Enhanced microbial fuel cell for electricity generation from wastewater

• Main Author: Leong, Benjamin Teng Wai.
• Other Authors: Wang Jing-Yuan
• Format: Final Year Project
• Language: English
• Published: 2010
• Subjects: DRNTU::Engineering::Environmental engineering::Waste management
• Online Access: http://hdl.handle.net/10356/40114
• Institution: Nanyang Technological University

Microbial Fuel Cell (MFC) is an emerging technology that has the potential to tap on stored energy in the substrate for waste treatment. MFC is able to disintegrate substrate in the wastewater and at the same time providing electricity generation. Large scale commercial application of MFC is still uneconomical due to the low electricity generation. Therefore, this Final Year Project (FYP) was carried out to identify areas to enhance the electricity generation. In-depth reviews of journal articles had revealed that enhancing the electron transfer efficiency of the anode electrode was very important and thus was proposed and carried out in this FYP. This study had investigated the feasibility of modifying anode electrode through immobilizing mediators on the anode surface to enhance the electricity generation. Shewanella oneidensis was used as the biocatalyst where Luria-Bertani broth was used as the fuel substrate. Four setups were carried out. Three setups were mediators immobilized setups and one was bare Carbon Nanotube (CNT) modified carbon cloth. The three mediators used in the immobilization on CNT were: Neutral Red (NR), Methylene Blue (MB) and Toluidine Blue (TB). Nine scenarios were carried out to evaluate the performance using different resistors. All voltage readings were captured by the multi-meter system. Results had shown that MB performed the best and generated power density (PD) of 354mW/m2 and current density (CD) of 1006mA/m2, followed by TB (PD of 339mW/m2 and CD of 804mA/m2). Comparing to CNT, MB and TB had performance 66% and 59% better than CNT in term of PD. Scanning Electron Spectrometry and Chemical Oxygen Demand tests were carried out and proved that microbial activities and substrate degradation were present in the MFCs test. The experiments had shown promising results and proved that immobilizing mediators on CNT in MFCs system are effective through this study.