Experimental and numerical investigation on a solar-driven torrefaction reactor using woody waste (Ashe Juniper)

In this work, designs a novel solar-driven thermochemical conversion reactor to torrefy biomass waste (Ashe Juniper) for further pyrolysis applications. The effect of torrefaction temperature and residence time on the properties of biomass waste was investigated and results showed that torrefaction temperature dominates the properties of product compared to the effect of residence time. The highest energy yield (over 90%) was obtained at 210 ℃ while the highest energy densification (∼1.51) was achieved at 360 ℃. In addition, a two-step kinetic numerical model was used to analyze and predict the experimental process (kinetic rates) and results (C, H, and O contents) based on the experimental results. The analysis results showed that the predicted results are in good agreement with the practical results after torrefaction, indicating the feasibility of this numerical model for torrefaction and pyrolysis applications. The carbon footprint analysis showed that reduction effect of 1.3 ∼ 1.6 tCO₂/ton-AJ can be obtained by torrefaction of Ashe Juniper. Finally, the prospects for future industrial applications of solar-driven torrefaction reactors discussed as one of affordable and clean energy.