Torrefaction of corncob and khat stem biomass to enhance the energy content of the solid biomass and parametric optimization

Agricultural biomass, as a renewable energy source, is critical in reducing the negative effects on the environment and the depletion of fossil fuels. Corncob and khat stem agricultural residues were investigated as a source of energy in the current study after their energy value was increased through torrefaction. The response surface methodology was used in the investigation of torrefaction parameter optimization. Torrefaction temperature and residence time were investigated as independent variables on energy yield. The energy yield obtained at optimum torrefaction conditions (300 °C, 30 min) was 98.5 % in corncob and 94.9 % in khat stem (300 °C, 45 min). Torrefaction bio-residues significantly affected all of the investigated attributes, according to the findings. Torrefied corncob and khat stem produced demonstrated good mass yield and energy yield characteristics, as well as a corresponding heating value. Torrefied biomasses are used as energy sources for industrial applications, according to the results of the torrefaction process.