Discipline: Ecology Environmental and Earth Sciences
Subcategory: Pollution/Toxic Substances/Waste
Samuel B. Lum - Rochester Institute of Technology
Increasing levels of anthropogenically generated food waste have become an issue due to excessively high chemical oxygen demand (COD) levels which can reduce the amount of dissolved oxygen in water. One example is that an excessive amount may cause life-threatening hypoxic conditions for aquatic wildlife. An effective way to address and mitigate the pressing global concern of these pollutants is through Microbial Fuel Cell (MFC) treatment. MFC technologies stands as a renewable energy source powered directly by bacterial digestion. This electricity is harvested through an electrochemical process from bacteria, as they oxidize a substrate at the anodic chamber section. These substrates can range from organic material including food waste and wastewater. Thermal heat, energy, natural gas and water are all biochemical byproducts of the redox reaction on top of effective wastewater treatment. This electrochemical potential is drawn from the bonds of organic material through catalytic reactions that occurs when the cell is under aerobic conditions. Noting this, MFCs easily become of the most natural fuel cells with a large potential to solve multiple environmental problems. Experimentation factors that impact MFC performance include material, chemical and test environment considerations. This research is one of many that continues to build the foundation of sustainable technology, and specifically focuses on understanding wastewater treatment and the circumstances on what allows for efficient reduction via microorganisms. All six substrates used in the experiments are locally sourced waste from RIT, these substrates are full strength tofu whey, diluted tofu whey, cow manure, glucuronic acid, organic food wastes and cellulose. Through research with these six different effluents, it was found that the cell highest in volatile solids had the highest electrical output and one of the highest improvement in reducing chemical oxygen demand (COD), a measure of water quality. Through extensive data collection, it was found that, with a 16 day operational run, the cells that ran glucuronic acid and cellulose had a respective COD reduction of 83% and 91% respectively; both began at about 2000 mg/L of concentration diluted with water. Cellulose and glucuronic acid are both found in leafy greens. Test data was provided through a data acquisition system rigged to each cell with a voltmeter and thermocouple. Supporting the significance of glucuronic acid and cellulose, both cells had above average internal cell temperatures and cellulose had the highest temperature increase of 13℉. This concludes a highly effective reduction of COD pollutants and overall wastewater treatment. Through bioengineering and electrochemistry, future experiments look to find unique ways to improve the bacterial metabolic process and overall cell performance. Near future investigations include conducting a multi-factorial design of experiments to understand the correlation between various test conditions on microbial ecology. Furthermore, upon isolating the best conditions from the experiments, additional chemical probes will be utilized to understand the performance of the cell signalling pathways as the bacteria oxidize waste and will push for more comprehensive watertreatment tests. This will help look at the microbiology of the best cases to optimize further. The end goal being to effectively treat wastewater using the most cost effective fuel cells.
Funder Acknowledgement(s): Golisano Institute of Sustainability
Faculty Advisor: Steven Barber, sxl9991@rit.edu
Role: I took initiative to establish this project by arranging meetings with professors university-wide to better understand the research goal, especially since the concepts were outside of my field. Countless hours were spent ensuring the research itself was unique and could eventually be stand-alone. I gathered the sources, took, processed the thousands of data points, began the introduction and abstract of a research paper. Took initiative to present at two conferences and still exploring and continuing the research.