VALORISATION OF CASSAVA PEEL WASTE THROUGH MICROBIAL FERMENTATION FOR PRODUCTION OF BIOETHANOL AND BIOGAS IN SOUTHWEST NIGERIA

Abstract

The increasing generation of cassava peel waste (CPW) in Southwest Nigeria poses significant
environmental challenges while representing an underutilised biomass resource for renewable
energy production. This study investigates the valorisation of CPW through microbial
fermentation for the dual production of bioethanol and biogas, integrating experimental
optimisation with techno-economic and environmental assessments. Cassava peel samples were
collected from major processing communities in Oyo, Ogun, and Ondo States and characterised
for biochemical composition. Indigenous microbial strains were isolated, identified, and applied
in batch fermentation and anaerobic digestion processes. Fermentation parameters were optimised
using Response Surface Methodology, while bioethanol and biogas yields were quantified using
gas chromatography and volumetric methods, respectively. Results show that CPW contains high
levels of fermentable carbohydrates and supports substantial bioethanol and methane yields, with
indigenous microbial strains outperforming commercial counterparts. Techno-economic analysis
indicated favourable economic viability with a short payback period, while life cycle assessment
revealed significant reductions in greenhouse gas emissions and waste volume compared to
conventional disposal. The study demonstrates that CPW valorisation offers a sustainable, circulareconomy pathway for renewable energy generation and waste management in cassava-producing
regions of Nigeria.