[01] Helen Olayinka Ogunsuyi, Department of Chemistry, School of Sciences, Federal University of Technology, Akure, Nigeria. [02] Waliyu Adedeji Oyebode, Department of Chemistry, School of Sciences, Federal University of Technology, Akure, Nigeria.

Nigeria has a vast amount of agriculture and forest residues that are grossly underutilized. The potentials of these biomasses considered as wastes can be tapped for energy generation. Therefore, the present study investigated the viability of wood dust biomass (Astonia congenisis) as feedstock for solid fuel production using a thermo-chemical conversion process such as Torrefaction process. The process was performed with an improvised torrefier. The effect of the torrefaction process on the fuel properties of the biomass was evaluated by performing the Fibre analysis (cellulose, lignin, hemicellulose), Proximate analysis (moisture content, volatile matters content, ash content, fixed carbon), Ultimate analysis (nitrogen content, carbon content, hydrogen, oxygen and sulphur content) and Energy value before (untorrefied) and after (torrefied) the torrefaction process. From the result, the energy value of 19.58 MJ/kg recorded for the untorrefied sample remarkably increased to 27.28 MJ/kg upon torrefaction at 200°C process temperature. The lignin content of the biomass increased from 30% to 64% after torrefaction. A slight increase from 39% to 40% was observed in the cellulose content of the biomass upon the thermo-chemical process. However, hemicellulose, extractives and holocellulose which were 28%, 10.50% and 67% respectively in the untorrefied sample decreased to 24%, 8.50% and 64% respectively upon torrefaction. The moisture content in the untorrefied biomass decreased from 22.50% to 17.50% after the torrefaction process. This observation was also noticed in the volatile matter composition of the biomass. Conversely, the ash content of the sample was discovered to be 2.00% in it untorrefied form and increased remarkably upon torrefaction to 4.00%. Furthermore, 17.50% fixed carbon was detected in the untorrefied (raw) biomass sample and was noticeably increased to 40.50% after torrefaction. These observations implied that torrefaction method is an effective thermo-chemical conversion process for solid fuel production from wood biomass due to its enhancing fuel properties potentials.

Biomass, Torrefaction, Bio-coal, Fossil-sourced Fuel, Wood Dust, Alstonia congenisis, Sustainable Energy

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