Utilization of aromatic plants residual biomass after distillation mixed with wood in solid biofuels production

In this study, the potential utilization of industrial distillation residues of aromatic plants (helichrysum, crithmum and lavander) was investigated, through their incorporation into fir wood biomass feedstock for the production of solid biofuels in the form of fuel pellets, in an attempt to find alternative to wood raw materials and new avenues of such wastes management. The raw materials were crushed, processed, and pelletized in various proportions of fir wood, so that the ash content remained within the limits of the residential quality classes. The pellets were characterized in terms of their mechanical, physical, chemical and thermal properties. The results showed that all the produced pellets met the requirements of the standards in terms of calorific value, moisture, bulk density and dimensions. The addition of helichrysum enhanced pellets calorific value, while crithmum and lavender slightly deteriorated it. Pellets containing lavender and helichrysum in high contents and crithmum in low contents indicated significantly higher mechanical durability than pure fir wood pellets. Significant correlations among pellet-properties were revealed. The aromatic plant wastes, mixed with pure wood in appropriate ratios, could contribute to the production of high value-added products of solid biofuels, ensuring improved pellets performance and a sustainable waste management pathway.