Hydrothermal Liquefaction of Food Waste and Remediation of Aqueous Byproducts

Thermochemical processing via hydrothermal liquefaction (HTL) is capable of processing a broad range of feedstocks, has a favorable net energy ratio, and produces an energy-dense liquid biooil product.However, there is an obstacle with current HTL processes that has hampered the adoption of this technology—the HTL process produces a considerable amount of aqueous organic byproducts and HTL oil requires upgrading to be used as a drop-in fuel.The formation of aqueous-phase organics can be minimized by using heterogeneous catalysts and by post-processing the aqueous phase to remove the dissolved organics.Mainstream Engineering has combined these two approaches to improve the environmental and economic aspects of food waste HTL.By addressing the aqueous waste hurdle, this project will catalyze the adoption of HTL to convert high-moisture waste biomass to renewable fuel.We will continue this work by upgrading HTL oils into a saleable product and by automating and refining the HTL/HTG reactor.Prof.Timko of Worchester Polytechnic Institute will develop new catalysts to hydrotreat the HTL oil phase and characterize catalyst deactivation.Mainstream will update the HTL/HTG reactor, operate an oil burner using HTL oil, and demonstrate online regeneration of the hydrotreating catalyst.The end result will be a process to efficiently convert wet food waste to a saleable biooil product.The proposed hybrid HTL/HTG process is focused on the conversion of waste biomass material to a renewable fuel that would displace petroleum-derived fuels, thereby addressing both a waste disposal challenge and a renewable fuel challenge.The public will benefit from renewable energy and reduced environmental impacts from liquefaction processes.