Techno-economic Assessment of a Hydrothermal Liquefaction Process for Energy Recovery from Food Waste

Hydrothermal technologies have been extensively studied over the last decade as promising pathways for energy recovery from bioresources. Feedstocks with a high moisture content, such as food waste, are particularly suitable to undergo hydrothermal conversion. In this work, we addressed a techno-economic study of the production of food-waste-derived biofuels via Hydrothermal Liquefaction (HTL), in a commercial scale facility. To that end, a simulation model encompassing the HTL conversion step (including the combination of two kinetic models from bibliography), bio-oil upgrading and products separation was implemented in Aspen Plus® V10. Results show that both the predicted biocrude mass yield in HTL (37 %) and its composition are consistent with those of previous experimental studies. Amongst the products, the annual volumetric production of gasoline triples that of diesel. In terms of the economic viability, under the studied assumptions, we found the project would only be profitable if a fee (27-39 €/t) accounting for waste treatment is adopted.