Waste-wood derived biochar was evaluated for the first time as both an anode and cathode material, simultaneously, in an overflow style microbial fuel cell (MFC) using actual industrial wastewater. Results show that the average chemical oxygen demand (COD) removal was 95% with a reduction rate of 0.53 kg times COD times m-1 times d-1 in closed operation mode. The ammonia and phosphorous reductions from wastewater was 73% and 88%, respectively. Stable power production was observed with a peak power density measured at 6 W/m3. Preliminary contributions of physical, biological, and electrochemical COD removals were evaluated, and the results show such combined mechanisms give BC an advantage for MFC applications. Nutrient recovery data showed high levels of macronutrients adsorbed onto the spent biochar electrodes, and phosphorus concentration increased from 0.16 g times kg-1 in raw BC to up to 1.9 g times kg-1 in the cathode. These findings highlight the use of biochar as electrodes in MFCs to facilitate simultaneous wastewater treatment and power production with additional agronomic benefits.
Huggins, Tyler M.; Latorre, ALbert; Biffinger, Justin C.; and Ren, Zhiyong Jason, "Biochar Based Microbial Fuel Cell for Enhanced Wastewater Treatment and Nutrient Recovery" (2016). Civil Engineering Faculty Contributions. 2.