Application of principal component analysis (PCA) to the study of the influence of the thermochemical treatment process of tropical wood sawdust on the calorific, mechanical, physicochemical and combustion properties of the resulting fuel briquettes

Abstract

Despite its potential for environmentally friendly energy production, lignocellulosic biomass has less advantageous physicochemical properties that limit its optimal industrial use. This study used principal component analysis (PCA) to evaluate the effects of two thermochemical processing methods (torrefaction and carbonization) on the calorific, physicochemical, mechanical and combustion properties of the resulting biofuels. Various types of tropical sawdust (Dabema, Dibetou, Fraké, Samba and Iroko) are subjected to these treatments, then densified and characterized for energy applications. Specific fuel consumption varies from Samba torrefied (Sam t: 0.69 kg/L) to Samba carbonized (Sam c: 1.48 kg/L). Higher heating values range from Samba torrefied (Sam t: 23983 kJ/kg) to Iroko torrefied (Iro t: 27,442 kJ/kg). Burning speed varies from Samba carbonized (Sam c: 3.07 g/min) to Iroko torrefied (Iro t: 4 g/min). The impact resistance index ranges from 187.5 to 500% for Dibetou torrefied (Dib t) and Samba carbonized (Sam c), respectively. Densities are between Samba carbonized (Sam c: 297.83 kg/m3) and Dibetou carbonized (Dib c: 393.69 kg/m3). The results indicate that these techniques are promising approaches for improving biomass properties. In sum, the PCA reveals that the effect of treatment type on fuel characteristics also depends on the properties of the initial biomass.