Conversion mechanism and gasification kinetics of biomass char during hydrothermal carbonization

摘要

In order to clarify the conversion mechanism and gasification performance of biomass char during the hydrothermal carbonization (HTC) process, and expand the application field of biomass hydrochar, the physicochemical characteristics and gasification performance of corn cob (CC) and CC hydrochar prod-ucts were systematically studied. The results show that with the increase of HTC temperature, the mass yield (MY) of CC hydrochar decreases, the high heating value (HHV) increases, and the physicochemical properties of CC are significantly improved. In addition, the gasification reaction time of hydrochar in-creases with the increase of HTC temperature. When the HTC temperature exceeds 280 degrees C, the tem-perature is no longer the main factor affecting the MY of the hydrochar. The volume model has a good fitting result on the gasification process of CC hydrochar. The apparent activation energy of the gasifi-cation reaction of the samples is calculated in the range of 380.99-610.82 kJ/mol. HTC can efficiently convert biomass into solid fuel with high energy density, which provides a reliable theoretical basis for expanding the application field of the biomass hydrochar. (C) 2021 Elsevier Ltd. All rights reserved.