催化臭氧化技术去除典型的抗生素及抗性基因研究

发布时间：2018-04-28 04:28

本文选题：给水厂 + 抗生素　；参考：《山东建筑大学》2017年硕士论文

【摘要】：本论文检测分析了某市内某深度处理给水厂中5种典型抗生素红霉素(ETM)、磺胺甲恶唑(SMX)、磺胺嘧啶(SD)、土霉素(TC)和四环素(OTC)的含量,并对抗生素在该水厂生产性工艺流程中的沿程变化和去除规律进行了研究;长期过量的抗生素持续不断的排入环境中,造成很高的抗生素选择压力,诱导微生物产生抗生素抗性基因(ARGs)。大量研究表明ARGs广泛存在于土壤,地表水甚至是地下水中。为保障饮水安全,研究选用4种常见的抗生素抗性基因sul?、sulⅡ、tet A和tet G为目标基因,通过实时荧光定量PCR方法对该水厂基因浓度进行了绝对定量,分析了该水厂中4种抗性基因的分布情况;以磺胺嘧啶为研究对象,考察了不同的催化臭氧氧化技术对抗生素的去除效果,在此基础上通过考察磺胺嘧啶在降解过程中的可生物降解性和毒理性的变化对不同的催化臭氧氧化技术进行评价。研究结果表明,在三次样品采集中该水厂进水均含有5种抗生素,其中磺胺甲恶唑的浓度最高为59.40 ng/L,红霉素的浓度最低为0.87 ng/L;5种抗生素含量沿水厂工艺流程均呈现出逐渐降低的趋势。在水厂出水中抗生素的含量大大降低,有2种抗生素未检出,其余3种抗生素浓度均在7 ng/L以下。水厂整体工艺对目标抗生素具有良好的去除效果,总去除率达89.9%,其中臭氧氧化和生物活性炭处理单元对抗生素的去除效果明显,总绝对去除率分别为71.2%和13.1%;高密度沉淀单元、砂滤单元和加氯消毒单元对抗生素的去除贡献不大,总去除率均在5%以下。臭氧氧化和生物活性炭单元为水厂的深度处理单元,高密度沉淀、砂滤和加氯消毒单元为水厂的传统处理单元,由研究结果可知,相比传统处理工艺,深度处理工艺对抗生素的去除效果更好。对该水厂进水及各处理单元出水中细菌进行DNA提取及荧光定量PCR检测。研究表明,该水厂进水中均含有4种抗生素抗性基因,sul?、sulⅡ、tet A和tet G的浓度分别为2.54×10~3copies/ml、1.36×10~3 copies/ml、1.47×102 copies/ml和0.064×102 copies/ml。4种抗性基因的浓度沿该水厂工艺流程呈现出先降低后升高再降低的趋势。其中,臭氧氧化单元出水和加氯消毒单元出水中ARGs的含量最低,未检测出ARGs;生物活性炭单元出水中ARGs的含量升高,4种ARGs的浓度分别为1.12×10~3 copies/ml、0.18×102 copies/ml、0.05×102 copies/ml和0.14×102copies/ml。不同的催化臭氧氧化技术对抗生素的去除作用和矿化程度不同。以磺胺嘧啶为研究对象,比较了单独O_3氧化、O_3/H_2O_2、O_3/UV及O_3/UV/H_2O_2对磺胺嘧啶的去除效果。结果表明,p H在中性条件下,4种氧化技术对磺胺嘧啶均有良好的去除效果,在臭氧投加量为10mg/L时,O_3/UV/H_2O_2几乎能够完全去除磺胺嘧啶,其余三种技术对磺胺嘧啶的去除率分别为82.5%、91.7%和98.6%;在臭氧投加量为12 mg/L时,O_3/UV也能完全去除磺胺嘧啶。因此,O_3/UV/H_2O_2对磺胺嘧啶的去除效果优于O_3/UV优于O_3/H_2O_2优于单独O_3氧化。单独O_3氧化对磺胺嘧啶的矿化程度较低,在臭氧投加量为12 mg/L时,TOC的去除率为19.6%,其他三种技术对TOC的去除率分别为34.60%、46.54%和55.87%。由此可知,催化臭氧化比单独O_3对磺胺嘧啶的矿化程度更高。为了进一步对4种催化臭氧氧化技术进行分析对比,分别检测了氧化前后磺胺嘧啶溶液的可生物降解性和生物急性毒性的变化。结果表明,随着臭氧投加量的增加,溶液的可生物降解性逐渐增大。不同的催化臭氧氧化技术对磺胺嘧啶溶液的可生物降解性影响不同,当臭氧投加量从0 mg/L增加到12 mg/L时,经单独O_3氧化后,溶液中BDOC的含量从0.107mg/L增加到0.875 mg/L;经O_3/H_2O_2、O_3/UV和O_3/UV/H_2O_2处理后,溶液中BDOC的浓度分别从0.107 mg/L增加到1.007 mg/L、1.046 mg/L和1.29 mg/L。由结果可知,催化臭氧氧化技术氧化磺胺嘧啶后溶液的可生物降解性更强。向氧化前后的磺胺嘧啶溶液中分别加入发光细菌菌液,静置15 min后测定发光细菌的发光强度,从而得出溶液对发光细菌的抑制率。氧化前不同浓度的磺胺嘧啶溶液对发光细菌的抑制表现出良好的线性关系,磺胺嘧啶的EC20为562.7 mg/L,EC50为1235.35 mg/L。随着氧化时间的延长,溶液对发光细菌的抑制率逐渐升高,当氧化时间延长至140 min时,四种技术氧化磺胺嘧啶后对发光细菌的发光抑制率分别达到95.55%、96.34%、91.6%和99.85%。
[Abstract]:In this paper, the contents of 5 typical antibiotics, erythromycin (ETM), sulfonamoxazole (SMX), sulfadiazine (SD), oxytetracycline (TC) and tetracycline (OTC) in a certain water treatment plant, were examined and analyzed. The variation and removal of antibiotics in the production process of the water plant were studied. A large number of studies have shown that ARGs exists widely in soil, surface water and even underground water. 4 common antibiotic resistance genes, Sul, Sul II, Tet A and Tet G, are selected as the target genes for the safety of drinking water, and a large number of studies have shown that the antibiotic resistance gene (ARGs) is induced by a high number of antibiotics. The real time fluorescence quantitative PCR method was used to quantify the gene concentration in the water plant, and the distribution of 4 resistant genes in the water plant was analyzed. The effect of different catalytic ozonooxidation on the removal of antibiotics was investigated. On this basis, the bioavailability of sulfadiazine in the degradation process was investigated. Different catalytic ozonation techniques were evaluated for degradation and toxicity. The results showed that in the three sample collection, the water plant had 5 kinds of antibiotics, of which the concentration of sulfamethoxazole was 59.40 ng/L and the concentration of erythromycin was the lowest 0.87 ng/L; the content of 5 kinds of antibiotics was presented along the waterworks process. The trend of gradual reduction is that the content of antibiotics in water works is greatly reduced, 2 antibiotics are not detected, and the other 3 kinds of antibiotics are under 7 ng/L. The overall process of the water plant has a good removal effect on the target antibiotics, the total removal rate is 89.9%, in which the ozone oxidation and biological activated carbon treatment unit have the effect of the removal of antibiotics. The total removal rates of Guo Mingxian were 71.2% and 13.1%, respectively. High density sedimentation unit, sand filter unit and chlorination unit have little contribution to the removal of antibiotics, the total removal rate is below 5%. Ozone oxidation and bioactive carbon unit are the depth treatment unit of water plant, high density precipitation, sand filtration and chlorination unit are the traditional parts of water plant. The result of the study shows that compared with the traditional processing technology, the depth treatment process has better effect on the removal of antibiotics. The DNA extraction and fluorescence quantitative PCR detection of the water in the water plant and the effluent of each treatment unit have been carried out. The study shows that the water plant contains 4 kinds of antibiotic resistance genes, Sul? Sul II, Tet A and Tet G The concentration of 2.54 * 10~3copies/ml, 1.36 x 10~3 copies/ml, 1.47 x 102 copies/ml and 0.064 x 102 copies/ml.4 resistance genes showed a trend of decreasing and then decreasing along the process of the water plant. Among them, the content of ARGs in the effluent of the ozonation unit and the effluent of the chlorination disinfection unit was the lowest, and the ARGs was not detected; biological activity was not detected. The content of ARGs in the effluent of sexual carbon unit increased. The concentration of the 4 ARGs was 1.12 x 10~3 copies/ml, 0.18 x 102 copies/ml, 0.05 x 102 copies/ml and 0.14 x 102copies/ml., and different catalytic ozonoooooooooooooooooooooooooooooooooooooooooooooooodiazine was used as the research object, and the individual O_3 oxidation, O_3/H_2O_2, O were compared. The results of the removal of sulfadiazine by _3/UV and O_3/UV/H_2O_2 show that, under the neutral condition, P H has a good removal effect on sulfadiazine by 4 kinds of oxidation technology. When the dosage of ozone is 10mg/L, O_3/UV/H_2O_2 can almost completely remove sulfadiazine. The removal rates of the other three techniques to sulfadiazine are 82.5%, 91.7% and 98.6, respectively. %; when the dosage of ozone is 12 mg/L, O_3/UV can also completely remove sulfadiazine. Therefore, the removal effect of O_3/UV/H_2O_2 on sulfadiazine is better than that of O_3/UV, which is superior to O_3/H_2O_2 alone by O_3 oxidation. The mineralization degree of sulfadiazine by O_3 oxidation alone is lower. When the dosage of ozone is added to 12 mg/L, the removal rate of TOC is 19.6%, and the other three techniques are used. The removal rates of TOC were 34.60%, 46.54% and 55.87%. respectively. As a result, the catalytic ozonation was higher than the individual O_3 on sulfadiazine. In order to further analyze the 4 kinds of ozonization techniques, the biodegradability and biological acute toxicity of sulfadiazine solution before and after oxidation were detected. With the increase of ozone dosage, the biodegradability of the solution increases gradually. The biodegradability of the different catalytic ozonooxidation technology has different effects on the biodegradability of the sulfadiazine solution. When the dosage of ozone is increased from 0 mg/L to 12 mg/L, the content of BDOC in the solution increases from 0.107mg/L to 0.875 mg/L after the O_3 oxidation. By O_3/H_2O_2, the content of the solution is increased to 0.875 mg/L. After the treatment of O_3/UV and O_3/UV/H_2O_2, the concentration of BDOC in the solution increased from 0.107 mg/L to 1.007 mg/L, 1.046 mg/L and 1.29 mg/L., and the results showed that the biodegradability of the solution was stronger after the oxidation of the azimouracil by the ozonoooooooooooooooooooooooooooooooooooooooooooooidazimidine solution to the sulfadiazine solution, respectively, after the statically set of 15 min. The luminescence intensity of the luminescent bacteria was determined, and the inhibition rate of the solution to the luminescent bacteria was obtained. The inhibition of the luminescent bacteria by the sulfadiazine solution at different concentrations before oxidation showed a good linear relationship, the EC20 of sulfadiazine was 562.7 mg/L, and the EC50 was 1235.35 mg/L., with the prolongation of the oxidation time, the inhibition rate of the solution on the luminescent bacteria was gradually increased. When the oxidation time was prolonged to 140 min, the inhibition rates of four kinds of technology to sulfadiazine on luminescent bacteria reached 95.55%, 96.34%, 91.6% and 99.85%. respectively.

【学位授予单位】：山东建筑大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU991.2

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