In the treatment process of erythromycin wastewater in Example 1, after the addition of hydrogen peroxide and the reaction, samples were taken at different times to measure the erythromycin residual potency, thiocyanate concentration, erythromycin potency removal rate, and thiocyanate removal rate. The measurement method was the same as that of Experimental Examples 1 and 2.

[0103] Table 4 Measurement results of wastewater changes during the reaction process

[0104]

[0105] The results are shown in Table 4 and Figure 3 As shown, Figure 3 C represents the erythromycin residual titer and thiocyanate concentration measured at different times, and C0 represents the initial erythromycin residual titer and thiocyanate concentration. As reaction time increases, both the erythromycin residual titer and thiocyanate concentration decrease, effectively improving the erythromycin titer and thiocyanate removal rates.

[0106] The embodiments and / or implementation methods described above are only used to illustrate the preferred embodiments and / or implementation methods for realizing the technology of the present invention, and do not impose any form of limitation on the implementation methods of the technology of the present invention. Any person skilled in the art may make slight changes or modifications to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as technologies or embodiments that are essentially the same as the present invention.

[0107] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. The above is only the preferred implementation method of this application. It should be pointed out that due to the limitations of textual expression, there are objectively infinite specific structures. For ordinary technicians in this technical field, without departing from the principles of this application, they can also make several improvements, modifications or changes, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the scope of protection of this application.

Claims

1. A method for treating erythromycin wastewater, comprising: First, the pH of erythromycin wastewater is adjusted, and then a selective reaction reagent is added to react to obtain treated wastewater; the selective reaction reagent includes an oxidant and a catalytic aid, and the dosage ratio of the oxidant to the erythromycin wastewater is 2-15g:1L; the dosage ratio of the catalytic aid to the erythromycin wastewater is 2-100g:1L; The oxidant is calcium peroxide, and the catalyst aid is ion exchange resin; The ion exchange resin is a strongly basic modified anion resin, which is prepared from chloromethyl polystyrene gel resin, 3,3-diaminoacrylonitrile and 1,4-dichloromethylnaphthalene, specifically: S1: Add N,N-dimethylformamide to chloromethyl polystyrene gel resin to swell it, then add 3,3-diaminoacrylonitrile, react at 50-70°C for 15-25 hours, and filter to obtain the modified resin after the reaction is completed; S2: Add N,N-dimethylformamide to the modified resin for swelling, then add 1,4-dichloromethylnaphthalene, react at 50-70°C for 5-15h, filter and wash after the reaction to obtain a strongly alkaline modified anion resin; the amount ratio of chloromethyl polystyrene gel resin to the added N,N-dimethylformamide is 0.05-0.2g:1ml, and the mass ratio of chloromethyl polystyrene gel resin to 3,3-diaminoacrylonitrile is 1:0.5-1; the amount ratio of the modified resin to the added N,N-dimethylformamide is 0.05-0.2g:1ml, and the mass ratio of the modified resin to 1,4-dichloromethylnaphthalene is 1:1.2-2.

2. a treatment method for erythromycin wastewater according to claim 1, is characterized in that: The COD in the erythromycin wastewater is 10,000-100,000 mg / L, the erythromycin residual titer is 10-1,000 mg / L, and the thiocyanate ion is 1,000-9,000 mg / L.

3. a treatment method for erythromycin wastewater according to claim 1, is characterized in that: The pH is 3-11.

4. a method for treating erythromycin wastewater according to claim 1, is characterized in that: The reagents used for adjusting the pH are sodium hydroxide solution and hydrochloric acid solution. The sodium hydroxide solution consists of sodium hydroxide and water, and the usage ratio of sodium hydroxide to water is 0.4-40g:1L. The hydrochloric acid solution consists of hydrochloric acid and water, and the usage ratio of hydrochloric acid to water is 3-37g:1L.

5. a treatment method for erythromycin wastewater according to claim 1, is characterized in that: The reaction temperature of the erythromycin wastewater and the selective reaction reagent is 50-100° C., and the reaction time is 5-480 min.

6. a treatment method for erythromycin wastewater according to claim 1, is characterized in that: The reaction between the erythromycin wastewater and the selective reaction reagent adopts at least one of mechanical stirring and magnetic stirring at a rotation speed of 50-400 rpm.

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