Characteristics Study of Wood Wastes from Sawmills

Abstract

The availability of energy in wood wastes is evaluated in this work. Biomass from seven tropical wood species; Obeche (Triplochiton scleroxylon); Iroko (Melicia excelsa); Danta (Nesogordonia papaverifera); Mahogany (Khaya ivorensis); Omo (Cordia platythyrsa); Mansonia (Mansonia altissima) and Afara (Terminalia superba) retrieved from sawmills across Akure and its environment in South West Nigeria were pyrolysed in a fixed-bed batch thermal reactor. Laboratory experiments revealed that the wood wastes possess energy that can be converted for use in other forms such as fuels and chemicals. The volume of the three products of pyrolysis – char, pyro-oil and pyro-gas were evaluated for every kilogram of wood biomass pyrolysed. Wood off-cuts prepared into 50 x 20 x 20 mm were used, and it was found that wood has an average energy content of 21.7544 MJ/kg, made up of 8.52 MJ (39.15%) in the char, 8.76 MJ (40.26%) in the liquor, and 4.48 MJ (20.59%) in the pyro-gas; low ash content of 4.15% and electricity equivalent of 6.06 kWh, made up of 2.37 kWh (39.12%) in the char, 2.44 kWh (40.26%) in the liquor, and 1.25 kWh (20.62%) in the gas.