(316c) Production of Renewable Fuel From Enhanced Activated Sludge Through a Fluidized-Bed Catalytic Cracking (FCC) Process

Annual production of activated sludges in the United States ranges from 7 – 8 million tons.  Currently, disposal technologies of these sludges include incineration and landfilling, both of which are heavily regulated and could create adverse environmental impacts.  A fraction of the activated sludges can be used as fertilizer once it complies with regulations for Class A biosolids.  Activated sludges contain microbial consortia known to produce lipidic materials and many other organic compounds, which could be used as fermentation seed for enhancement of its lipid content. Several studies showed that reasonable yields (2 – 6% weight) of biodiesel could be produced from activated sludge.  At these yields however, activated sludge biodiesel is less economical than petroleum diesel.  By increasing the fuel yield, which could be accomplished by enhancement through fermentation, in combination with an in situ catalytic conversion to fuel, the economics of this feedstock could be improved. This study describes the production of renewable fuel from enhanced activated sludge using Fluidized Catalytic Cracking (FCC).  This process could convert most of the compounds present in sludge into fuel, and thus, increase fuel yields and reduce cost.