Characterization and Management of Sewage Sludge in Abomey Calavi: Pathways to Sustainable Treatment Solutions

Authors

  • Nikita Topanou

    Kaba Laboratory of Chemical Research and Application (LaKReCA), Department of Chemistry, Faculty of Science and Technology of Natitingou, University of Abomey, Natitingou, Bénin
  • Blaise Agbatchi

    Kaba Laboratory of Chemical Research and Application (LaKReCA), Department of Chemistry, Faculty of Science and Technology of Natitingou, University of Abomey, Natitingou, Bénin
  • Gouvidé Jean Gbaguidi

    Kaba Laboratory of Chemical Research and Application (LaKReCA), Department of Chemistry, Faculty of Science and Technology of Natitingou, University of Abomey, Natitingou, Bénin
  • Fidèle Paul Tchobo

    Laboratory of Study and Research in Applied Chemistry, Polytechnic School of Abomey-Calavi, University of Abomey-Calavi (LERCA/EPAC/UAC), Cotonou, Bénin
  • Jacques Fatombi

    Kaba Laboratory of Chemical Research and Application (LaKReCA), Department of Chemistry, Faculty of Science and Technology of Natitingou, University of Abomey, Natitingou, Bénin

DOI:

https://doi.org/10.30564/jees.v7i6.9296
Received: 31 March 2025 | Revised: 23 April 2025 | Accepted: 29 April 2025 | Published Online: 28 May 2025

Abstract

In the Republic of Benin, as in many other West African countries, urban areas have experienced rapid population growth in recent years. This situation has led to an increasing demand for sanitation facilities, necessitating regular emptying of these systems. In a bid to reduce health risks and protect the surrounding natural environment, the management of the by-products from these systems has become a significant concern for decision-makers at various levels. This study aims to characterize fecal sludge at the Abomey-Calavi treatment station and suggest a mixed biological treatment approach. Fifteen sewage sludge samples were collected in 1,500 ml plastic bottles from Adjagbo's Sewage Treatment Station, operated by SGDS-SA, a Waste Management and Sanitation company. Physico-chemical parameters were determined using spectrophotometric analysis. Colonies were enumerated using membrane filtration and inoculation. Correlation analysis was performed on sewage sludge samples. The main results indicate an alkaline character (pH > 7) and a high organic pollutant load in the fecal sludge, with average concentrations of Chemical Oxygen Demand (COD) and Biochemical Oxygen Demand over 5 days (BOD₅) at 18,730 mg O₂.L⁻¹ and 6,612 mg O₂.L⁻¹, respectively. The COD/BOD₅ ratio of 2.83 suggests that the material is partially biodegradable. Furthermore, the nutrients exhibited high concentrations of nitrates, with an average value of 4,786 mg.L⁻¹, while nitrites, ammoniacal nitrogen, and orthophosphates had average concentrations of 22.48 mg.L⁻¹, 119.74 mg.L⁻¹, and 239.0 mg.L⁻¹, respectively. This study characterized fecal sludge at the Abomey-Calavi treatment station and suggests a mixed biological treatment approach.

Keywords:

Characterization; Fecal Sludge; Treatment; Benin

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How to Cite

Topanou, N., Agbatchi, B., Gouvidé Jean Gbaguidi, Tchobo, F. P., & Fatombi, J. (2025). Characterization and Management of Sewage Sludge in Abomey Calavi: Pathways to Sustainable Treatment Solutions. Journal of Environmental & Earth Sciences, 7(6), 63–72. https://doi.org/10.30564/jees.v7i6.9296

Issue

Vol. 7 , Iss. 6 (June 2025): In Progress

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Article

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Copyright © 2025 Nikita Topanou, Blaise Agbatchi, Gouvidé Jean Gbaguidi, Fidèle Paul Tchobo, Jacques Fatombi

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This is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.

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