Assessment of Biogas Production from Food Waste and Solid Wastes at Kaduna Polytechnic Campuses, Nigeria

Higher educational institutions in Nigeria face dual challenges of escalating municipal solid waste (MSW) generation and chronic energy deficits. The organic fraction of MSW (OFMSW), predominantly food waste, is typically disposed of via open dumping, releasing potent greenhouse gases. This study assessed the bioenergy potential of food and organic wastes generated across the four campuses of Kaduna Polytechnic, Kaduna, Nigeria. A 60-day stratified waste audit was conducted across students’ hostels, staff quarters, and cafeterias to determine the quantity and composition of solid wastes generated. Proximate analysis was carried out to determine the moisture and volatile solid content, while stoichiometric (Buswell) and empirical (IPCC) models were used to project biogas yields. The campuses generate 8,500 kg of solid waste daily, with food and organic wastes constituting 52.9% (1,343.00 kg/d). Proximate analysis revealed high moisture (64.18%) and volatile solids (84.50% on a dry basis), confirming the substrate's suitability for anaerobic digestion over thermal incineration. Using the IPCC biological treatment model, the annual recoverable methane potential is 764.4 m³ daily, which is capable of sustaining a 110.9 kW co-generation plant to produce 971,083kWh of electricity annually. These will ofsets an estimated 276,759 liter of diesel, saving approximately ₦512.004 million per year. Implementing a mesophilic anaerobic digestion system at Kaduna Polytechnic provides a viable circular economy framework, addressing waste disposal constraints while significantly offsetting institutional energy costs and diesel dependency.