新型溢流式微生物燃料电池系统运行效果及其应用研究

发布时间：2018-04-03 10:06

本文选题：微生物燃料电池　切入点：膜生物反应器　出处：《浙江大学》2016年博士论文

【摘要】：水资源和能源短缺是当今世界面临的两个主要挑战。对于废水处理工艺而言,在去除污染物和获取清洁水的同时,回收废水中有机物所蕴含的能源,具有非常重大的意义。微生物燃料电池(MFC)是一种通过微生物的催化氧化还原反应将废水中有机物的化学能直接转化为电能的新技术,已成为环境和能源领域的研究热点之一。但是目前的MFC大都采用非生物阴极,并且必须要用质子交换膜(PEM)隔开MFC的阳极室和阴极室,但其价格较贵、易被污染。同时MFC可以被看做是生物膜反应器,相比于溶解性有机物的去除,对颗粒性污染物去除效果不好,因此处理效率不高、出水水质差。这些因素都大大限制了MFC的实际推广应用。本论文开发了一种新型溢流式MFC,因其采用生物阴极,并利用反应器流态而不需要PEM,降低了反应器成本。考虑到溢流式MFC对颗粒性污染物去除效果不好,进一步开发出一种新型溢流式MFC-MBR耦合系统,兼备了膜生物反应器(MBR)的高效截留及选择性分离和MFC产能的优点,展现了良好的产电性能和污染物去除效果。最后提出了溢流式MFC-MBR耦合系统利用不锈钢网生物阴极产生的电能原位抑制膜污染的新思路,并探讨了其机制。主要结论如下：1、开发了一种新型溢流式MFC并评价了其运行性能。该系统能够有效阻断氧气从阴极室向阳极室的扩散,保障阳极室的厌氧环境,同时通过废水从阳极室溢流至阴极室而传递质子。试验结果表明：该系统最大功率密度达到了697mW/m3,对COD、氨氮和总氮的去除率分别为94.9%、97.1%和73.8%,同时对阴阳两极室微生物群落结构分析表明电化学活性细菌富集在电极上并被电流激发,参与到系统的产电或者污染物的去除。2、开发了一种新型溢流式MFC-MBR耦合系统并评价了其运行性能。该系统的不锈钢网和其表面形成的生物膜起到了过滤网和生物阴极的双重作用,实现了系统良好的出水水质和能源回收。试验结果表明：该系统最大功率密度达到了629 mW/m3,废水出水浊度1天之内就由20.3 NTU降到了2.53 NTU,对COD、氨氮和总氮的去除率分别为99.2%、99.5%和84.9%,同时对不锈钢网生物阴极微生物群落结果分析表明生物膜上的反硝化细菌可能是电化学活性细菌或者是被电流所激发,富集在不锈钢网表面的生物膜里,并接纳通过Lactococcus电子传输中介体传输过来的电子。3、提出了溢流式MFC-MBR耦合系统膜污染原位抑制的新思路。考察了该系统的膜污染特性和污泥混合液性质的变化,试验结果表明：该系统的膜污染速率大大降低；在产生的电场、电流对微生物的刺激以及生成的H202共同作用影响下,其阴极室污泥混合液的Zeta电位降低、污泥颗粒较大粒径分布、胞外聚合物(EPS)与溶解性微生物产物(SMP)含量的减少以及SMPp/SMPc的提高。论文还探讨膜污染原位抑制机制,分析表明不锈钢网生物阴极附近产生的电场可以减少污泥颗粒在其表面的沉积,并通过生成的H202可以去除沉积在膜表面的阻塞物,同时,产生的电场、电流对微生物的刺激以及生成的H202会改变污泥的性质,延缓了膜污染的发生。
[Abstract]:The shortage of water resources and energy are the two major challenges facing the world today. For the wastewater treatment process, the removal of pollutants and access to clean water and contained organic wastewater recycling energy, it has a very important significance. The microbial fuel cell (MFC) is a kind of chemical organic matter in wastewater can the new technology directly into electrical energy by catalytic oxidation of microbial reductive reaction has become one of the hot issues in the field of environment and energy. But most of the current MFC by non biological cathode, and must use proton exchange membranes (PEM) separated from the anode chamber and a cathode chamber MFC, but the price is expensive, easy to be at the same time. The pollution of MFC can be seen as biofilm reactor, compared to the removal of dissolved organic matter, the removal effect is not good for particulate pollutants, so the processing efficiency is not high, poor water quality. These factors are. For the practical application of MFC. This paper developed a new type of overflow type MFC, because of the use of bio cathode, and the flow pattern of the reactor without the need for PEM, reduce the reactor cost. Considering the overflow type MFC of particulate pollutant removal effect is not good, the further development of a new type of overflow type MFC-MBR the coupling system, both the membrane bioreactor (MBR) has the advantages of high efficiency and selectivity and MFC interception capacity, show the electricity production performance and pollutant removal effect is good. Finally, the overflow of MFC-MBR coupling system using stainless steel net bio cathode of power in situ suppression of membrane fouling, and discusses the the mechanism. The main conclusions are as follows: 1, the development of a new type of overflow type MFC and its operation performance evaluation. The system can effectively block the oxygen diffusion electrode chamber from the cathode chamber Xiangyang, anaerobic anode protection ring At the same time through the environment, waste water from the anode chamber to cathode chamber and overflow proton transfer. The experimental results show that the maximum power density reached 697mW/m3, COD, ammonia nitrogen and total nitrogen removal rates were 94.9%, 97.1% and 73.8%, at the same time on microbial community structure in the Yin and Yang room analysis shows that the electrochemical activity of electrode in the enrichment of bacteria and by current excitation, involved in the removal of.2 to the system of electricity production or pollutants, the development of a new type overflow type MFC-MBR coupling system and its operation performance and evaluation. The system of stainless steel mesh and the surface of biofilm formation plays a dual role of biological filter and cathode, achieve good system water and energy recovery. The experimental results show that the maximum power density reached 629 mW/m3, the effluent turbidity within 1 days decreased from 20.3 NTU to 2.53 NTU, COD, ammonia nitrogen and total nitrogen The removal rates were 99.2%, 99.5% and 84.9%, while the stainless steel net bio cathode microbial community analysis results show that biofilm denitrifying bacteria could be electrochemically active bacteria or is inspired by the current enrichment in the biofilm surface of stainless steel net, and accepted through electronic.3 Lactococcus electron transfer mediator transmitted and put forward the new idea of inhibition of the in situ overflow type MFC-MBR system for membrane fouling was studied. The changes of membrane fouling characteristics and sludge properties of the system, the experimental results show that the membrane fouling rate is greatly reduced; the electric field generated by the current, influence on microbial stimulation and interaction generated under H202 Zeta, the potential cathode chamber of sludge mixed liquor decreased, sludge particle size distribution of larger particles, extracellular polymeric substances (EPS) and soluble microbial products (SMP) and the decreased S The increase of MPp/SMPc. This paper also discusses the membrane pollution in situ suppression mechanism, analysis shows that the electric field produced near the stainless steel net biological cathode can reduce the amount of sludge particles deposited on its surface, and the generated H202 can remove the deposited on the membrane surface of the block, at the same time, the electric field will change the current properties of sludge on microbial stimulation and the generated H202, delaying the membrane pollution.

【学位授予单位】：浙江大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：X703;TM911.45

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