V1I7P6

Development of a Sustainable Wastewater Management Plan for the Oko-Oba Abattoirs, Lagos State, Nigeria

Taiwo Bakare-Abidola^1*, Christopher M. Adeniji² , Jelil  Olaoye³, Esther Chigbaziru  Nwojiji⁴, Adams Oladapo Adewale⁵, Audu Adeiza Abdulgafar⁶

Abstract

Abattoir wastewater discharge in Lagos State, Nigeria poses severe environmental and public health risks due to inadequate treatment systems, necessitating comprehensive sustainable management solutions. This study conducted systematic physicochemical and microbiological characterization of wastewater from Oko-Oba Agege and Ejigbo abattoirs through collection and analysis of twenty samples over five weeks, employing atomic absorption spectrophotometry for heavy metal analysis and standard methods for conventional parameters. Results revealed severe contamination with BOD₅ (2,420-2,850 mg/L) and COD (3,650-4,200 mg/L) exceeding regulatory limits by 48-57 fold, heavy metal concentrations surpassing WHO guidelines by factors of 5-78 (particularly lead and iron), and Metal Pollution Index values of 2.1-4.2 indicating heavy pollution status requiring immediate intervention. Laboratory-scale treatability studies demonstrated that an integrated anaerobic-aerobic biological treatment system with membrane separation achieves >95% pollutant removal efficiency while enabling substantial resource recovery including 2,850 MWh annual biogas energy, 145 tonnes struvite fertilizer, and 285,000 m³ reclaimed water, with economic viability showing 8.5-year payback period and $514,500 annual revenue potential. The proposed sustainable management framework provides a viable pathway for transforming waste streams into valuable resources while achieving environmental compliance and supporting Nigeria’s transition toward circular economy principles in industrial wastewater management.

Keywords: Wastewater characterization, physicochemical analysis, anaerobic digestion kinetics, membrane bioreactor, resource recovery, circular economy, heavy metal removal, biogas production