Evaluation of the Kossodo Wastewater Treatment Plant Efficiency in Burkina Faso, West Africa
- Australian Journal of Basic and Applied Sciences : 2-11
Résumé
Background: In 2004, Burkina Faso established the Kossodo wastewater treatment facility, utilizing a lagoon system. The plant was designed as both a cost-effective and efficient solution, with the additional benefit of enabling the reuse of treated wastewater. Objective: This study aims to examine the current state of its operation, assess the wastewater purification performance, and suggest ways of improving the quality of the effluent with a view to its possible reuse. To achieve this objective, bi-weekly samples were taken over six weeks. Composite sampling was carried out for the raw water, while spot sampling was carried out for the effluent from the maturation basin. Results: The pollution indicators examined consisted of Chemical Oxygen Demand (COD), filtered COD, 5-day Biological Oxygen Demand (BOD5), Suspended Solids (SS), ammonia nitrogen, nitrates, total phosphorus, and ortho-phosphates. As regards microbial contamination, fecal coliforms and specifically Escherichia Coli were tested. The removal rates for COD and BOD5 were recorded at 20.24% and 82%, respectively. Despite this, the average concentration of TSS in the treated water remained relatively high at 266.72 mg/l, surpassing Burkina Faso's standards for the discharge of treated wastewater into surface water, which are set at 150 mg/l for unrestricted reuse. In addition, pathogen elimination proved to be very poor, or even non-existent, with yields that were sometimes negative. The inadequate purification performance of fecal contamination indicators is reflected in residual concentrations above 2000 CFU/100 ml, well above the standard recommended for discharge into the natural environment in Burkina Faso. Conclusion: It is therefore crucial to improve the operation of this plant to guarantee a better quality of treated effluent, in compliance with current standards.
Mots-clés
Effluents, Discharge standards, Microbiological quality, wastewater treatment plant, Kossodo, Ouagadougou, Burkina Faso