典型抗生素在活性炭工艺中的去除及抗性基因研究

发布时间：2019-06-12 13:39

【摘要】：近年来,很多发达国家和地区的水环境中检测出了抗生素,如美国、加拿大、德国、法国、芬兰等发达国家均有在饮用水中发现抗生素等药物的报道。长期饮用含有微量抗生素等药物的水对人类的健康构成威胁,已经引起了全球范围内的关注。而我国是抗生素生产和使用最多的国家之一,有研究表明在对珠江广州河段、深圳河段、黄河等河流的药物检测中发现了抗生素,大部分抗生素含量高于美国、欧洲等发达国家河流中药物含量。水体中长期存在的抗生素必然对水环境产生影响,对现有的饮用水处理工艺处理效果产生影响,尤其微生物是一种适应性很强的生物,水中长期存在的抗生素很有可能会引起微生物体内基因的变化,导致微生物的耐药性增强,并会对饮用水消毒处理产生重要影响。因此,对于水环境中抗生素问题及抗性基因的研究迫在眉睫。 本文以水处理深度处理工艺中的活性炭为研究对象,模拟活性炭及生物活性炭工艺对含抗生素的原水进行处理,并将生物活性炭上附着的生物膜进行培养纯化分析及对细菌的抗性基因检测分析。研究发现,粉末活性炭对一些典型抗生素均有很好的去除效果。当水环境中抗生素的浓度为500ng/L,粉末活性炭的投加量为24mg/L,吸附时间为1h时,粉末活性炭对磺胺甲恶唑、磺胺二甲嘧啶、四环素、土霉素、红霉素的去除率分别达到了79.84%、80.05%、94.62%、83.32%、96.88%。活性炭对抗生素的吸附结果符Freundlich吸附等温线模型,粉末活性炭对不同种类的抗生素表现出不同的吸附特征。 选用3种不同类型的活性炭研究活性炭及生物活性炭对典型抗生素的去除效果。3种活性炭柱中分别装有新炭、A水厂活性炭滤池中的BAC和用抗生素水驯化的BAC。在相同的空床接触时间(EBCT为20min)下,研究3种炭柱对水中初始浓度为500ng/L的抗生素的去除效果。实验结果表明,无论是新炭还是生物活性炭对抗生素均有一定的去除效果,其中温度为20℃C时,新炭对磺胺甲恶唑、磺胺二甲嘧啶、四环素、土霉素和红霉素的去除率分别是90.15%、86.23%、87.90%、79.68%和70.57%。A水厂活性炭滤池中的BAC对磺胺甲恶唑、磺胺二甲嘧啶、四环素、土霉素和红霉素的去除率分别是83.28%、80.56%、55.08%、70.17%和82.17%,用抗生素水驯化的BAC对磺胺甲恶唑、磺胺二甲嘧啶、四环素、土霉素和红霉素的去除率分别是72.04%、69.34%、57.67%、49.78%和67.32%。温度对活性炭及生物活性炭对一些典型抗生素的去除有重要影响,随着温度的降低,新炭对抗生素的吸附性能力提高,但生物活性炭对这些物质的生物降解能力有所下降。 试验研究结果表明生物活性炭上的微生物主要由细菌组成,以革兰氏阴性菌为主,未检测出致病菌,从生物活性炭柱下层、中层和上层BAC分离的细菌主要类群基本相同,但其生物量沿水流方向减少。进水中抗生素可诱导细菌体内产生抗性基因,使细菌对抗生素的耐受性和抗氯性均增强,当进水抗生素浓度为500ng/L,运行5个月后生物炭生物膜对抗生素的耐受强度可达10mg/L,抗氯强度可达5mgCL2/L。当用抗生素水诱导细菌具有了抗性基因后,在长期进水不含抗生素的原水作用下,抗性基因很难再消失。即抗性基因一旦产生,就会存在于环境之中,分布和传播,是一种新型的环境污染物。
[Abstract]:In recent years, many developed countries and regions have detected antibiotics in the water environment such as the United States, Canada, Germany, France and Finland. The long-term drinking of water, including micro-antibiotics, poses a threat to human health and has given rise to global concerns. In China, one of the most important countries in the production and use of antibiotics is the discovery of antibiotics in the drug detection of the river, Shenzhen and the Yellow River in the Pearl River, most of which are higher than those in the developed countries such as the United States and Europe. The medium and long-term antibiotic in the water body has an effect on the water environment, and has an effect on the treatment effect of the existing drinking water treatment process, in particular to a microorganism which is strong in adaptability, and the long-standing antibiotic in the water can cause the change of the gene in the microorganism body, The drug resistance of the microorganism is enhanced, and the sterilization treatment of the drinking water has an important effect. Therefore, it is urgent to study the antibiotic problem and the resistance gene in the water environment. In this paper, the active carbon in the water treatment depth treatment process is used as the research object, the active carbon and the biological activated carbon process are simulated to treat the raw water containing the antibiotic, and the biological membrane attached to the biological activated carbon is subjected to culture purification analysis and the detection of the resistance gene of the bacteria. The results show that the active carbon has good effect on some typical antibiotics. When the concentration of the antibiotics in the water environment is 500 ng/ L, the dosage of the powdered activated carbon is 24 mg/ L, the adsorption time is 1 h, the removal rates of the powdered activated carbon on the sulfanilamide, the sulfanilamide, the tetracycline, the oxytetracycline and the erythromycin are 79.84%, 80.05%, 94.62%, 83.32%, 96.88, respectively. %. The adsorption results of activated carbon on antibiotics, Freundlich's adsorption isotherm model, and powdered activated carbon showed different adsorption to different kinds of antibiotics. 3 different types of active carbon were used to study the effect of activated carbon and biological activated carbon on the removal of typical antibiotics. BAC. In the same air-bed contact time (20 min, EBCT),3 carbon columns were studied for the removal of antibiotics with an initial concentration of 500 ng/ L in water The results showed that the removal rate of the new carbon to the sulfanilamide, the sulfanilamide, the tetracycline, the oxytetracycline and the erythromycin was 90.15%, 86.23% and 87, respectively, when the temperature was 20 鈩，

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