三氯生在两种典型污水处理系统中去除的研究

发布时间：2018-02-21 09:36

本文关键词： 三氯生降解人工湿地系统同步硝化反硝化系统　出处：《山东大学》2015年硕士论文　论文类型：学位论文

【摘要】：三氯生(Triclosan,简称TCS),是一种人工合成的氯化芳香化合物,常作为抗菌剂、杀毒剂等被广泛应用于个人护理品,医疗用品及家居清洁用品等。TCS每年的全球生产量超过1500吨,环境样品中TCS的检出率相当高。由于TCS及其衍生物具有亲脂性、生物累积性、持久性和生物毒性等特点,它对水生生物、哺乳动物及人类,乃至土壤生态系统都存在着威胁,因此TCS导致的环境问题已经成为国内外研究的焦点之一。而污水处理厂没有专门针对TCS的处理工艺,出水中TCS浓度仍然较高,因此研究更加切实可行的TCS处理方法有着重要的意义。本论文选取两种典型的污水处理技术——人工湿地污水处理系统和同步硝化反硝化系统(SND)作为研究对象,研究其处理含TCS废水的效果,掌握其微生物机制,得到的主要结论如下：(1)挺水植物(香蒲)、沉水植物(金鱼藻)及浮水植物(浮萍)构成的湿地系统中TCS去除率均大于97%。其中,金鱼藻和浮萍系统中,基质及植物吸附对TCS去除的贡献率分别为44.78%和40.25%,远高于香蒲系统(29.12%),在TCS去除中起了很重要的作用。(2)香蒲湿地系统中,微生物的数量和多样性都远高于另外两个系统。已被证明与TCS降解有关的beta-变形菌门,gamma-变形菌门和拟杆菌门在三个系统中均存在,并且,它们在香蒲系统中的OTUs数量比另外两个系统高了20.98%-117.92%,说明微生物降解在香蒲系统中起到很大作用。(3)SND系统对TCS的去除率可达93%以上在。在45天的实验过程中,系统出水、污泥吸附、微生物等其他方式对TCS去除的贡献率分别为1.27%、6.46%和92.27%。TCS投加初期微生物的作用被TCS抑制,TCS的去除主要依靠污泥吸附；污泥吸附逐渐达到饱和,同时微生物对TCS逐渐产生适应性,微生物降解逐渐对TCS的去除发挥主要作用。(4)TCS投加后,SND系统水质净化效果立即变差,NH4+-N去除率由100%降低到88.3%,COD去除率由95.15%降低到65.81%。此后逐渐恢复,并在第14天恢复到较高的去除效果并维持相对稳定。此时微生物已经对TCS产生适应性,细菌群落结构多样性高于TCS投加前,并且,已被证明与TCS降解有关的alpha-变形菌门、beta-变形菌门及拟杆菌门OTUs数量分别增加了4.79%、19.13%和13.31%。
[Abstract]:Triclosan, or TCSA, is a synthetic chlorinated aromatic compound that is widely used as an antimicrobial and antiseptic. TCS is widely used in personal care products, medical supplies and household cleaning products. TCS produces more than 1,500 tons a year. The detection rate of TCS in environmental samples is very high. Because TCS and its derivatives are lipophilic, bioaccumulative, persistent and biotoxic, they pose a threat to aquatic organisms, mammals, humans and even soil ecosystems. Therefore, the environmental problems caused by TCS have become one of the focuses of research at home and abroad. However, there is no special treatment process for TCS in wastewater treatment plants, and the concentration of TCS in effluent is still relatively high. Therefore, it is of great significance to study more feasible TCS treatment methods. In this paper, two typical wastewater treatment techniques, constructed wetland wastewater treatment system and simultaneous nitrification and denitrification system, are selected as the research objects. The main conclusions are as follows: 1) the removal rate of TCS in the wetland system composed of cattail, submerged plant (goldfish) and phytoplankton (duckweed) is more than 97%. The contribution rates of substrate and plant adsorption to TCS removal were 44.78% and 40.25 respectively in goldfish and duckweed systems, which were much higher than those in cattail system 29.12 2, which played an important role in TCS removal. The number and diversity of microbes are much higher than those of the other two systems. Beta-Proteus gamma-Proteus and Bacteroid phylum, which have been proven to be associated with TCS degradation, are present in all three systems, and, The amount of OTUs in the cattail system was 20.98-117.92 higher than that in the other two systems, indicating that microbial degradation played an important role in the cattail system. The removal rate of TCS in the system could reach more than 93%. During the 45-day experiment, the effluent of the system was treated and the sludge was adsorbed. The contribution of microorganism and other methods to TCS removal was 1.276.46% and 92.27% respectively. The removal of TCS by TCS mainly depended on sludge adsorption, sludge adsorption gradually reached saturation, and microorganism gradually became adaptive to TCS. Microbial degradation gradually played a major role in the removal of TCS. After the addition of TCS, the removal rate of NH4-N decreased from 100% to 88.30.The removal rate of NH4-N decreased from 95.15% to 65.81. On the 14th day, the microbes had been adapted to TCS, and the diversity of the bacterial community was higher than that before the addition of TCS, and the microbial community diversity was higher than that before the addition of TCS. The number of beta-Proteus and Bacteroides OTUs, which have been proved to be related to the degradation of TCS, has increased by 4.79% and 13.31%, respectively.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X703

【相似文献】