(639g) Hydrothermal Liquefaction of Wastewater Derived Green Alga

Hydrothermal liquefaction (HTL) of algae has gained fast popularity within the research community because if it’s superior pairing with algae as a conversion process to fuels and chemicals.  HTL is a whole cell conversion process not limited to high-lipid content algae for high biocrude yields; typically 10-30% higher than initial lipid content, and uses subcritical water chemistry as the chemical driving force reducing the need for extensive dewater and solvent extraction as with pyrolysis and biodiesel production.  The carbon rich biocrude product from HTL is most similar to that of petroleum crude than any other bio-oil reported to date.  It has recently been reported that combining HTL conversion and wastewater cultivation relieves many of the sustainability concerns as identified by the National Research Council.^{1, 2} Wastewater derived algae gives very different product profiles compared to fertilized controlled-growth cultivated algae, mainly in terms of biocrude molecular and elemental content with a great increase in solid biochar production.  This paper reports on the HTL of various green algae and evaluates the feedstock and products in terms of its yield and characterized by GC-MS, calorimetry, DSC/TGA, FT-IR, ICP-OES, elemental content, and distillate fractions.

References:

1)      National Research Council of the National Academies. Committee on the Sustainable Development of Algal Biofuels. Sustainable Development of Algal Biofuels in the United States; National Academy Press: Washington, D.C., 2012.

2)      Griffin W. Roberts, Marie-Odile P. Fortier, Belinda S. M. Sturm, and Susan M. Stagg-Williams, Promising Pathway for Algal Biofuels Through Wastewater Cultivation and Hydrothermal Conversion, Energy and Fuels,  27 (2), 857–867 (2013).