Determination of kinetic constants and thermal modeling of pyrolysis of palm oil mill solid wastes

Empty fruit bunches, fiber, and shell are the main solid residues produced during oil extraction process from oil palm (Elaeis guineensis Jacq.). These biomass were subject to thermogravimetric (TG) and differential scanning calorimetry (DSC) analyses to determine the kinetic parameters activation energy (E), frequency factor (A), and reaction order (n). The shapes of TG and DSC curves were used to identify the number of thermal degradation steps for these materials. Thermal degradation kinetic parameters were obtained for each of the steps identified. TG and DSC curves were used in a thermal model for predicting char production during the pyrolysis of shell in an indirectly heated continuous reactor. The model consisted in establishing a set of equations that allows predicting temperatures and residual mass in different parts of the reactor. Using the software Engineering Equation Solver (EES), the model was capable of calculating char yield with a 1.12% error compared to the measured values. The model was used to predict char production on fiber and EFB at different temperatures.