Experimental investigation of heating values and chemical compositions of selected fuel woods as bio-fuel sources in developing countries

Abstract

Agro-waste disposal is a serious environmental problem in developing countries like Nigeria since there are insufficient waste management systems in place. However, it is possible to produce sustainable energy from these biomass wastes, which will lessen environmental damage. The heating value of biomass determines its energy content. The aimof this study was to determine experimentally the higher heating value (HHV) of five selected indigenous fuelwood sawdust and to assess the chemical composition of the pyrolysis yield products using a gas chromatography-mass spectrometry (GC–MS) analyzer. Results of the experimental analysis show that the HHVs of the selected fuel woods: Adansonia digitata (Ad), Terminalia ivorensis (Ti), Khaya ivorensis (Ki), Mansonia altissima (Ma), Okoubaka aubrevillei (Oa) are respectively, 21.02, 20.78, 20.75, 19.95, 19.80 and 20.46 MJ kg−1. According to ultimate analysis-based correlation equation, the HHVs were found to be 18.56, 18.48, 18.42, 18.39 and 18.36 MJ kg−1 for Ad, Ti, Ki, Ma and Oa, respectively. While the proximate analysis-based correlation equation gave HHVs of 18.08, 18.12, 18.25, 18.16 and 18.37 MJ kg−1 for Ad, Ti, Ki, Ma and Oa, respectively. The mean square error (MSE) was used to compare the deviation of the computed results from the experimental data. The statistical analysis indicates comparative agreement between the computed HHVs and the experimental data. The GC–MS analysis shows the presence of phenolic, ketone, fatty acid, ester, and alcohol compounds in the sawdust samples which is evidence that they have chemical and fuel compositions suitable for use as feedstocks in the pharmaceutical and dye industries as well as for the production of biodiesel for internal combustion engines. It can be inferred that the woody biomass residues can be useful sources of biofuels for developing nations' sustainable energy development if adequately processed with suitable technologies.