Potentials of sustainable electricity production from sawdust by small-scale wood transformation units: a case study in Cameroon

Wood processing produces large volumes of residues which, when not properly managed, pose an environmental problem in the vicinity and beyond. These residues mainly constituted of sawdust and wood shavings, possess important energy potentials that are largely underexploited in Cameroon. In this work, we investigate the possibility that sawdust generated by wood transformation units (WTU) in Cameroon can be used sustainably to render them self-sufficient in terms of electricity demands through the production of syngas in a gasification process. Both qualitative and quantitative methods are used in the research. Initially, a questionnaire was employed to quantify the sawdust produced in the town of Yaounde, Cameroon. A major WTU “LFM_Scierie” was selected to evaluate the feasibility of electricity generation from syngas produced by gasification of its wood waste. Proximate analysis of sawdust sampled from the LFM sawmill included moisture content 17.74 ± 0.27%, ash content 3.91 ± 1.54%, volatile matter 74.62 ± 1.47%, and fixed carbon 3.73%. The gross calorific value of the sawdust sample was estimated to be 20.08 MJ/kg. The total quantity of sawdust produced in the Yaounde municipalities is 290 tons/week which translates to an energy potential of 713 GJ/week. Theoretical calculations and modelling using a thermodynamics software, Cycle-Tempo, indicate that the amount of sawdust generated at the LFM sawmill of about 7 tons/week, can conveniently satisfy its electricity demands of approximately 3.3 MW/week. Small-scale WTUs in Yaounde can be rendered energy-autonomous by the generation of electricity from syngas produced via a gasification process of its waste.