(782e) Evaluation of Industrial Wastewaters As Fermentation Substrate for Biocrude Production by Enhanced Activated Sludge Cultures

Current studies on evaluating a wastewater treatment plant-based biorefinery concept producing biofuel feedstock lipids and other potentially high-value bioproducts (biocrude) have shown that the carbon source represents a majority of the associated production costs. The process also uses large amounts of wastewater as the fermentation media and nutrient source. This paper will present results of our investigation on the use of high-strength industrial wastewaters as a combined carbon and nutrient source and fermentation medium for activated sludge cultures producing bio-crude. Wastewaters from a pulp and paper mill, landfill leachate, and a dissolved air floatation (DAF) – treated poultry processing wastewater were characterized for biochemical- (BOD) and chemical oxygen demand (COD), nutrient levels, and concentration of major contaminants. These were then tested as stand-alone media or amended with glucose in flask and 3-L bioreactor batch fermentation experiments. Samples were collected and analyzed for biomass and lipid yields, residual sugars and nutrient ions, and COD. Fermentation kinetics modeling will be conducted to determine the biomass growth and lipid accumulation performance of the enhanced activated sludge culture and tolerances towards potential microbial growth inhibitors in the wastewaters. The results will help determine the applicability of industrial wastewaters in the fermentation process and develop pretreatment strategies to remove inhibitory and recalctirant compounds.