Treatment Performance of Textile Wastewater Using Electrocoagulation (EC) Process under Combined Electrical Connection of Electrodes

The electrocoagulation (EC) process (using electrically coupled interconnections) was investigated for the treatment of textile wastewater. The impact of several operating parameters such as bipolar electrode element (Fe or Al), electrolysis time (RT), current intensity (I), pH, chemical support, inter-electrode distance (IED), and stirring speed (Mrpm) were examined. Additionally, the consumption of electrodes and electrical energy, sludge compaction, operating costs and a comparison with the traditional chemical coagulation method has been thoroughly investigated. The most suitable EC performance was achieved by using monopolar and bipolar aluminum-type plates. These plates were alternated within the electrode pack for 90 min. Preliminary results showed the following optimal operating conditions: I=0.6 A, pH=6, NaCl=0.1 kg/m3, IED=0.5 cm, and Mrpm=500. The implementation of these parameters on textile wastewater revealed a relatively high removal efficiency of COD (92.6%), TSS (96.4%), color (96.5%), BOD5 (88%), TDS (87%), turbidity (96%), phenols (over 99%), and phosphate (95%). The overall operating cost for the EC operation was 1.76US$/m3. This value was calculated based on the electrode and energy consumption, chemicals, and sludge disposal. The EC operation was found to be more efficient than the traditional chemical coagulation process.