Contribution to the Physico-Chemical Characterization of the Wastewater of Four Industrial Units of Preserve and Semi Fish Preserve of the City of Anza (North of Agadir)

Abstract

The main objective of this study is to characterize the industrial wastewater of the city of Anza located north of Agadir in southwestern Morocco in order to recommend an adequate treatment allowing their reuse, thus reducing the nuisances that undergo the receiving environment (Anza Beach). This study concerns four industrial canned and semi-preserved fish plants that directly discharge their wastewater into the Anza beach. The physicochemical characterization of raw wastewater throughout 2017 revealed that these liquid discharges are heavily loaded with organic matter in terms of COD (Avg = 10557 mg O₂ / L) and BOD₅ (Avg = 4877 mg O₂ / L). ), in TSS (Avg = 3537 mg / L) in mineral matter expressed in terms of chlorides (Avg = 25749 mg / L), and in electrical conductivity (Avg = 68957 μs / cm) with a mean pH close to neutrality. The average levels of total nitrogen and total phosphorus are respectively of the order of 631 mg / L and 84 mg / L. Although these wastewaters have a high organic load (ratio BOD₅ / COD = 0.46 and TSS / BOD₅ = 0.72), they have a satisfactory biodegradability. Examination of the COD / BOD₅ ratio of about 2.16 clearly underlines the biodegradability of the industrial wastewater studied. Biological treatment seems quite suitable.