472961 Flash Pyrolysis and Fractional Pyrolysis of Oleaginous Biomass in a Fluidized-Bed Reactor

Wednesday, November 16, 2016
Grand Ballroom B (Hilton San Francisco Union Square)
Brook Urban1, Yaser Shirazi1, Balakrishna Maddi2, Sridhar Viamajala1 and Sasidhar Varanasi1, (1)Chemical and Environmental Engineering, The University of Toledo, Toledo, OH, (2)Pacific Northwest National Laboratory, Richland, WA

In this study, flash pyrolysis of oleaginous biomass was investigated to produce liquid fuels. Milled soy flakes were used and can be considered a surrogate for algal biomass due to similar compositional, proximate, and ultimate characteristics. A fluidized-bed flash pyrolysis was designed and constructed to facilitate rapid heat transfer to the biomass along with short vapor residence times to minimize secondary degradation of bio-oils and achieve high yields of bio-oil. In addition, a dry-ice packed bed condenser was used to recover the generated vapors. The novel condenser provides a large area of cold surfaces that allow dilute vapors to impinge, condense and coalesce effectively. Single-step pyrolysis experiments were performed at several temperatures over the range 250-610°C with a vapor residence time between 0.3-0.6s. Biooil yields were highest at 550°C (~70% g/g-feed) with only a 12% loss as uncondensed vapors. Moreover, 90% of the feedstock lipids were recovered in the bio-oil fraction. In addition, three-step fractional flash pyrolysis experiments were performed to assess the possibility of producing higher quality bio-oils since a large fraction of protein and carbohydrates degrade at lower temperatures (310-350°C). A low temperature pyrolysis step (250ºC) was first performed and was followed by pyrolysis of the residues at higher temperatures (310 and 530ºC). The bio-oil from last step (530ºC) resulted in higher quality bio-oil with low water- and nitrogen- content, and high heating value of 33 MJ/kg.

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See more of this Session: Poster Session: Sustainability and Sustainable Biorefineries
See more of this Group/Topical: Sustainable Engineering Forum