Physicochemical characterization of leachates produced in the Rabat-Salé-Kénitra Region landfill technical center and monitoring of their treatment by aeration and reverse osmosis

Abstract

The aim of this work is to study the physicochemical characterization and monitoring of the treatment of leachate generated by the landfilling of household and similar waste in the landfill of Rabat-Salé-Kénitra Region. The analysis of the results showed a high concentration of easily biodegradable organic matter. The pollutant load is of the order of 3,850 mg/L of the chemical oxygen demand (COD), 1.260 mg/L of the biochemical oxygen demand (BOD5), and shows an average content of nitrates (NO3-=56.6 mg/L). This mineral pollution is caused by a high electrical conductivity, which reaches an average value of 15.9 mS/cm, and a low concentration of heavy metals in the raw leachate such as lead (Pb = 1.591 mg/L), copper (Cu = 1.017 mg/L), and cadmium (Cd = 0.109 mg/L). The biological treatment allows for the successive biodegradation of 40% of the BOD5, and 33% of the COD. Moreover, the reverse osmosis filtration in organic membranes achieves a reduction of 98% for BOD5, 97% for COD, 85% for lead, and 67% for copper. In this study, biological and reverse osmosis treatments represented an effective treatment for the organic and metallic leachate pollutants of this landfill.