Potassium impregnation assessment of mild biomass pyrolysis by catalytic torrefaction severity factor

Source Agritrop Cirad (https://agritrop.cirad.fr/612857/) ; International audience ; The increasing challenge for newenergy sources has called for a green-energy breakthrough. Concerning biomass conversion technologies, the thermochemical route appears as a feasible pathway carrying the potential for substantial innovations and process optimization. Torrefaction is a key thermal treatment for solid fuel upgrading. Different indicators of torrefaction process performance have been defined to characterize the torrefaction severity degree. Nevertheless, no study presented a calculated index that correlates catalytic effects with the operating parameters (treatment temperature and time), biomass nature and feedstock sensitivity at the same time. Previous works indicated that biomass potassium impregnation could increase thermal degradation processes by catalytically influencing the component's conversion mechanisms. Therefore, this study examines the potassium impregnation catalytic effect by applying the torrefaction catalytic effect index (TCEI) and the new catalytic torrefaction severity factor (CTSF). Previous work data of thermogravimetric analysis (TGA) of Eucalyptus clone impregnated with three different potassium carbonate concentrations (K2CO3) was applied for the catalytic severity index assessment.The calculated indexes showed a good correlation with the weight loss, providing two new indexes for the treatment assessment under catalytic effect conditions.