The biofuels market is currently expanding at a remarkable rate, but a major concern is the continued availability of feedstock needed to meet demand. Previous research by the Renewable Fuels and Chemicals Laboratory (RFCL) at Mississippi State University has shown that microorganisms grown at municipal wastewater treatment plants are a viable source of lipid feedstock for biofuel production. While traditional wastewater plants do produce significant amounts of lipid, the standard plant configuration is designed for minimal production of biomass due to environmental reasons. New or modified plant configurations could give increased lipid yield through changes in process parameters or introduction of new organisms.

The SuperPro Designer simulation package by Intelligen, Inc. was used to simulate wastewater plant configurations for lipid production. Parameters examined include indigenous microorganisms in the wastewater versus the addition of oleaginous yeast for lipid production, pretreatment of the sludge with ozone, addition of acid hydrolysate sugars as a carbon source, and different wastewater feed sources.

Data presented from the simulation models include retention times and sizing data for equipment, characteristics of the effluent streams for EPA compliance, and overall lipid yield. Data on the economics of each design will also be presented.