Assessment and Classification of Liquids Wastes Quality from a Food Processing Factory in the Korhogo Region Using a Combination of Water Quality and Pollution Indices
Kizito Katel Kahou Toe-Bi *
Department of Geosciences, Training Unit and Research of Biological Sciences, University Peleforo GON COULIBALY-Korhogo, P.O. Box 1328 Korhogo, Cote d'Ivoire.
Kouadio Kouassi Saint-Pierre
Department of Geosciences, Training Unit and Research of Biological Sciences, University Peleforo GON COULIBALY-Korhogo, P.O. Box 1328 Korhogo, Cote d'Ivoire.
Coulibaly Nango Ibrahim
Department of Geosciences, Training Unit and Research of Biological Sciences, University Peleforo GON COULIBALY-Korhogo, P.O. Box 1328 Korhogo, Cote d'Ivoire.
Gnamba Franck
Department of Geosciences, Training Unit and Research of Biological Sciences, University Peleforo GON COULIBALY-Korhogo, P.O. Box 1328 Korhogo, Cote d'Ivoire.
Brahima Seyhi
Department of Geosciences, Training Unit and Research of Biological Sciences, University Peleforo GON COULIBALY-Korhogo, P.O. Box 1328 Korhogo, Cote d'Ivoire.
Guede Koré Elise
Department of Mines and Reservoirs Engineering, Faculty of Geological and Mining Sciences, University of Man, P.O. Box 989, Man, Côte d’Ivoire.
Zeli Bruno Dgibehi
Laboratory of Geosciences of Sedimentary Environments and Energies, Training Unit and Research of Earth Sciences and Mineral Resources. University Felix Houphouet-Boigny of Abidjan-Cocody, 22 P.O. Box 582 Abidjan 22, Cote d'Ivoire.
*Author to whom correspondence should be addressed.
Abstract
Background: Liquid wastes from the food-processing factory are a major source of environmental pollution. There is a need to investigate the compliance of wastewater discharged from food-processing factories with regulatory standards.
Aim: To assess the physicochemical quality and pollution status of liquid effluents from a food-processing factory in Korhogo that operates without a wastewater treatment plant.
Study design: A total of 06 liquid-waste samples were collected from a food-processing factory in Korhogo.
Methodology: The samples were analysed in the laboratory in accordance with the standards in force at the Sub-Directorate for the Inspection of Classified Installations (SDIIC). Parameters assessed included temperature (T), turbidity (Tur), pH, biochemical oxygen demand (BOD₅), chemical oxygen demand (COD), total suspended solids (TSS), electrical conductivity (EC), nitrates (NO₃⁻), nitrite (NO₂⁻), phosphates (PO₄³⁻), total phosphorus (TP), ammonium (NH₄⁺), and total nitrogen (TN).
Results: The parameters were measured. The mean values of TSS, T, Tur, TP, TN, and pH in the effluents were 77.8 mg/l, 27.21°, 93.73 NTU, 37.99 mg/l, 36.966 mg/l, and 7.21, respectively. The reported average values for dissolved oxygen (DO), biological oxygen demand (BOD₅), and chemical oxygen demand (COD) were 2850 mg/l and 4750.16 mg/L, respectively. The average electrical conductivity (EC) was 7987.5 μS/cm, and the concentrations of anions and cations, including NO₃⁻, NO₂⁻, and NH₄⁺, were 1.63, 0.12, and 39.17 mg/L, respectively. Therefore, these results indicated elevated pollution levels, particularly for organic matter, ammonium, phosphorus, and suspended solids. BOD₅ and COD concentrations exceeded national discharge limits. The effluents showed high biodegradability, as reflected by the COD/BOD₅ ratio (0.6). The Comprehensive Pollution Index (CPI) ranged from 1.472 to 6.940, with 83.3% of effluents classified as heavily polluted. The Nemerow index identified all stations as seriously polluted. The Wastewater Quality Index (WWQI) ranged from 36.535 to 198.922, with 66.7% of effluents rated as very bad (Grade E).
Conclusion: These results underscore the need for effective wastewater treatment before discharge into receiving waters.
Keywords: Effluents, physicochemical parameters, water quality index, polluted index, biodegradability