Advancing integration of Hydrothermal Liquefaction Aqueous into WRRF Digestion Processes and Assessing PFAS fate

Hydrothermal liquefaction (HTL) is a technology that could offer utilities a biosolids management strategy that both enhances resource recovery by generating liquid fuels and has the potential to destroy PFAS. However, one by-product of the process, the HTL aqueous phase (HTL-AQP), currently requires costly pre-treatment as it can inhibit key wastewater biological processes. This project will explore whether HTL-AQP can be co-digested onsite in anaerobic digesters to overcome these inhibitory effects through controlled dosing and operational modifications. Aqueous from the world’s first demonstration-scale continuous-flow HTL system will be applied to pilot digesters to determine optimal operating conditions for digester performance while enabling resource recovery and PFAS destruction. If successful, this approach could eliminate the need for pre-treatment, which would realize considerable cost and energy savings.