Optimisation of Torrefaction and Pelletisation Conditions for Durian Seed Biom

Abstract

Torrefaction of biomass is an effective thermochemical pre-treatment technology that improves biomass characteristics for solid fuel  (bio-coal) generation. The abundance of durian seeds in Malaysia led to their selection due to their high energy potential. A comparison  was made between the effects of torrefaction temperatures (200°C, 250°C, and 300°C) and residence periods (30, 45, and 60 min at 250°C)  on mass, energy yield, and calorific value. Torrefaction was carried out in a Protherm tube furnace under inert conditions, with a heating  rate of 10°C/min and a nitrogen flow of 0.2 L/min. The results reveal that 250°C for 30 min produces the best calorific value (22.529 MJ/kg)  while also maintaining high mass (23.2 wt.%) and energy yield (31.34%). Proximate analysis, surface chemistry, and thermogravimetric  analysis were utilised to investigate the properties of raw and optimised biomass. Torrefaction decreased moisture and volatile matter  while raising fixed carbon and ash levels. The optimum sample had 3.24 wt.% moisture, 62.93 wt.% volatile matter, 17.79 wt.% fixed  carbon, and 16.04 wt.%. The impact of pelletisation was also investigated, with various moisture contents (5 wt.%, 10 wt.%, and 15 wt.%)  impacting the process. At 5 wt.% moisture, the maximum durability (98.79%) and calorific value (22.956 MJ/kg) were obtained. Overall,  the study validates the effectiveness of durian seed biomass as a feasible renewable energy source.