Multi-response optimization of coagulation–flocculation process for stabilized landfill leachate treatment using a coagulant based on an industrial effluent
Abdelkader Anouzla, Malika Kastali, Karima Azoulay, Imane Bencheikh, Ghizlane Fattah, Jamal Mabrouki, Chirâa Elidrissi Elhassani, Boubker Ouadil, Khadija El-Moustaqim, Chaymae Bakkouche, Ali Moussadik, Latifa Mouhir, Khalid Digua, Salah Souabi, Redouane Khaoulaf, Souad El Hajjaji, H. Loukili, Nabil Saffaj, Mourade Azrour, Younes Abrouki
Abstract
ABSTRACT The aim of this study is to assess the performance of an industrial effluent steel industrial waste-water (SIWW) highly loaded with ferric salts from Maghreb Steel Company as coagulant for stabilized landfill leachate treatment. Response surface methodology and central composite design were applied to optimize the coagulation–flocculation process and to model the relationships between independent variables (coagulant dose and effluent pH) and responses (chemical oxygen demand (COD) and turbidity removal, and sludge production). Quadratic polynomial models developed for these responses indicated that the optimum conditions were 8 mL/L of SIWW at pH 2.75. These results showed good agreement between experimental and model predictions. 55.43% and 87.55% of COD and turbidity removal, respectively and with 19 mL/L of sludge production from treatment of this leachate by coagulation–flocculation using a SIWW-based coagulant were demonstrated. Accordingly, it is concluded that SIWW can be used as an effective and alternative coagulant for the pre-treatment of stabilized landfill leachate by a coagulation–flocculation process.