Master of Science, The Ohio State University, 2014, Food, Agricultural and Biological Engineering

Microbial Fuel cells (MFCs) can be used to generate bioenergy in the form of electricity using microorganisms and natural biological processes. The need for a supply of fresh water in many parts of the world has led to the innovation of modifying an MFC into a Microbial Desalination Cell (MDC) that adds the function of desalination to the MFC's existing ability to generate electricity directly from cellulosic feedstocks. The goal of this project was to design and analyze the use of a Microbial Desalination Cell (MDC) for the generation of electricity while simultaneously desalinating saline water. Potential applications include desalinating seawater for coastal drinking water supplies or ocean-going shipboard water supplies, and decontaminating oil shale hydraulic fracturing wastewaters. The newly designed MDC incorporates marine algae Nanochloropsis Salina in the MDC's cathodic chamber to harvest solar energy and maintain a fresh supply of oxygen to the cathode electrode. The anodic chamber incorporates the use of enriched cellulose degrading rumen microbial consortium. This system, which was operated in a fed batch mode, included a central desalination chamber with 35 parts per thousand of saline water. The fully functional MDC had the salt removal efficiency of 100% and the maximum power density of 35.73 micro-Watt per square meter.

Committee: Ann Christy Ph.D., P.E., (Advisor); Zhongtang Yu Ph.D. (Committee Member); Yebo Li Ph.D. (Committee Member) Subjects: Biology; Electrical Engineering

Master of Science, The Ohio State University, 2015, Food, Agricultural and Biological Engineering

With a growing global population and a higher demand for potable water, society relies on Reverse Osmosis (RO) for large-scale desalination. Reverse Osmosis is currently the most economic and commonly used method to desalinate saline or brackish water to produce potable drinking water. This research investigated the alternative use of Microbial Desalination Cells (MDCs), and compared MDC technology to RO by performing life cycle and economic analyses. The additional advantage of an MDC, as compared with an RO desalination plant, is the production of a small amount of electricity as a by-product of the microorganisms' anaerobic respiration in the MDC device. The goal of this project was to determine if this production of electricity was enough to make MDC technology a more sustainable and economically favorable long term desalination option. A currently operating reverse osmosis plant was analyzed along with a laboratory scale MDC. Given that the RO facility under investigation is much larger than the bench scale MDC, both analyses were normalized on a per cubic meter basis, for implementation in Columbus, Ohio, USA. Results indicate that although the MDC is not currently the more sustainable option, design improvements can be made to the MDC that will make this technology much more promising in the future.

Committee: Ann Christy (Advisor); Bhavik Bakshi (Committee Member); Matthew Roberts (Committee Member) Subjects: Agriculture; Alternative Energy; Environmental Management; Environmental Science; Sustainability; Water Resource Management