Abstract
Hydrothermal carbonization (hereinafter, HTC) is an interesting thermochemical process through which wet biodegradable residues can be directly transformed into value added products. The main HTC products are the hydrochar, a solid carbonaceous material, and several chemicals dissolved within the liquid phase. In the last years, a vast research effort has been conducted on the study of the chemical reactions occurring during this process. In particular, the evolution of the chemical species during HTC has been the focus of many research activities. In order to understand this evolution, tests have commonly been performed using batch reactors, that have been cooled down at different process times to sample the process products for further analyses. However, the cooling down process can alter the real chemical and physical properties of the HTC products, and thus the analyses might produce not completely representative results. In order to avoid this and to allow a continuous sampling of the products during the process, a new reactor design has been developed by the Italian company HBI. With this new reactor, direct products sampling can be conducted. The reactor was tested with model compounds, such as wood and cellulose, and preliminary results have been described in this work.