TY - JOUR TI - Enhancing energy recovery from biomass waste streams--from mega-landfills and biorefineries to microbial communities DO - https://doi.org/doi:10.7282/T30R9P62 PY - 2010 AB - In the United States, biomass waste streams are often disposed of without consideration for energy recovery. Energy-from-waste (EfW) systems that utilize organic wastes as biomass energy feedstocks could be designed. This dissertation consists of four studies intended to improve energy recovery from biomass waste streams. In Study I, a system-wide energy balance model incorporating the major components of a New Jersey bioreactor-landfill waste management system was developed. The model compared several biogas energy recovery options, identified sensitive areas for optimization, and illuminated future design implications for waste management infrastructure. In Study II, methane generation, predicted by kinetic modeling, and system capital costs were quantified for onsite-batch and regional continuous anaerobic digestion systems handling horse waste in New Jersey. A range of horse quantities, waste methane potentials, and batch reactor sizes, as well as various retention scenarios were compared among each system. Costs and benefits of utilizing smaller onsite digester systems versus larger regional systems to recover bioenergy from horse waste were determined. During traditional anaerobic digestion of biomass, such as municipal solid waste (Study I) or equine waste (Study II), unwanted toxic byproducts, such as ammonia, are liberated as the organic matter degrades. If recovered, however, ammonia can be catalytically converted to generate hydrogen, an additional biofuel. Therefore, in Study III, the effect of ammonia stripping on nitrogen species accumulation and associated energy recovery from laboratory-scale batch reactors was assessed. A simulated organic waste feedstock with various carbon to nitrogen (C:N) ratios was created by varying the fractions of laboratory grade rabbit food, casein and cellulose. Finally, in Study IV, a theoretical design scheme for an integrated system to carry out anaerobic digestion, ammonia separation, and hydrogen recovery was established to determine system energy requirements and biofuel (methane and hydrogen) outputs. Energy demands such as heating, fluid pumping, reactor mixing and ammonia reforming were characterized, and compared to the potential biofuel outputs over a range of possible feedstock C:N ratios. The model was also used to identify significant process tradeoffs to be optimized such as the recycle flux and minimum liquid set point. The model provided a basis and justification for further research of such processes. KW - Environmental Sciences KW - Biomass energy industries--New Jersey--Case studies LA - eng ER -