Characterization and energy analyses of municipal solid waste in Obafemi Awolowo University, Southwestern, Nigeria

Abstract

This study investigated the potential of generating electricity from municipal solid waste (MSW) generated in OAU. It also determined the quantity of municipal solid waste generated within OAU community and characterized the energy content of the combustible portion of the collected MSW. This was with a view to predicting theoretical quantity of electricity that can be generated from the MSW collected within OAU community.  Load-count-analysis was used for the MSW quantification while sampling method was used for the characterization of the collected samples. A total of ten samples of 10 kg each were collected from OAU dumpsite (Asunle) in September 2015 (wet season). The collected samples were sorted, weighed and separated into combustible and non-combustible fraction. The combustible portion was thoroughly mixed and shredded with milling machine to size of less than 3 mm for laboratory analysis. The calorific value of the samples was determined using bomb calorimeter following the standard method. The energy content of the MSW was analysed based on result of the quantification and the composition. Results of MSW quantification indicated that the total amount of waste generated on a daily basis was approximately 4.4 ton. Characterization showed that the waste was made up of approximately 34.8% paper, 18.1% textile, 9.4% electronics, 4.4% metal, 6.2% bio, 6.3% wood and 20.8% miscellaneous. Combustible fraction was 65.4% while the average moisture content was 19.04% on wet basis (w.b). The average calorific value obtained was 10.77 MJ/kg. The energy analysis indicated that, with minimum conversion efficiency (25%), 0.4MW of electricity could be generated. The study concluded that the MSW in OAU has capacity to generate electricity to the tune of 0.4MW on the basis of 4.5 tonne of waste collected per day with minimum conversion efficiency of 25%.