Development of a mobile, pilot scale hydrothermal liquefaction reactor: Food waste conversion product analysis and techno-economic assessment

The purpose of the present work is to investigate the feasibility of hydrothermal liquefaction (HTL) on food waste using a mobile pilot scale reactor and assess its techno-economic potential as a renewable energy technology that can be commercialized in the future. A 35 L pilot scale reactor (0.15 Gal·min⁻¹, 300 °C, and 60 min retention time) resulted in a higher biocrude oil yield than lab scale reactors (29.5 wt% vs 21.9 wt%). Biocrude oil qualities from pilot scale and lab scale HTL showed similar characteristics when comparing the elemental distribution, oil composition, and heating values. Further, techno-economic assessment (TEA) showed that the minimum selling price of the biocrude oil from a base case scenario was $3.48 per gallon gasoline equivalent (GGE). The transportation cost of the feedstock and oil product was compared between onsite and mobile scenarios of HTL reactor operation. The results demonstrated that the mobile HTL reactor was more profitable when the sources of food waste were widely distributed (more than 106 miles). Combined pilot reactor results and assessments in different scenarios could be used to assess the sustainability of the HTL process for future large-scale implementation.