A Review of Upscaling Hydrothermal Carbonization

Abstract

Hydrothermal carbonization (HTC) has recently emerged as a promising technology for converting diverse forms of waste with a high moisture content into value-added products such as biofuel, biochar, and activated carbon. With an increasing demand for sustainable and carbon-neutral energy sources, HTC has attracted considerable attention in the literature. However, a successful transition from laboratory-scale to large-scale industrial applications entails notable challenges. This review critically assesses the upscaling of hydrothermal carbonization processes, emphasizing the challenges, innovations, and environmental implications associated with this transition. The challenges inherent in upscaling HTC are comprehensively discussed, including aspects such as reactor design, process optimization, and the current treatment technology for process water. This review presents recent innovations and technological advancements that address these challenges and explores integrated solutions to enhancing hydrothermal carbonization’s scalability. Additionally, this review highlights key companies that have developed and implemented HTC plants for commercial purposes. By overcoming the obstacles and achieving advancements in the upscaling of hydrothermal carbonization, this review contributes to the ongoing efforts to realize the full potential of HTC as a sustainable and scalable biomass conversion technology and proposes future directions.