UNS: Collaborative Research: Systematical Modeling and Control of Microbial Electrochemical Activities towards Efficient Electrical Energy Harvesting

提案编号：1511568/1510682微生物燃料电池含有一种特殊的细菌菌株，它们利用废水中的有机物发电和净化水质。这些系统被吹捧为可持续和“能源积极”的废水处理的一条很有前途的路线。然而，微生物燃料电池系统在广泛使用之前有许多障碍需要克服。其中两个主要问题是低功率输出和可靠性。本项目的目标是将过程控制理论的原理应用到微生物燃料电池系统中，以解决这两个问题。研究计划将侧重于发展对细菌与电力控制系统相互作用的科学理解，并在此基础上开发控制微生物燃料电池功率输出的模型，以提高可靠性。人们还希望，使用这些模型将工艺调整到功率输出的峰值，将使设备中产生最大电流的细菌菌株丰富起来，以进一步提高功率输出。作为该项目教育活动的一部分，本科生将通过科罗拉多大学本科生研究机会计划参与研究。该项目还将与科罗拉多大学技术转移办公室合作，帮助有兴趣将这项研究商业化用于专门废水处理应用的能源公司。微生物燃料电池通过溶解有机物的新陈代谢来发电。典型的微生物燃料电池是两室式的电化学电池，它在阳极室中包含一层具有电化学活性的微生物生物膜，这些微生物代谢溶解的有机物质产生电化学势，并将电子转移到阳极表面，这些电子以电流的形式获得。这一过程产生的质子(H)通过离子交换膜转移到阴极室，在那里它们被阴极表面的溶解氧还原为水。具有电化学活性的微生物具有通过特殊的膜结构将电荷输送到细胞外表面的能力。这项拟议研究的总体目标是利用过程控制和系统理论对微生物电化学活动与为微生物燃料电池设计的外部控制电能收集系统之间的相互作用有一个基本的了解。这项研究的中心假设是，如果微生物燃料电池的运行可以纳入过程控制方案并调整到最大功率输入，那么这个过程将对生长在阳极生物膜内的微生物群落施加选择压力，以丰富电化学活性最高的微生物群，并最终改善电流生成和生物膜的稳定性。在此背景下，研究计划有三个目标。第一个目标是根据可测量和可控制的变量开发一个能源系统模型，以量化单个微生物燃料电池的输入和电输出之间的关系。在此单电池模型的基础上，建立了多电池电池组的能量采集与控制系统模型。第二个目标是了解新的脉冲式功率提取所产生的选择压力如何刺激微生物群落内的生物电化学活动，包括细胞电子转移代谢变化和微生物群落的动态进化。第三个目标是利用电气工程技术，如谐振阻抗匹配、时频域分析和传递函数，来分析和改进系统的性能和可控性。如果成功，拟议的研究将最终形成可扩展和灵活的实时控制方案，以捕获和维护不同条件下多个微生物燃料电池设备的最大可用能量输出，以帮助实现系统可靠性和规模扩大。研究成果还将被整合到科罗拉多大学博尔德大学和丹佛校区的几门可再生能源和水处理课程中。

PI: Park, Jae-Do / Ren, ZhiyongProposal Number: 1511568 / 1510682 A microbial fuel cell contains special strains of bacteria that consume organic matter in waste water to generate electricity and clean up the water. These systems have been touted as a promising route for sustainable and "energy positive" waste water treatment. However, microbial fuel cell systems have many obstacles to overcome before widespread use is possible. Two of the major problems are low power output and reliability. The goal of this project is to adapt the principles of process control theory to microbial fuel cell systems to address these two problems. The research plan will focus on developing a scientific understanding of the interactions of the bacteria with electrical power control systems, and from this understanding, develop models to control the power output of a microbial fuel cell, improving reliability. It is also hoped that tuning the process to peak power output using these models will enrich the device with the bacterial strains that produce the most electric current to further improve power output. As part of the educational activities of this project, undergraduate students will participate in the research through University of Colorado Undergraduate Research Opportunities Program. The project will also work with University of Colorado Tech Transfer Office to help energy companies who are interested in commercializing the research for specialized waste water treatment applications.Microbial fuel cells generate electricity though metabolism of dissolved organic matter. The typical microbial fuel cell is two-compartment electrochemical cell which contains a biofilm of electrochemically-active microorganisms in the anode compartment that metabolizes dissolved organic materials to generate electrochemical potential and transfer electrons to the anode surface, which is harvested as current. Protons (H+) generated by this process transfer across an ion-exchange membrane to the cathode compartment, where they are reduced to water by dissolved oxygen on the cathode surface. The electrochemically active microorganisms have the capacity to transport charge to the outer surface of the cell through specialized membrane structures. The overall goal of this proposed research is to develop a fundamental understanding of the interactions between microbial electrochemical activities and externally-controlled electrical energy harvesting systems designed for microbial fuel cells using process control and systems theory. The central hypothesis of the proposed research is that if microbial fuel cell operation can be put into a process control scheme and tuned to maximum power input, then this process will put a selection pressure on the microbial community growing within the anode biofilm to enrich the consortium for the most electrochemically active microorganisms and ultimately improve current generation and biofilm stability. Within this context, the research plan has three objectives. The first objective is to develop an energy systems model in terms of measurable and controllable variables to quantify the relationships between inputs and electrical output for a single microbial fuel cell. Based on this single cell model, the energy harvesting and control system model for a multi-cell device stack will be developed. The second objective to understand how the selective pressure created by the new pulse-type power extraction stimulates bioelectrochemical activities within the microbial community, including cell electron transfer metabolism shifts and dynamic microbial community evolution. The third objective is to utilize electrical engineering techniques such as resonant impedance matching, time- and frequency-domain analysis, and transfer functions to analyze and improve the system performance and controllability. If successful, the proposed research will culminate in scalable and flexible real-time control scheme to capture and maintain the maximum usable energy output from multiple microbial fuel cell devices under different conditions to help enable system reliability and scale-up. Research outcomes will also be integrated into several renewable energy and water treatment course offerings at the University of Colorado Boulder and Denver campuses.