Electroflotation treatment of stabilized landfill leachate using titanium-based electrode

Abstract

Landfill leachate is one of the most obstinate wastewaters to be treated due to its toxic organic and inorganic pollutants. The landfill leachate must be treated prior to discharge into a watercourse in order to preserve human health and ecosystem. Pre-characterization of raw landfill leachate was done to identify the concentration of certain pollutants, in which the effluent concentration of chemical oxygen demand, ammoniacal nitrogen, and color was 1990 mg/L, 300 mg/L, and 1946 Pt–Co, respectively. The present study was conducted to treat raw landfill leachate using the electroflotation system with a designed titanium and coated titanium DSA electrodes. The experiments were conducted following the central composite design of experiments, and the design was analyzed using response surface methodology (RSM). The influence of current density, initial pH, and contact time was evaluated on the removal of COD, NH3–N, and color by ANOVA. It was found that current density and pH were the most effective parameters on COD and NH3–N removal; nevertheless, the color obtained the highest removal was up to 80%. The optimal experimental conditions were determined to be current density of 28 (A/m2), initial pH 6.0, and processing time of 30 min. Under these experimental conditions, the maximum removal of COD, color, and NH3–H was 75%, 63%, and 83%, respectively. The findings of the present study reveal that the electroflotation technique could be utilized to treat landfill leachate as an effective pre-treatment process.