Dr. Valdes-Morales, Hector

This article presents a combination of coagulation–flocculation and powder activated carbon (PAC) adsorption as a treatment process for landfill leachate. Leachates were collected from a municipal solid waste landfill in Mediouna site, Casablanca city. Ferric chloride (FeCl3) is used here as a coagulant to study the optimum conditions for the removal of chemical oxygen demand (COD), colour, total suspended solids (TSS) and turbidity in jar tests. This coagulant showed the highest removal efficiency in terms of COD (62.5%), turbidity (92.5%), colour (80%) and least sludge volume generation (30% v/v) for an optimum coagulant dose of 12 g Fe3+ L–1. Combining coagulation with adsorption process onto PAC enhances the removal of COD, turbidity and colour reduction by a 77%, a 99% and a 99.7%, respectively. These results show that coagulation-adsorption could be used as a promising hybrid process for the treatment of landfill leachates.

This study aims: (a) to characterize the raw leachate generated in the landfill of Fez city, and (b) to evaluate the feasibility to apply an aerobic treatment followed by a Fenton oxidation process. The aerobic treatment was conducted in a suspended grow bioreactor during 60 days. The bioreactor was monitored every 3 days, following the variation of pH, chemical oxygen demand (COD), biochemical oxygen demand (BOD5), turbidity, conductivity, color number (CN), total suspended solids (TSS), nitrates (NO3−-N), nitrites (NO2−-N), and the absorbance values of the UV–vis spectrum. Results showed an elimination of41%, 31%, 50%, 52%, and 37%, on COD, BOD5, color number (CN), NO2−-N and NO3−-N, respectively. Thereafter, a Fenton oxidation process was successfully applied to the biological pre-treated leachate, improving the removal of COD, BOD5 and color to 73%, 99.5% and 94%, respectively.