"Zoos across the country are pushing for sustainable solutions to mitigate their high-energy consumption and provide organic waste management. Anaerobic digestion provides an alternative to traditional waste management solutions such as landfilling, incineration, and composting. The Detroit Zoological Society (DZS) was selected as the zoo for this study. This study analyzed seven waste samples and mixtures from the DZS. A biochemical methane potential (BMP) test was performed on these wastes and their mixtures to determine the energy content. The results show that all samples are anaerobically biodegradable with samples yielding 501, 622, 269, 117, 232, 653, and 302 L biogas per kg initial VS for carnivore, primate, hoofstock mix, bird mix, zoo mix, food waste, and ZMF, respectively. The energy balance and carbon footprint analyses on BMP data further conclude that anaerobic digestion can efficiently handle zoo wastes, generate renewable energy to compensate 1.4% of the zoo's energy demand for their animal operations, as well as reduce carbon dioxide emission by 16%. In addition, the zoo mix and ZMF samples were tested in small-scale pilot digesters. Results show that the zoo mix sample yielded the highest cumulative gas production while the ZMF sample indicated inhibition due to low operating pH. The zoo mix and ZMF samples were fit to the Modified Gompertz Equation model to determine performance parameters for scale-up considerations."--Page ii.
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