Authors : L.E. Ndulue, C.N. Anyanwu, V. Ogwo and C.C. Mbajiorgu
Abstract: Agricultural wastes are by-products of agricultural activities and take the form of crop residues (residual stalks, straw, leaves, roots, husks, shells etc.) and animal waste (animal faeces, droppings, etc.). In Nigeria, large quantities of these wastes are produced daily and are widely under-utilized. The traditional practice is to burn these residues or leave them to decompose. Agricultural wastes or residues are stock piles of energy that could be processed into liquid fuels or combusted/gasified to produce electricity and heat. This study reviews the energy potentials of common agricultural wastes like cassava peel, sugarcane bagasse, yam peel, plantain peel, wood sawdust and livestock droppings. Nigeria is currently the largest producer of cassava in the world with about 52.4*106 tons of cassava in 2011 and about 5.24-7.86*106 tons of cassava peels which have energy potential of about 85.83-128*109 MJ and 3.14-4.72*106 m3 of biogas. About 2.1*106 tons of corn cob is generated annually which can generate 3,922.45 MW of power, 1.062*09 m3 of biogas, 0.67*109 of methane (CH4) and 27.824*09 MJ of energy. About 4.74-6.42*106 tons of yam peel can generate about 77.79 -100*109J of energy. Plantain peel generated is about 0.95-0.96*106 tons and can generate 15.3-15.5*109 MJ of energy. About 2.09-2.5*103 kJ can be derived from 0.12-0.14*106 tons of sugarcane bagasse that is currently discarded. Also about 1.8 million tons of sawdust is generated annually and it has an estimated energy value of 31,433 MJ that is capable of generating 2.57*106 MWh that can provide electricity for about 347,297.3 homes/yr, assuming that each residential home consumes 7.4 MWh per year. Nigeria currently produces about 4.57*106 tons/day (chicken-broiler), 147.72*106(goat) tons/day, 84.2*106 (sheep) tons/day, 311.4*106 (cow) tons/day, 27.18*106 (pig) tons/day totaling 575.1*106 tons/day of animal wastes which is capable of generating 1.73*107 m3/day of biogas that can provide 1.94*104 MWh for about 262.2 homes/year for residential homes.
L.E. Ndulue, C.N. Anyanwu, V. Ogwo and C.C. Mbajiorgu, 2013. Agricultural Wastes as Potential Energy Resource in Nigeria: Current Status, Prospects and Constraints. Research Journal of Agronomy, 7: 1-12.