Influence of torrefaction pretreatment on corncobs: A study on fundamental characteristics, thermal behavior, and kinetic

The effects of torrefaction pretreatment on corncobs properties and its pyrolysis kinetic parameters were investigated in this study. Proximate and ultimate analyses indicated that torrefaction increased the H/C-eff ratio and higher heating value of corncobs, and reduced its oxygen content. Although the mass yield was also reduced, the corresponding energy yield was relatively higher. The crystallinity index of biomass showed a first upward and then downward trend with the torrefaction temperature. Kinetic parameters obtained from three models indicated that both the activation energy and the pre-exponential factor increased with the elevated torrefaction temperature and its better to calculate the activation energy by the OFW method and to use the KAS and DAEM methods to calculate the pre-exponential factor. In addition, it was found that the optimum pretreatment temperature of corncobs was 240 degrees C.