Wood Residues as Fuel in Pulp Paper Manufacturing Industries in Nigeria

ABSTRACT Frequent interruption in the supply of electricity from the National grid and occassional scarcity of fossil fuels (including diesel oil, the usual fuel for stand-by power units) are adversely affecting manufacturing industries in Nigeria. The remote location of pulp/paper industries is an added disadvantage in that electricity from the national grid are only available at great initial capital costs. Energy requirements per day, for the conversion of wood to paper at the mills at Oku-Iboku, Cross Rivers State; Iwopin, Ogun State and Jebba, Kwara State are estimated as being 10.784 TJ, 5.841 TJ. and 5.841 TJ. respectively. Mill residues (including combustible products in black liquor) that would be available during each working day in these mills have total heat energy contents of 1.02, 2.67 and 1.76 TJ respectively. Residues in the forests are less likely to be available for energy generation; these are estimated to have heat energy contents of 8.00, 5.39 and 3.15TJ respectively. Conversion efficiencies to useful energy may vary from over 50% for the generation and use of process steam to less than 20% for use in electricity generation, using steam engine power. Pulp and paper industries in Nigeria are likely to be constrained to look up more to these wastes for their energy requirements in future. The chances of this expectation are quantified and the implications are appraised.