Abstract EN:

Torrefaction is a thermal degradation process carried in a temperature range between 250°C and 280°C under an inert atmosphere. This could be qualified as a mild pyrolysis process. The main goal of the torrefaction process is to dry the incoming biomass, to lower the energetic cost of its grinding and to make stable the final product of the operation. Hence, this product might became an energy carrier, suitable for both direct applications (heating) or indirect applications (gasification and subsequent use of the produced gas for chemistry or fuels). The potential industrial development of the process firstly requires that the knowledge associated with this operation be increased. For this reason, the influences of operating conditions on the product distribution and the reaction pathway undergone by biomass during its degradation have been studied in this work. This study, which is of the experimental type, has been completed by a numerical one. Indeed, a mathematical model (representative of a countercurrent reactor) has been developed and set up in this work. This model, which is based on a one dimensional approach, allows for a better understanding of the phenomena occurring within such a reactor. It has also been used in order to design a two kilogram an hour experimental facility that was built in the frame of this work and in the frame of the consortium PREBIOM.