Polishing of treated textile effluent using combined electrochemical oxidation and ozonation technique

Textile effluents are known to be complex matrices, requiring a combination of treatment techniques to achieve conditions that allow effluent to be discarded into environment. The electrocoagulation technique manages to remove most of the pollutants present in textile effluents, but generally does not achieve complete removal. This work studied the efficiency of combined electrochemical oxi-dation and ozonation techniques in the post-treatment of a real textile effluent after electrocoagu-lation and decantation processes. The experiments were carried out in batch mode using Ti/RuO2 electrodes (2 plates) and an ozone generator (0.875 g center dot h-1 center dot L-1). Three current densities were studied, 33.3, 66.6, and 133.3 A center dot m-2. The turbidity, color, dissolved organic carbon, and pH were analyzed to evaluate the treatment process. The results showed higher efficiency for removing color and dis-solved organic carbon with increasing current density. Applying the ozonation process alone had the lowest color and dissolved organic carbon removal efficiencies. The best experiment was with the current density of 66.6 A center dot m-2 integrated with O3 promoted removal percentages of 91.77%, 33.02%, and 91.09% for turbidity, dissolved organic carbon, and color, respectively.