Evaluation of Electrocoagulation and Activated Carbon Adsorption Techniques Used Separately or Coupled to Treat Wastewater from Industrial Dairy

Abstract

Abstract This present study focuses on the evaluation of the effectiveness and the feasibility of a combined treatment between the electrocoagulation (EC) and the adsorption on an activated carbon in grains (GAC) in a continuous mode. The peculiarity of this work is that the experiments are conducted with real wastewater from an industrial dairy. This combined treatment first required an optimization of the EC followed by an adsorption. For each of these techniques, different influential operating parameters such as the current density, the reaction time, the GAC dose, the initial turbidity of water … etc., have been studied. The Turbidity and the COD have been continuously analyzed, while the phosphorus, the BOD5, TSS, nitrogen and the grease have been punctually analyzed, and this happened before and after the water treatment. The EC adsorption coupling results have shown that the addition of an appropriate dose of GAC (2 gL−1) in a separate column, increases the effectiveness of treatment; more than 98 % of reduction for the COD, the BOD5, the turbidity and the greases. A mechanism explaining the phenomena which are involved in this combined treatment is proposed. On the basis of these results of efficiency, speed, low operational cost (~ 3 $m−3 of the treated water), and in comparison with the EC used alone, the EC coupling/the adsorption GAC, could be recommended as a treatment of separation for waters at a high load in organic pollutants.