【作者】 吕英；

【导师】 孙宝盛；

【作者基本信息】 天津大学 ， 环境工程， 2007， 硕士

【摘要】 在污水处理工艺日益改进的今天,研究学者加大了对活性污泥胞外聚合物（EPS）的性质和功用的研究。其中包括对其提取方法的研究,其提取方法分为物理方法和化学方法,寻找出既能保证EPS的结构和又能将其提取完全的方法是急需解决的问题。另外,胞外聚合物做为一种新型的生物吸附剂来吸附重金属离子越来越受到人们的重视,人们注意到在活性污泥法处理工艺中,胞外聚合物对重金属离子的去除发挥着重要的作用,从而将提取出来的胞外聚合物做为金属离子的吸附剂加以应用成为国内外研究的热点课题。本文从这两个研究方向入手,一方面以膜生物反应器活性污泥为原材料,通过三种物理方法:热提法、高速离心法和超声波法从中提取出胞外聚合物,对每种方法的提取条件进行适当的变化,从而找出各自的最优提取条件,在各自最优条件下分别提取出一定量的胞外聚合物,进行对比比较,从而找出最佳的提取方法。另一方面,利用最佳方法提取出一定量的胞外聚合物作为吸附剂,研究其对Cu²⁺、Ni²⁺和Cr³⁺这几种重金属离子的吸附去除效果,寻求最佳的吸附条件,考察其作为金属离子的生物吸附剂的可行性。同时,研究EPS在贵重金属离子（Ag+）的回收上的实用价值。实验的结果表明在这三种物理方法提取结果当中,热提法（80℃,15min）提取的胞外聚合物的量最多而且对细胞的破坏程度也比较小,为最佳提取方法。胞外聚合物对Cu²⁺、Cr³⁺和Ni²⁺三种重金属离子吸附适宜pH值分别为3～5,4～6和4～6;适宜投加比例（EPS质量:金属离子质量）分别为1.8:1,1.6:1和2:1,EPS对不同的金属离子吸附机理不同,对一种金属离子吸附饱和后对其他金属离子同样有吸附作用。对贵重金属离子Ag⁺有一定的吸附作用,从而将胞外聚合物用于贵重金属离子的回收有一定的潜力。更多还原

【Abstract】 With the increasing advance of sewage disposal craft,research scholars increase the studies on property and funtion of active sludge extrocellular polymeric substances （EPS）.The studies include the research on method of its extraction,which is divided into physical method and chemical process,and finding out the method that is both able to guarantee EPS structure and able to extract entirely is an urgent problem.In addition ,with the incresing recognition on EPS as a sort of newfashioned biosorption agent absorbing heavy metal ion, it is noticed that EPS is important for the removal of heavy metal ions in activated sludge treating process and it used as metallic ion adsorbent become both domestic and overseas researchful hotspot.The paper starts with the above two researchful directions.On the one hand extract EPS from raw and processed materials that is membrane bio-reactor active sludge through the medium of three strain physical methods that include heating extration, supercentrifugal process and ultrasonic method. Proper changing per strain methodological abstraction condition proceeds and thereby hunts respective optimal abstraction condition. Contrast a given mass of EPS extracted in respective optimum conditions and thereby find out optimal method of extraction.On the other hand study EPS as adsorbent,which is given by best extracted way,adsorption removal effect versus heavy metal ion that includes Cu²⁺,Ni²⁺ and Cr³⁺.And seek optimal adsorption condition,review its feasibility as metallic ion biosorption agent. At the same time research the using value of EPS at reclaiming precious metal ion（Ag+）.The experiment shows optimal method of extraction is heating extraction （80℃,15min）which extracts the most EPS measure and furthermore level of destruction on cell is the smallest in three strain physical method extraction outcome. The proper pH value on Extrocellular polymer （EPS） respectively absorbing three kinds of heavy metal ion including Cu²⁺,Ni²⁺ and Cr³⁺ is 3～5,4～6和4～6. The fitting throwing scale（EPS quality:Metallic ion quality）is 1.8:1, 1.6:1 and 2.0:1 respectively. EPS has different adsorption mechanism versus different metallic ion and can also absorb the rest metallic ion after a sort of metallic ion adsorptive saturation. EPS designed to reclaim heavy metal ion has definite potential as it has definite sorption versus precious metal ion Ag⁺.更多还原