25 Biomass Conversion Processes For Energy Recovery Massoud Kayhanian and George Tchobanoglous University of California at Davis Robert C. Brown Iowa State University 25.1 Energy Recovery by Anaerobic Digestion ........................ 25-2 Introduction Organic Wastes and Biomass Used as Feed- stocks in Anaerobic Digestion Process The Issue of Biodegradability Fundamental of Anaerobic Digestion Monitoring of the Anaerobic Digestion Process Reactor Types Used for Anaerobic Digestion Modes of Operation for Anaerobic Digestion Utilization of By-Products from In-Vessel Anaerobic Digestion Process Commercial-Scale In-Vessel Anaerobic Digestion Technologies References ....................................................................................... 25-34 25.2 Power Generation............................................................. 25-37 Introduction Direct Combustion Combustion Equip- ment Thermal Gasification Stirling Cycle Rankine Cycle Brayton Cycle Fuels Cells Combined Cycles References ....................................................................................... 25-50 25.3 Biofuels.............................................................................. 25-51 Introduction Ethanol Ethanol from Starch Crops Ethanol from Lignocellulosic Feedstocks Biodiesel Transportation Fuels from Biomass-Derived Syngas References ....................................................................................... 25-65 25-1 q 2007 by Taylor & Francis Group, LLC