Life Cycle Assessment of Green Transportation Fuels Produced from Algal Biomass Via Hydrothermal Liquefaction

A life cycle assessment (LCA) study is performed for the energy requirements and greenhouse gas emissions in the production of transportation fuels from algal biomass. Different fuel production pathways have been studied to produce different types of transportation fuels. This study uses hydrothermal liquefaction (HTL) as the primary method to produce biocrude oil from algal biomass. Fuel production pathways studied in this work include the production of biodiesel, green diesel, green gasoline, and green jet fuel.  A sensitivity analysis is conducted to identify the key factors affecting the total energy consumption in the production of green transportation fuels from algal biomass. Net energy demand requirements are calculated with/without coproducts to identify a suitable production pathway for sustainable transportation fuel production. Importance of co-product management to achieve sustainable transportation fuel is discussed. A well-to-wheel analysis has been conducted to assess the greenhouse gas emissions in all production processes.