Hydrothermal liquefaction of wastewater as part of tailoring biocrude composition for a circular bioeconomy: A review
Timoth Mkilima
Abstract
Abstract Hydrothermal liquefaction (HTL) is emerging as a transformative technology in wastewater valorization, transitioning from a biofuel production focus to a platform for generating tailored high‐value products. This review explores the paradigm shift toward leveraging HTL to optimize biocrude composition for specific applications, fostering innovation in circular bioeconomy practices. Traditional wastewater treatment systems primarily aim at pollutant removal, often neglecting the significant resource recovery potential embedded within waste streams. Hydrothermal liquefaction disrupts this conventional approach by converting wet organic waste into biocrude, a versatile energy‐dense mixture. Despite its promise, the inherent heterogeneity of biocrude has long hindered its downstream refining and application. This review emphasizes advancements in controlling HTL reaction conditions, such as temperature, pressure and residence time, to selectively enhance the yield of targeted chemical families within biocrude, simplifying refining processes and opening avenues for high‐value applications. By integrating HTL with predictive modeling and fractionated biorefining techniques, the process scalability and product specificity are significantly improved, demonstrating its potential to redefine wastewater as a resource rather than a liability. This innovative approach underscores HTL’s critical role in driving the development of a circular bioeconomy, turning waste streams into tailored resources for energy, chemicals and material recovery.