(639f) The Effects of Process Conditions On Fast Hydrothermal Liquefaction of Microalgae

Transportation fuels are dominated by high energy-density liquids, a vast majority of which are petroleum-based. Petroleum is a finite resource, and the combustion of petroleum fuels releases carbon that had previously been stored underground, contributing to the greenhouse gas effect and global climate change. The production of biofuels from biomass can reduce dependence on petroleum and reduce greenhouse gas emissions. Algae are a particularly desirable biomass feedstock due to their fast growth rates, high oil content, and tolerance for a variety of cultivation conditions. However, algae are inherently very wet, and many biomass conversion processes, like pyrolysis, require dry feedstocks. Hydrothermal liquefaction is an established biomass conversion process that avoids energy intensive drying steps and produces biocrude, a biofuel precursor. Recent research in this field led to the development of fast hydrothermal liquefaction (FHTL), a novel process reducing the amount of time necessary to produce biocrude to perhaps to just 60 seconds. This decrease in reaction time reduces the size of reactor vessels required for continuous biomass conversion, subsequently cutting capital costs associated with such a process. Since FHTL was just recently discovered, there remains a large gap in the literature surrounding FHTL.

This presentation elucidates the effects of time, temperature, heating rate, biomass loading and other process variables on the yields and compositions of biocrudes and various byproducts produced via FHTL. The information gained through this research will identify preferred process conditions for FHTL as the technology is examined and considered for scale-up. Further, characterization of the various byproducts of FHTL will facilitate the environmental decisions that are associated with large-scale processes. Taken together, this information will provide a comprehensive idea of the sustainability of FHTL as a biomass conversion process for the production of liquid transportation fuel precursors.