(271g) Conversion of Wastewater Treatment Facilities into Biorefineries

Oleaginous microorganisms can produce up to 70 percent of their body weight in oil. The use of these microorganisms as a source of oils for biofuel production is limited by the availability of cost effective carbon and water sources. A growth medium that has not been introduced for cultivating oleaginous microorganisms is municipal and industrial wastewater. This study is designed to determine if a consortium of oleaginous microorganisms can be cultivated on municipal wastewater to produce an abundant amount of oil while treating this water to Environmental Protection Agency (EPA) required levels. These experiments were conducted in a batch process using synthetic wastewater, proposed by LaPara et al. Oil percentage, oil yield, and growth rate are measured using well-established techniques. Also, water quality was measured by determining the biochemical oxygen demand (BOD), the chemical oxygen demand (COD), and the amount of nitrates in the wastewater after the yeast growth stabilizes. These quantities will determine the efficacy of the oleaginous microorganisms assist in removing wastewater contaminants. Preliminary results show that the microorganisms are consuming indigenous oils when cultivated after a 72-hour growth period. These results also show an average COD reduction of 83.4 mg/L. Wastewater treatment facilities may be operated with oleaginous yeasts as the main consumers of BOD. This modification could potentially generate billions of gallons of oil for producing biofuels.