Quantification of biodegradable household solid waste for biogas production and the challenges of waste sorting in Abeokuta Metropolis, Nigeria

Household solid waste management is a major challenge in developing countries due to poor waste management practices and infrastructure. This study quantified the volume of biodegradable waste that was generated at the household level, which could be utilized for biogas production in Abeokuta city. Three residential areas were selected from each of the residential categories (low, middle, and high), and five houses picked randomly for household waste survey in each area. In each of the houses, colour-coded waste bins with instruction for waste sorting pasted on them were used for waste sorting. At an interval of 3 days, the wastes in the bins were collected, sorted into different categories, and weighed using a Griffin and George spring balance. Waste volume per area was computed by multiplying household waste volume and the number of houses estimated from high-resolution satellite images. The proportions of biodegradable waste in each of the low-, middle-, and high-income areas were 4.07 kg, 7.90 kg, and 9.68 kg per week, which constituted 71%, 67%, and 66% of the total household waste, respectively. The low-income areas had the highest electricity generating potential of 529 GWh, and Adatan had the highest biogas potential of 100 million m3/a and electricity of 241 GWh/a. A combined volume of 565 million m3 of biogas could be produced from the waste generated in the study area per year. Introduction of waste-to-energy scheme is capable of reducing pollution in the study area.