Hydrothermal Carbonization of Pruned Persimmon Tree Branches: Optimization of Process Conditions for Enhanced Energy...

Pruned branches from persimmon trees are a largely untapped agricultural waste resource. This study explores the conversion of these branches into an enhanced fuel source through hydrothermal carbonization. The branches were subjected to hydrothermal treatment under various conditions to identify the optimal parameters. Higher temperatures and longer treatment durations increased the carbon content to 69.2% and reduced the oxygen content to 20.4%. A Van Krevelen diagram showed that dehydration was the primary reaction, with decarboxylation occurring at 250 °C. The energy value increased from 18.2 MJ/kg for raw branches to 28.5 MJ/kg under the optimal conditions, indicating a 57% improvement. These findings demonstrate that hydrothermal carbonization effectively utilizes persimmon pruning waste, offering a sustainable method for converting biomass into energy and aiding agricultural waste management.