An assessment of GHG emissions of two organic waste processing options for UBC Chen, Xinyi; Hamdy, Hany McRea; Wells, Ralph
In our study, we evaluate two food waste processing options for the University of British Columbia for emissions of greenhouse gasses. We considered an on-campus option based on the existing UBC in-vessel aerobic composting system, and an off-campus option based on an anaerobic digestion system located in Richmond, BC that generates energy from biogas. We found that of the two options we considered, the off-campus anaerobic digestion option had net 52 tonnes lower CO2e emissions than the on-campus option based on the emission factors and assumptions we used. We found that emissions from food waste diverted to landfill for the on-campus option and carbon stored in soil from compost were the most significant factors affecting emissions. We further found that emissions related to transportation were minor relative to other emissions as were emissions from electricity used for the on-campus facility. We conclude that both options provide significant reductions relative to sending food waste to regional waste disposal facilities. We recommend that UBC consider the benefits of including a waste sorting system to reduce or eliminate rejected food waste in any future processing options implemented by UBC. Further work could focus on completing energy and mass balances for the off-campus option, and determining associated emissions. A full life cycle analysis could consider the fate of all campus food waste (not just waste diverted to organic processing facilities) and evaluate a range of human health and environmental impact factors.
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Attribution-NonCommercial-NoDerivs 2.5 Canada