Dissertation
Toward practical implementation of bioelectrochemical technologies: From biofilm fundamentals, to scale up, instrumentation, and monitoring and control strategies
Doctor of Philosophy (PhD), Washington State University
01/2019
Handle:
https://hdl.handle.net/2376/111358
Abstract
The discovery of the ability of microorganisms to exchange electrons with inert electrodes – called electrochemically-active biofilms (EABs) – has triggered new areas in fundamental and applied research. However, advancements in the field have been limited by the scope of available technologies and techniques to study, control and scale up EABs. The overall goal of this dissertation was to address some of the bottlenecks limiting the implementation of bioelectrochemical systems in practical applications. This dissertation presents four examples of such bottlenecks. First, we evaluated field performance of sediment microbial fuel cells (SMFCs) using a novel autonomous, battery-operated device. This research allowed us to determine optimum conditions for energy harvesting from SMFCs constructed in Hot Lake, a remote hypersaline lake in northern Washington. Second, we extended this work to address the limited number of isolated microorganisms known to form EABs, which limits the number and diversity of metabolic traits accessible through microbial electrochemistry. This was done by performing long-term chronoamperometric enrichment in a remote area using a newly developed cost-effective battery-operated deployable potentiostat. We demonstrated its utility through the enrichment of microbial community in four alkaline hot springs in the Heart Lake Geyser Basin in Yellowstone National Park, Wyoming. Third, we addressed the limited strategies to control the potential of MFCs, especially when the reactor feed exhibits high daily and seasonal fluctuations in influent flow rate and characteristics, such as the case in MFCs treating real municipal wastewater. To address this, we developed a switchable dual mode system capable of treating wastewater in self-powered MFC mode as well as under potentiostatic control of anodes and cathodes. We demonstrated this system through the operation of a large laboratory scale reactor and pilot scale operated in a local municipal wastewater treatment plant. Lastly, we investigated the factors affecting the scale up of oxygen reducing cathodic biofilms. This addresses the practical challenges in scaling up bioelectrochemical systems, as previous literature documented a significant decrease in current density when increasing electrode surface area. Collectively, this dissertation presents novel technologies and techniques aimed toward expanding the scope and facilitating practical implementation of bioelectrochemical systems.
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Details
- Title
- Toward practical implementation of bioelectrochemical technologies: From biofilm fundamentals, to scale up, instrumentation, and monitoring and control strategies
- Creators
- Abdelrhman Mohamed
- Contributors
- Haluk Beyenal (Advisor)Erik R. Coats (Committee Member)Cornelius F. Ivory (Committee Member)Arda Gozen (Committee Member)
- Awarding Institution
- Washington State University
- Academic Unit
- Chemical Engineering and Bioengineering, School of
- Theses and Dissertations
- Doctor of Philosophy (PhD), Washington State University
- Number of pages
- 316
- Identifiers
- 99900581416001842
- Language
- English
- Resource Type
- Dissertation