Conference on Environmental Science and Technology

Hydrothermal carbonization (HTC) is an effective treatment method for sewage sludge, enabling the recovery of valuable metals such as zinc. This study investigates the effect of HTC on zinc partitioning between the solid and liquid phases at two temperatures (180°C and 200°C) and two reaction times (1 and 2 hours). The results indicate that increasing the temperature and prolonging the reaction time enhance zinc dissolution in the liquid phase, although a significant portion of zinc remains in the solid phase. Notably, the solid concentration is higher at 200°C compared to 180°C, suggesting that higher temperatures facilitate greater zinc retention in the solid matrix. ANOVA results confirmed that both temperature and time significantly influence zinc partitioning, with p-values below 0.0500 for main effects and their interaction. These findings highlight the potential of HTC to optimize zinc recovery from sewage sludge while reducing waste volume, contributing to more sustainable sludge management practices.