Torrefaction assessment and kinetics of deoiled Karanja seed cake

This study demonstrated the efficiency of torrefaction pro-cess in upgrading the efficiency of lignocellulosic bioresource,deoiled Karanja seed cake. Torrefaction was carried out at dif-ferent temperatures within the residence time ranging from 10to 90 min. Elemental analysis clearly shows that there is a sig-nificant reduction in H/C and O/C ratio. The mass loss wasfound to be higher than that of carbon loss which eventuallyleads to the energy densification. For an average weight loss of30-35%, the HHV was found in the range of 19.5-21.5 MJ/kgand the total energy that remained in the fuel was around 80-85%. Torrefaction kinetics of karanja deoiled cake was fol-lowed to study the thermochemical decomposition and globalone step reaction mechanism gave the best representation ofthe data. The kinetic model proposed provides the recommen-dations for industrial torrefaction process conditions, remark-ably the operating temperature and residence time. Theactivation energies and pre-exponential factors for thermaldegradation, charification, and volatilization were calculatedto be 10.55, 30.39, and 3.16 kJ/mol and 0.341, 8.728, and0.446 min21, respectively.