Evaluation of Composting as a Solid Waste Management Option for University Campuses in Nigeria: Case Study of Ahmadu Bello University, Zaria

This study evaluates the feasibility and effectiveness of composting as a solid waste management strategy at Ahmadu Bello University in Zaria, Kaduna State, North West Nigeria. University campuses in Nigeria generate large volumes of organic waste from student cafeterias, staff residences, and landscaping activities, and open dumping of this material creates aesthetic, pest, and odour problems. A pilot composting programme was established at two campus locations, employing open windrow composting with periodic turning of organic waste collected from the main cafeteria, student hostels, and campus gardens. Windrow temperatures, moisture content, carbon-to-nitrogen ratio, and biological oxygen demand of the maturing compost were monitored over a twelve-week decomposition cycle. Product quality was assessed against Federal Ministry of Agriculture compost quality standards, including pH, heavy metal concentrations, and phytotoxicity bioassay. Results show that windrow temperatures reached thermophilic ranges above 55 degrees Celsius between weeks two and five, indicating active microbial decomposition and effective pathogen reduction. Final compost achieves a carbon-to-nitrogen ratio of 14, a near-neutral pH, and heavy metal concentrations within acceptable limits. Phytotoxicity testing using maize seedlings shows no growth inhibition in the finished compost. Waste diverted from open dumping averages 620 kilograms per week across both sites. Economic analysis indicates that compost sale to campus agricultural stations and surrounding farms could cover operational costs. The study recommends a campus-wide composting programme with mandatory source segregation of organic waste. Keywords: composting, organic waste, solid waste management, university campus, Ahmadu Bello University.