Topic: Bioelectrochemical Systems – from fundamentals in robotics to real world applications

When: 18th Jan, at 10:30 a.m.

Where: meeting room 4th floor, building L

Speaker: Prof. Ioannis A. Ieropoulos from Water & Environmental Engineering Group, Civil, Maritime and Environmental Engineering
Faculty of Engineering and Physical Sciences, University of Southampton

Annotation: Microbial fuel cells (MFCs) is a promising platform technology for a number of applications. MFCs work on anaerobic/electroactive microbial metabolism, which results in electricity being produced whilst organic matter (consumed as fuel) is being treated. MFCs usually consist of two half-cells, separated by an ion exchange membrane and electrons flow from the bacterial (negative) half-cell, to the positive half-cell, through a circuit. Amongst a plethora of organic waste products and materials tested in MFCs, human urine has been reported as an effective fuel for electricity generation. Urine is responsible for 10% of organics, 75% of nitrogen and 50% of phosphorous found in domestic wastewater, and yet volumetrically, it only constitutes less than 5% at municipal level. It is therefore of significantly advantageous if waste separation was implemented at source, for more efficient downstream wastewater treatment.

This talk will present results from the practical implementation perspective of MFCs in a range of applications, thereby making the case for a platform technology that can be used in off-grid and citywide inclusive environments. The talk will show the chronological development of the technology, from the early robotics implementation to the most recent application in sanitation. Work from the Urine-tricity programme that has been running for 10 years, showing the potential of MFCs in treating human urine will be presented. Different MFC designs, including ceramic-based with power generation and organics degradation are being discussed. When ceramics are appropriately exploited, this results in the generation of an electrochemically activated solution, known as the catholyte, which is a valuable by-product that can be used as a disinfectant. This catholyte is an alkaline, high in salt (thus high in conductivity) liquid that is produced due to the electro-osmotic drag and has been shown to achieve pathogen killing. MFCs can also be generally used as a biosensor to monitor the organics in an aqueous medium, through the analogue signal produced. The MFC technology has also been successfully scaled up and implemented as a power source for lighting, in remote, previously unsafe toilet environments, and for this reason, has been named Pee Power®. More recently, emphasis has been given on the pathogen killing properties of MFCs, whilst generating electricity and results from this work will also be presented for different pathogenic species.

The talk concludes with the case for microbial fuel cells as a platform technology for multiple a range of environments including sanitation, renewable energy generation, production of value-added products via elemental recycling and wastewater treatment.