Thesis Archive
A Comparative Life Cycle Assessment of Carbon and Nitrogen Flows Between Diesel and Coconut Biodiesel Production
Cruz, Jazel
Maulion, Trishia Colyn
Pangilinan, Fiona Marian
Abstract:
Fossil fuels, which are non-renewable resources, have long been the main energy source used by humans. However, the dependency of the world on fossil fuels poses great risks to both human health and the environment due to the different environmental impacts, such as global warming and acidification, associated to them. Thus, renewable energy sources are much sought after. Biodiesel has been a prominent choice as an alternative fuel to conventional diesel because of its ability to reduce CO2 emissions. However, its nitrogen footprint has increased due to the fertilizers used to grow the feedstock, and since it is relatively high in oxygen content, it favors the formation of nitrogen oxides when combusted. Furthermore, there are very few literatures published about nitrogen footprint as compared to carbon footprint. In this study, a comparative life cycle assessment with the ISO 14040 standard was done for both conventional diesel and coconut biodiesel production, which had four scenarios, using SimaPro v.9.0.0.35. The scenarios were a combination of either fertile or infertile land and with or without co-product utilization. The amount of C footprint and N footprint for conventional diesel amounted to 4,828.425 g CO2-eq and 2.989 g NO3-eq per km travelled by a vehicle. It was determined that the preferred pathway to produce coconut biodiesel is by farming coconut trees on a fertile land and using the co-products, husks and shells, as source for biomass cogeneration. This scenario produced the least amount of C and N footprint among the four with 4249.069 g CO2-eq and 11.704 g NO3-eq. The fertilizer production was the process that greatly affected the emissions of the life cycle in all scenarios due to the electricity consumption and the fuel requirement of the machineries. When a sensitivity analysis was done, changes were observed when the factors: fertilizer utilization, oil extraction/refining efficiency, and biodiesel yield were varied. It was then concluded that the Philippines could gradually shift to using higher biodiesel blends if improvements could be made on the area of fertilizers in order to minimize the emissions as much as possible.
Adviser:
Aviso, Kathleen B
Razon, Luis F