Thursday, August 16, 2012: 4:30 PM
Meeting Room 9-10, Columbia Hall, Terrace Level (Washington Hilton)
Our urban wastewater infrastructure is aging and in desperate need of repair, or alternatively, re-invention. Bioelectrochemical systems (BESs) exemplify a multidisciplinary approach for creating a new, sustainable infrastructure capable of recovering resources from waste streams. Through the direct biological conversion of organic matter into electrical current, BESs generate electricity, gaseous fuels (hydrogen, methane), desalinated water, and high-value chemicals (hydrogen peroxide, caustic). Despite being a relatively nascent technology, substantial progress in advancing these systems to large-scale applications has been made in recent years. I will discuss this progress with a focus on lab-scale discoveries that have helped make field-scale testing possible. In particular, several promising non-platinized cathodes based on large surface area to volume ratios have been designed for both electricity production in microbial fuel cells (MFCs) and hydrogen production in microbial electrolysis cells (MECs). These developments were subsequently incorporated into the first lab-scale MEC treating wastewater at a winery in California. This 1,000 liter, continuous flow reactor was successful in removing soluble organics (62% removal) with the simultaneous production of current (7 amps/m3-reactor) and gas (mixture of hydrogen and methane). In addition to architectural improvements, I will also discuss our latest understanding of the microbial communities and key electricity-producing bacteria (exoelectrogens) in anodic biofilms.